Vibecode Smallpdf Pro
track this build5 phases, 15 steps, beginner friendly0%KINDA · weekend project
The core loop is buildable, but a dependable replacement becomes a real weekend or multi-day project. For Smallpdf Pro, offer common PDF transformations through a private self-hosted interface. The hard boundary is hosted convenience, broad tools, mobile apps, signatures, ocr, and high-volume processing, plus document fidelity, identity, and compliance.
the project pack5 files · written for this build, step by step
You are building a lean indie version of Smallpdf Pro. Create the following project files first, then implement the application by following them. Keep the files updated as decisions change. Do not collapse this into a single README or prompt. ===== README.md ===== # Smallpdf Pro · indie build Build a private PDF merge, split and rotate workbench preserving originals. Estimated effort: **multi-day**. Work `BUILD_PLAN.md` top to bottom · every phase ends in a check that has to pass before the next one starts. ## Stack | Part | Choice | Why | | --- | --- | --- | | Runtime | Python 3.12+ and Flask | A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. | | Storage | SQLite through Python sqlite3 | Local ownership with explicit transactions and a portable backup path. | | Interface | Jinja HTML templates, CSS and vanilla JavaScript | Implement the specified screens directly with labelled controls and progressive enhancement. | | Verification | Python unittest and browser acceptance fixtures | Check invariants and the actual user workflow before the next phase. | | Focused libraries | pypdf | Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. | ## Before you start Have every one of these ready. The plan assumes them from step one. - [ ] **Python 3.12 or newer and a terminal** · Python is free; this local prototype requires no hosting subscription. - Why: The local backend, tests and storage use Python. - Get it: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. - Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. - [ ] **A current desktop browser and text editor** · No paid service required for this local step. - Why: You need to view the local interface and edit generated project files. - Get it: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. - Verify: You can create a text file in the project folder and open browser developer tools. - [ ] **Smallpdf Pro acceptance sample** · No paid service required for this local step. - Why: This fixture makes the first end-to-end check reproducible. - Get it: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. - Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. - [ ] **Confirm the bounded replacement** · No paid service required for this local step. - Why: The full commercial product is larger than this guide. - Get it: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. - Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. ## Quick start ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` Then copy `.env.example` to `.env` and fill in the values it documents. ## Honest limits This build deliberately does not replace: - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem If one of those is essential to you, that is the reason to keep paying for Smallpdf Pro, and the README should say so rather than pretend. ===== BRIEF.md ===== # Build brief · Smallpdf Pro The one-shot brief this plan expands. `BUILD_PLAN.md` (or `MILESTONES.md`) is the same sequence broken into steps and checks; where the two disagree, the plan wins. Build me a private PDF merge, split and rotate workbench preserving originals as a bounded replacement for Smallpdf Pro. Build it in phases in the order below. Do not write the whole product in one pass. Finish the current phase, run its Done when checks, fix failures, then continue. Indie mode completes Phases 1-5. Phase 6 is required before shared or public deployment. ### Stack (fixed, do not substitute) - Runtime: Python 3.12+ and Flask. A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. - Storage: SQLite through Python sqlite3. Local ownership with explicit transactions and a portable backup path. - Interface: Jinja HTML templates, CSS and vanilla JavaScript. Implement the specified screens directly with labelled controls and progressive enhancement. - Verification: Python unittest and browser acceptance fixtures. Check invariants and the actual user workflow before the next phase. - Focused libraries: pypdf. Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. ### Data model (create this before Phase 1) - jobs(id,operation,status,error,created_at) - files(id,job_id,original_name,stored_path,sha256,page_count) - outputs(id,job_id,path,sha256) - operation parameters stored as validated JSON - Use stable ids and explicit relationships; add auxiliary tables named by the phases before those phases use them. - Acceptance fixture: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. ### Prerequisites and configuration - Python 3.12 or newer and a terminal: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. Cost: Python is free; this local prototype requires no hosting subscription. - A current desktop browser and text editor: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. Verify: You can create a text file in the project folder and open browser developer tools. Cost: No paid service required for this local step. - Smallpdf Pro acceptance sample: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. Cost: No paid service required for this local step. - Confirm the bounded replacement: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. Cost: No paid service required for this local step. - Configuration: DATA_DIR, SECRET_KEY, APP_MODE, SITE_URL. Ship .env.example, replace placeholders and exclude secrets from git. ### Phase 1 · Local foundation and data contract Build: Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. - Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Commands, after creating the named files: `python -m venv .venv`; `python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf`; `python -m pip freeze > requirements.txt`; `python -m flask --app app run --host 127.0.0.1`. - For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Commands, after creating the named files: `python manage.py init`; `python manage.py seed`. - Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. - Trap: The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. Done when: The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. Restarting preserves the seeded records or canonical files; running init again deletes nothing. A cross-origin state-changing request to an admin route is refused. Do not build yet: Do not start bounded pdf intake until these checks pass. ### Phase 2 · Bounded PDF intake Build: Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: PDF files are complex untrusted input; file extension alone is not validation. Done when: The malformed PDF fails with no output and leaves other jobs intact. A filename containing ../ cannot write outside the private jobs directory. Do not build yet: Do not start merge split rotate until these checks pass. ### Phase 3 · Merge split rotate Build: Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Do not claim text editing, OCR or compression quality from a page manipulation library. Done when: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Splitting page 0 or a page beyond the document is refused. Do not build yet: Do not start job isolation and cleanup until these checks pass. ### Phase 4 · Job isolation and cleanup Build: Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. Done when: One owner cannot download a second owner job by guessing its id. Expired files disappear from disk and their download returns 410 or 404. Do not build yet: Do not start portable delivery and clean-start proof until these checks pass. ### Phase 5 · Portable delivery and clean-start proof Build: Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. - Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. - Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. - Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Commands, after creating the named files: `python -m pip install -r requirements.txt`; `python -m unittest discover -s test`. - Trap: Export without an import or restore rehearsal is not verified portability. Done when: A new folder reaches the documented fixture outcome using only README instructions. A backup restored in isolation preserves the proof data and can be opened. Do not build yet: Do not start operate and share with access controls until these checks pass. ### Phase 6 · Operate and share with access controls (product-builder only) Build: Product-builder only: make a private PDF merge, split and rotate workbench preserving originals operable for its stated audience before allowing remote access. - Add owner/member/viewer authorization as appropriate, password hashes through Werkzeug, expiring server-side sessions, CSRF and login rate limits. Add users, sessions and audit schema migrations plus an owner-init command prompting securely for its password. Enforce ownership on every private read/write/download and fail closed when product setup is incomplete. Existing learner or admin identities must use this same boundary. - Serve app:app with Waitress on loopback behind Caddy HTTPS. Configure trusted proxy headers narrowly, Secure/HttpOnly/SameSite cookies, upload limits, request ids and structured logs without private content. Run background jobs as a separate supervised process when the domain workflow requires them. Commands, after creating the named files: `waitress-serve --listen=127.0.0.1:5000 app:app`. - Add a scheduled encrypted off-host backup using this procedure: Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Monitor health, disk space, failed jobs and backup age. Stop the service to test an alert; rehearse recovery with outbound effects disabled and record recovery time. Rotate any exposed credentials and require reconciliation before resuming queues. - Trap: Product mode is additional engineering, not a switch that makes a local prototype production-ready. Done when: An unauthenticated visitor cannot read private records, download private files or mutate the admin surface. A viewer cannot mutate data by making a direct request, and guessed ids cannot cross ownership boundaries. Stopping the service triggers the configured alert and the latest off-host backup restores the fixture in isolation. Do not build yet: Do not add new providers or vendor-scale features until the release gates are recorded. ### Out of scope (and why) - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing: retain the paid product if this capability is essential; it is outside this bounded build. - pixel-perfect proprietary PDF engine: retain the paid product if this capability is essential; it is outside this bounded build. - identity verification: retain the paid product if this capability is essential; it is outside this bounded build. - qualified trust services: retain the paid product if this capability is essential; it is outside this bounded build. - large template and integration ecosystem: retain the paid product if this capability is essential; it is outside this bounded build. ### README must contain - Exact install, configure, initialize, start, test and recovery commands for a clean folder. - The schema, fixture, acceptance results, private data locations and export format. - Every prerequisite and secret source, actual running costs and deliberately excluded capabilities. - An honest distinction between tests actually run and checks still awaiting real credentials or deployment. - Dependency documentation reviewed 2026-09-05: https://flask.palletsprojects.com/en/stable/installation/ ; https://docs.python.org/3/library/sqlite3.html ; https://flask-wtf.readthedocs.io/en/1.2.x/csrf/ ; https://docs.pylonsproject.org/projects/waitress/en/stable/usage.html ; https://pypdf.readthedocs.io/en/stable/user/installation.html. Recheck before upgrading; freeze the versions actually tested. ===== AGENTS.md ===== # Agent instructions · Smallpdf Pro indie build - Read `README.md` and `BUILD_PLAN.md` before writing code. The stack is fixed: Python 3.12+ and Flask, SQLite through Python sqlite3, Jinja HTML templates, CSS and vanilla JavaScript, Python unittest and browser acceptance fixtures, pypdf. Do not substitute. - Work one phase at a time, in order. Do not start a phase until every "Done when" item of the previous one passes. - Prefer the fewest moving parts that satisfy the step. No frameworks, services or dependencies the plan does not name. - Secrets live in `.env`, never in source or logs. Keep `.env.example` current when a variable is introduced. - Do not invent cryptography, security guarantees, APIs or compliance claims. - Add a focused test for every destructive, security-sensitive or data-loss path the plan names. - Run the project checks before declaring a phase complete, and record any deliberate shortcut in the README under "Tradeoffs". ## Known traps - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. - PDF files are complex untrusted input; file extension alone is not validation. - Do not claim text editing, OCR or compression quality from a page manipulation library. - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. - Export without an import or restore rehearsal is not verified portability. ===== BUILD_PLAN.md ===== # Build plan · Smallpdf Pro Build a private PDF merge, split and rotate workbench preserving originals. Phases are in dependency order. Each ends in a "Done when" list; treat an unticked item as a blocker, not a note. ## Phase 1 · Local foundation and data contract Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. ### Steps 1. Create and start the local application Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Files: `app.py`, `requirements.txt`, `.env.example`, `.gitignore` ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` 2. Implement storage and seed the named fixture For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Files: `schema.sql`, `db.py`, `manage.py`, `fixtures/README.md` ```sh python manage.py init python manage.py seed ``` 3. Protect the local request boundary Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. Files: `app.py`, `templates/base.html`, `test/test_foundation.py` ### Done when - [ ] The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. - [ ] Restarting preserves the seeded records or canonical files; running init again deletes nothing. - [ ] A cross-origin state-changing request to an admin route is refused. ### Watch out - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. ## Phase 2 · Bounded PDF intake Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. ### Steps 1. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Files: `features/bounded_pdf_intake.py`, `templates/bounded_pdf_intake.html` 2. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Files: `features/bounded_pdf_intake.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_bounded_pdf_intake.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] The malformed PDF fails with no output and leaves other jobs intact. - [ ] A filename containing ../ cannot write outside the private jobs directory. ### Watch out - PDF files are complex untrusted input; file extension alone is not validation. ## Phase 3 · Merge split rotate Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. ### Steps 1. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Files: `features/merge_split_rotate.py`, `templates/merge_split_rotate.html` 2. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Files: `features/merge_split_rotate.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_merge_split_rotate.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - [ ] Splitting page 0 or a page beyond the document is refused. ### Watch out - Do not claim text editing, OCR or compression quality from a page manipulation library. ## Phase 4 · Job isolation and cleanup Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. ### Steps 1. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Files: `features/job_isolation_and_cleanup.py`, `templates/job_isolation_and_cleanup.html` 2. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Files: `features/job_isolation_and_cleanup.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_job_isolation_and_cleanup.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] One owner cannot download a second owner job by guessing its id. - [ ] Expired files disappear from disk and their download returns 410 or 404. ### Watch out - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. ## Phase 5 · Portable delivery and clean-start proof Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. ### Steps 1. Write the user-facing runbook Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. Files: `README.md`, `.env.example` 2. Create and rehearse a recoverable backup Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. Files: `OPERATIONS.md`, `scripts/backup.py` 3. Reproduce the first-run experience Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Files: `README.md`, `verification.md` ```sh python -m pip install -r requirements.txt python -m unittest discover -s test ``` ### Done when - [ ] A new folder reaches the documented fixture outcome using only README instructions. - [ ] A backup restored in isolation preserves the proof data and can be opened. ### Watch out - Export without an import or restore rehearsal is not verified portability. ## Not in this build - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem ## After v1, if you want it - Extend job isolation and cleanup only after the fixture and recovery checks pass. - Before adding another integration, document its credentials, limits, cost and failure behavior with primary-source links. ===== .env.example ===== # Copy to .env and fill in. Never commit .env; this file documents it. # Required. A new private folder this application creates on first run; never serve it as static files. DATA_DIR=./data/smallpdf # Required · secret. Generate with python -c "import secrets; print(secrets.token_hex(32))" and save only in .env. SECRET_KEY=replace-with-a-random-secret # Required. Use indie for loopback-only personal work. Product mode must refuse to start until owner login and the deployment gates are configured. APP_MODE=indie # Required. The origin used for local forms and links; replace with the chosen HTTPS origin in product mode. SITE_URL=http://127.0.0.1:5000
You are building a lean indie version of Smallpdf Pro. Create the following project files first, then implement the application by following them. Keep the files updated as decisions change. Do not collapse this into a single README or prompt. ===== README.md ===== # Smallpdf Pro · indie build Build a private PDF merge, split and rotate workbench preserving originals. Estimated effort: **multi-day**. Work `BUILD_PLAN.md` top to bottom · every phase ends in a check that has to pass before the next one starts. ## Stack | Part | Choice | Why | | --- | --- | --- | | Runtime | Python 3.12+ and Flask | A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. | | Storage | SQLite through Python sqlite3 | Local ownership with explicit transactions and a portable backup path. | | Interface | Jinja HTML templates, CSS and vanilla JavaScript | Implement the specified screens directly with labelled controls and progressive enhancement. | | Verification | Python unittest and browser acceptance fixtures | Check invariants and the actual user workflow before the next phase. | | Focused libraries | pypdf | Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. | ## Before you start Have every one of these ready. The plan assumes them from step one. - [ ] **Python 3.12 or newer and a terminal** · Python is free; this local prototype requires no hosting subscription. - Why: The local backend, tests and storage use Python. - Get it: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. - Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. - [ ] **A current desktop browser and text editor** · No paid service required for this local step. - Why: You need to view the local interface and edit generated project files. - Get it: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. - Verify: You can create a text file in the project folder and open browser developer tools. - [ ] **Smallpdf Pro acceptance sample** · No paid service required for this local step. - Why: This fixture makes the first end-to-end check reproducible. - Get it: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. - Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. - [ ] **Confirm the bounded replacement** · No paid service required for this local step. - Why: The full commercial product is larger than this guide. - Get it: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. - Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. ## Quick start ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` Then copy `.env.example` to `.env` and fill in the values it documents. ## Honest limits This build deliberately does not replace: - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem If one of those is essential to you, that is the reason to keep paying for Smallpdf Pro, and the README should say so rather than pretend. ===== BRIEF.md ===== # Build brief · Smallpdf Pro The one-shot brief this plan expands. `BUILD_PLAN.md` (or `MILESTONES.md`) is the same sequence broken into steps and checks; where the two disagree, the plan wins. Build me a private PDF merge, split and rotate workbench preserving originals as a bounded replacement for Smallpdf Pro. Build it in phases in the order below. Do not write the whole product in one pass. Finish the current phase, run its Done when checks, fix failures, then continue. Indie mode completes Phases 1-5. Phase 6 is required before shared or public deployment. ### Stack (fixed, do not substitute) - Runtime: Python 3.12+ and Flask. A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. - Storage: SQLite through Python sqlite3. Local ownership with explicit transactions and a portable backup path. - Interface: Jinja HTML templates, CSS and vanilla JavaScript. Implement the specified screens directly with labelled controls and progressive enhancement. - Verification: Python unittest and browser acceptance fixtures. Check invariants and the actual user workflow before the next phase. - Focused libraries: pypdf. Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. ### Data model (create this before Phase 1) - jobs(id,operation,status,error,created_at) - files(id,job_id,original_name,stored_path,sha256,page_count) - outputs(id,job_id,path,sha256) - operation parameters stored as validated JSON - Use stable ids and explicit relationships; add auxiliary tables named by the phases before those phases use them. - Acceptance fixture: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. ### Prerequisites and configuration - Python 3.12 or newer and a terminal: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. Cost: Python is free; this local prototype requires no hosting subscription. - A current desktop browser and text editor: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. Verify: You can create a text file in the project folder and open browser developer tools. Cost: No paid service required for this local step. - Smallpdf Pro acceptance sample: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. Cost: No paid service required for this local step. - Confirm the bounded replacement: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. Cost: No paid service required for this local step. - Configuration: DATA_DIR, SECRET_KEY, APP_MODE, SITE_URL. Ship .env.example, replace placeholders and exclude secrets from git. ### Phase 1 · Local foundation and data contract Build: Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. - Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Commands, after creating the named files: `python -m venv .venv`; `python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf`; `python -m pip freeze > requirements.txt`; `python -m flask --app app run --host 127.0.0.1`. - For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Commands, after creating the named files: `python manage.py init`; `python manage.py seed`. - Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. - Trap: The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. Done when: The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. Restarting preserves the seeded records or canonical files; running init again deletes nothing. A cross-origin state-changing request to an admin route is refused. Do not build yet: Do not start bounded pdf intake until these checks pass. ### Phase 2 · Bounded PDF intake Build: Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: PDF files are complex untrusted input; file extension alone is not validation. Done when: The malformed PDF fails with no output and leaves other jobs intact. A filename containing ../ cannot write outside the private jobs directory. Do not build yet: Do not start merge split rotate until these checks pass. ### Phase 3 · Merge split rotate Build: Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Do not claim text editing, OCR or compression quality from a page manipulation library. Done when: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Splitting page 0 or a page beyond the document is refused. Do not build yet: Do not start job isolation and cleanup until these checks pass. ### Phase 4 · Job isolation and cleanup Build: Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. Done when: One owner cannot download a second owner job by guessing its id. Expired files disappear from disk and their download returns 410 or 404. Do not build yet: Do not start portable delivery and clean-start proof until these checks pass. ### Phase 5 · Portable delivery and clean-start proof Build: Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. - Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. - Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. - Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Commands, after creating the named files: `python -m pip install -r requirements.txt`; `python -m unittest discover -s test`. - Trap: Export without an import or restore rehearsal is not verified portability. Done when: A new folder reaches the documented fixture outcome using only README instructions. A backup restored in isolation preserves the proof data and can be opened. Do not build yet: Do not start operate and share with access controls until these checks pass. ### Phase 6 · Operate and share with access controls (product-builder only) Build: Product-builder only: make a private PDF merge, split and rotate workbench preserving originals operable for its stated audience before allowing remote access. - Add owner/member/viewer authorization as appropriate, password hashes through Werkzeug, expiring server-side sessions, CSRF and login rate limits. Add users, sessions and audit schema migrations plus an owner-init command prompting securely for its password. Enforce ownership on every private read/write/download and fail closed when product setup is incomplete. Existing learner or admin identities must use this same boundary. - Serve app:app with Waitress on loopback behind Caddy HTTPS. Configure trusted proxy headers narrowly, Secure/HttpOnly/SameSite cookies, upload limits, request ids and structured logs without private content. Run background jobs as a separate supervised process when the domain workflow requires them. Commands, after creating the named files: `waitress-serve --listen=127.0.0.1:5000 app:app`. - Add a scheduled encrypted off-host backup using this procedure: Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Monitor health, disk space, failed jobs and backup age. Stop the service to test an alert; rehearse recovery with outbound effects disabled and record recovery time. Rotate any exposed credentials and require reconciliation before resuming queues. - Trap: Product mode is additional engineering, not a switch that makes a local prototype production-ready. Done when: An unauthenticated visitor cannot read private records, download private files or mutate the admin surface. A viewer cannot mutate data by making a direct request, and guessed ids cannot cross ownership boundaries. Stopping the service triggers the configured alert and the latest off-host backup restores the fixture in isolation. Do not build yet: Do not add new providers or vendor-scale features until the release gates are recorded. ### Out of scope (and why) - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing: retain the paid product if this capability is essential; it is outside this bounded build. - pixel-perfect proprietary PDF engine: retain the paid product if this capability is essential; it is outside this bounded build. - identity verification: retain the paid product if this capability is essential; it is outside this bounded build. - qualified trust services: retain the paid product if this capability is essential; it is outside this bounded build. - large template and integration ecosystem: retain the paid product if this capability is essential; it is outside this bounded build. ### README must contain - Exact install, configure, initialize, start, test and recovery commands for a clean folder. - The schema, fixture, acceptance results, private data locations and export format. - Every prerequisite and secret source, actual running costs and deliberately excluded capabilities. - An honest distinction between tests actually run and checks still awaiting real credentials or deployment. - Dependency documentation reviewed 2026-09-05: https://flask.palletsprojects.com/en/stable/installation/ ; https://docs.python.org/3/library/sqlite3.html ; https://flask-wtf.readthedocs.io/en/1.2.x/csrf/ ; https://docs.pylonsproject.org/projects/waitress/en/stable/usage.html ; https://pypdf.readthedocs.io/en/stable/user/installation.html. Recheck before upgrading; freeze the versions actually tested. ===== AGENTS.md ===== # Agent instructions · Smallpdf Pro indie build - Read `README.md` and `BUILD_PLAN.md` before writing code. The stack is fixed: Python 3.12+ and Flask, SQLite through Python sqlite3, Jinja HTML templates, CSS and vanilla JavaScript, Python unittest and browser acceptance fixtures, pypdf. Do not substitute. - Work one phase at a time, in order. Do not start a phase until every "Done when" item of the previous one passes. - Prefer the fewest moving parts that satisfy the step. No frameworks, services or dependencies the plan does not name. - Secrets live in `.env`, never in source or logs. Keep `.env.example` current when a variable is introduced. - Do not invent cryptography, security guarantees, APIs or compliance claims. - Add a focused test for every destructive, security-sensitive or data-loss path the plan names. - Run the project checks before declaring a phase complete, and record any deliberate shortcut in the README under "Tradeoffs". ## Known traps - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. - PDF files are complex untrusted input; file extension alone is not validation. - Do not claim text editing, OCR or compression quality from a page manipulation library. - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. - Export without an import or restore rehearsal is not verified portability. ===== BUILD_PLAN.md ===== # Build plan · Smallpdf Pro Build a private PDF merge, split and rotate workbench preserving originals. Phases are in dependency order. Each ends in a "Done when" list; treat an unticked item as a blocker, not a note. ## Phase 1 · Local foundation and data contract Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. ### Steps 1. Create and start the local application Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Files: `app.py`, `requirements.txt`, `.env.example`, `.gitignore` ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` 2. Implement storage and seed the named fixture For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Files: `schema.sql`, `db.py`, `manage.py`, `fixtures/README.md` ```sh python manage.py init python manage.py seed ``` 3. Protect the local request boundary Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. Files: `app.py`, `templates/base.html`, `test/test_foundation.py` ### Done when - [ ] The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. - [ ] Restarting preserves the seeded records or canonical files; running init again deletes nothing. - [ ] A cross-origin state-changing request to an admin route is refused. ### Watch out - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. ## Phase 2 · Bounded PDF intake Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. ### Steps 1. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Files: `features/bounded_pdf_intake.py`, `templates/bounded_pdf_intake.html` 2. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Files: `features/bounded_pdf_intake.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_bounded_pdf_intake.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] The malformed PDF fails with no output and leaves other jobs intact. - [ ] A filename containing ../ cannot write outside the private jobs directory. ### Watch out - PDF files are complex untrusted input; file extension alone is not validation. ## Phase 3 · Merge split rotate Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. ### Steps 1. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Files: `features/merge_split_rotate.py`, `templates/merge_split_rotate.html` 2. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Files: `features/merge_split_rotate.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_merge_split_rotate.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - [ ] Splitting page 0 or a page beyond the document is refused. ### Watch out - Do not claim text editing, OCR or compression quality from a page manipulation library. ## Phase 4 · Job isolation and cleanup Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. ### Steps 1. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Files: `features/job_isolation_and_cleanup.py`, `templates/job_isolation_and_cleanup.html` 2. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Files: `features/job_isolation_and_cleanup.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_job_isolation_and_cleanup.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] One owner cannot download a second owner job by guessing its id. - [ ] Expired files disappear from disk and their download returns 410 or 404. ### Watch out - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. ## Phase 5 · Portable delivery and clean-start proof Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. ### Steps 1. Write the user-facing runbook Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. Files: `README.md`, `.env.example` 2. Create and rehearse a recoverable backup Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. Files: `OPERATIONS.md`, `scripts/backup.py` 3. Reproduce the first-run experience Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Files: `README.md`, `verification.md` ```sh python -m pip install -r requirements.txt python -m unittest discover -s test ``` ### Done when - [ ] A new folder reaches the documented fixture outcome using only README instructions. - [ ] A backup restored in isolation preserves the proof data and can be opened. ### Watch out - Export without an import or restore rehearsal is not verified portability. ## Not in this build - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem ## After v1, if you want it - Extend job isolation and cleanup only after the fixture and recovery checks pass. - Before adding another integration, document its credentials, limits, cost and failure behavior with primary-source links. ===== .env.example ===== # Copy to .env and fill in. Never commit .env; this file documents it. # Required. A new private folder this application creates on first run; never serve it as static files. DATA_DIR=./data/smallpdf # Required · secret. Generate with python -c "import secrets; print(secrets.token_hex(32))" and save only in .env. SECRET_KEY=replace-with-a-random-secret # Required. Use indie for loopback-only personal work. Product mode must refuse to start until owner login and the deployment gates are configured. APP_MODE=indie # Required. The origin used for local forms and links; replace with the chosen HTTPS origin in product mode. SITE_URL=http://127.0.0.1:5000
You are building a production product version of Smallpdf Pro. Create the following project files first, then implement the application by following them. Keep the files updated as decisions change. Do not collapse this into a single README or prompt. ===== PRODUCT.md ===== # Smallpdf Pro · product brief ## Problem The core loop is buildable, but a dependable replacement becomes a real weekend or multi-day project. For Smallpdf Pro, offer common PDF transformations through a private self-hosted interface. The hard boundary is hosted convenience, broad tools, mobile apps, signatures, ocr, and high-volume processing, plus document fidelity, identity, and compliance. ## Product outcome An operated version of a private PDF merge, split and rotate workbench preserving originals, with authorized access, restore evidence and honest scope limits. ## Target user A builder who needs a maintainable product foundation, not a one-off demo. ## Required capabilities - Docker - PostgreSQL - LibreOffice headless - local or S3-compatible storage - public HTTPS for signature links ## Explicit non-goals for v1 - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem ## Success criteria - The malformed PDF fails with no output and leaves other jobs intact. - Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - One owner cannot download a second owner job by guessing its id. - A private-data authorization check passes using a second identity. - An off-host restore drill has a date, observed result and recovery time in OPERATIONS.md. - README names the excluded vendor capabilities and actual provider/hosting costs. ===== BRIEF.md ===== # Build brief · Smallpdf Pro The one-shot brief this plan expands. `BUILD_PLAN.md` (or `MILESTONES.md`) is the same sequence broken into steps and checks; where the two disagree, the plan wins. Build me a private PDF merge, split and rotate workbench preserving originals as a bounded replacement for Smallpdf Pro. Build it in phases in the order below. Do not write the whole product in one pass. Finish the current phase, run its Done when checks, fix failures, then continue. Indie mode completes Phases 1-5. Phase 6 is required before shared or public deployment. ### Stack (fixed, do not substitute) - Runtime: Python 3.12+ and Flask. A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. - Storage: SQLite through Python sqlite3. Local ownership with explicit transactions and a portable backup path. - Interface: Jinja HTML templates, CSS and vanilla JavaScript. Implement the specified screens directly with labelled controls and progressive enhancement. - Verification: Python unittest and browser acceptance fixtures. Check invariants and the actual user workflow before the next phase. - Focused libraries: pypdf. Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. ### Data model (create this before Phase 1) - jobs(id,operation,status,error,created_at) - files(id,job_id,original_name,stored_path,sha256,page_count) - outputs(id,job_id,path,sha256) - operation parameters stored as validated JSON - Use stable ids and explicit relationships; add auxiliary tables named by the phases before those phases use them. - Acceptance fixture: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. ### Prerequisites and configuration - Python 3.12 or newer and a terminal: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. Cost: Python is free; this local prototype requires no hosting subscription. - A current desktop browser and text editor: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. Verify: You can create a text file in the project folder and open browser developer tools. Cost: No paid service required for this local step. - Smallpdf Pro acceptance sample: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. Cost: No paid service required for this local step. - Confirm the bounded replacement: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. Cost: No paid service required for this local step. - Configuration: DATA_DIR, SECRET_KEY, APP_MODE, SITE_URL. Ship .env.example, replace placeholders and exclude secrets from git. ### Phase 1 · Local foundation and data contract Build: Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. - Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Commands, after creating the named files: `python -m venv .venv`; `python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf`; `python -m pip freeze > requirements.txt`; `python -m flask --app app run --host 127.0.0.1`. - For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Commands, after creating the named files: `python manage.py init`; `python manage.py seed`. - Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. - Trap: The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. Done when: The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. Restarting preserves the seeded records or canonical files; running init again deletes nothing. A cross-origin state-changing request to an admin route is refused. Do not build yet: Do not start bounded pdf intake until these checks pass. ### Phase 2 · Bounded PDF intake Build: Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: PDF files are complex untrusted input; file extension alone is not validation. Done when: The malformed PDF fails with no output and leaves other jobs intact. A filename containing ../ cannot write outside the private jobs directory. Do not build yet: Do not start merge split rotate until these checks pass. ### Phase 3 · Merge split rotate Build: Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Do not claim text editing, OCR or compression quality from a page manipulation library. Done when: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Splitting page 0 or a page beyond the document is refused. Do not build yet: Do not start job isolation and cleanup until these checks pass. ### Phase 4 · Job isolation and cleanup Build: Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. Done when: One owner cannot download a second owner job by guessing its id. Expired files disappear from disk and their download returns 410 or 404. Do not build yet: Do not start portable delivery and clean-start proof until these checks pass. ### Phase 5 · Portable delivery and clean-start proof Build: Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. - Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. - Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. - Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Commands, after creating the named files: `python -m pip install -r requirements.txt`; `python -m unittest discover -s test`. - Trap: Export without an import or restore rehearsal is not verified portability. Done when: A new folder reaches the documented fixture outcome using only README instructions. A backup restored in isolation preserves the proof data and can be opened. Do not build yet: Do not start operate and share with access controls until these checks pass. ### Phase 6 · Operate and share with access controls (product-builder only) Build: Product-builder only: make a private PDF merge, split and rotate workbench preserving originals operable for its stated audience before allowing remote access. - Add owner/member/viewer authorization as appropriate, password hashes through Werkzeug, expiring server-side sessions, CSRF and login rate limits. Add users, sessions and audit schema migrations plus an owner-init command prompting securely for its password. Enforce ownership on every private read/write/download and fail closed when product setup is incomplete. Existing learner or admin identities must use this same boundary. - Serve app:app with Waitress on loopback behind Caddy HTTPS. Configure trusted proxy headers narrowly, Secure/HttpOnly/SameSite cookies, upload limits, request ids and structured logs without private content. Run background jobs as a separate supervised process when the domain workflow requires them. Commands, after creating the named files: `waitress-serve --listen=127.0.0.1:5000 app:app`. - Add a scheduled encrypted off-host backup using this procedure: Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Monitor health, disk space, failed jobs and backup age. Stop the service to test an alert; rehearse recovery with outbound effects disabled and record recovery time. Rotate any exposed credentials and require reconciliation before resuming queues. - Trap: Product mode is additional engineering, not a switch that makes a local prototype production-ready. Done when: An unauthenticated visitor cannot read private records, download private files or mutate the admin surface. A viewer cannot mutate data by making a direct request, and guessed ids cannot cross ownership boundaries. Stopping the service triggers the configured alert and the latest off-host backup restores the fixture in isolation. Do not build yet: Do not add new providers or vendor-scale features until the release gates are recorded. ### Out of scope (and why) - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing: retain the paid product if this capability is essential; it is outside this bounded build. - pixel-perfect proprietary PDF engine: retain the paid product if this capability is essential; it is outside this bounded build. - identity verification: retain the paid product if this capability is essential; it is outside this bounded build. - qualified trust services: retain the paid product if this capability is essential; it is outside this bounded build. - large template and integration ecosystem: retain the paid product if this capability is essential; it is outside this bounded build. ### README must contain - Exact install, configure, initialize, start, test and recovery commands for a clean folder. - The schema, fixture, acceptance results, private data locations and export format. - Every prerequisite and secret source, actual running costs and deliberately excluded capabilities. - An honest distinction between tests actually run and checks still awaiting real credentials or deployment. - Dependency documentation reviewed 2026-09-05: https://flask.palletsprojects.com/en/stable/installation/ ; https://docs.python.org/3/library/sqlite3.html ; https://flask-wtf.readthedocs.io/en/1.2.x/csrf/ ; https://docs.pylonsproject.org/projects/waitress/en/stable/usage.html ; https://pypdf.readthedocs.io/en/stable/user/installation.html. Recheck before upgrading; freeze the versions actually tested. ===== ARCHITECTURE.md ===== # Architecture · Smallpdf Pro ## Stack | Part | Choice | Why | | --- | --- | --- | | Runtime | Python 3.12+ and Flask | A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. | | Storage | SQLite through Python sqlite3 | Local ownership with explicit transactions and a portable backup path. | | Interface | Jinja HTML templates, CSS and vanilla JavaScript | Implement the specified screens directly with labelled controls and progressive enhancement. | | Verification | Python unittest and browser acceptance fixtures | Check invariants and the actual user workflow before the next phase. | | Focused libraries | pypdf | Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. | ## Modules Each module has one owner concern and a documented way to replace it. | Module | Owns | How to replace it | | --- | --- | --- | | Data and identity | jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON | Keep stable ids and a versioned repository interface; migrate storage behind it with a fixture round-trip. | | Bounded PDF intake | Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. | Keep the acceptance contract: The malformed PDF fails with no output and leaves other jobs intact. Replace only this module after replaying its fixture; preserve ids and existing records. | | Merge split rotate | Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. | Keep the acceptance contract: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Replace only this module after replaying its fixture; preserve ids and existing records. | | Job isolation and cleanup | Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. | Keep the acceptance contract: One owner cannot download a second owner job by guessing its id. Replace only this module after replaying its fixture; preserve ids and existing records. | | Operations | Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. | Change host or backup destination only after an isolated restore and authorization check. | ## Configuration Every runtime setting is an environment variable documented in `.env.example`, validated at startup, with a safe local default wherever one exists. - `DATA_DIR` · required · A new private folder this application creates on first run; never serve it as static files. - `SECRET_KEY` · required, secret · Generate with python -c "import secrets; print(secrets.token_hex(32))" and save only in .env. - `APP_MODE` · required · Use indie for loopback-only personal work. Product mode must refuse to start until owner login and the deployment gates are configured. - `SITE_URL` · required · The origin used for local forms and links; replace with the chosen HTTPS origin in product mode. ## Production baseline - Security: least privilege, input validation at every boundary, secret redaction in logs, rate limits on abuse-prone paths, no invented security primitives. - Data: explicit schema and migrations, transactional writes where integrity matters, backup and restore procedures that have been exercised. - Integrations: adapters around third-party providers, idempotent webhook or job processing, bounded retries, timeouts. - Observability: structured logs with request or operation ids, an error-tracking hook, and health and readiness checks where a server exists. - Quality: unit tests for domain rules, integration tests at module boundaries, one end-to-end test of the critical path. ## Decision records For each dependency in the stack table, keep a short note: why it was chosen, its failure mode, and how it is replaced. Do not add infrastructure until a requirement in `PRODUCT.md` justifies it. ===== AGENTS.md ===== # Agent instructions · Smallpdf Pro product build - Read `PRODUCT.md` and `ARCHITECTURE.md` before changing code. The stack is fixed: Python 3.12+ and Flask, SQLite through Python sqlite3, Jinja HTML templates, CSS and vanilla JavaScript, Python unittest and browser acceptance fixtures, pypdf. - Implement milestone by milestone from `MILESTONES.md`; keep each change reviewable and leave the application runnable at every commit. - Treat authentication, payments, encryption, imports, webhooks and destructive actions as high-risk boundaries when present. - Never invent cryptography or silently weaken a requirement to make a check pass. - Put every external service behind an interface with a deterministic fake for tests. - Add migrations and rollback or recovery notes for every persistent data change. - Log useful operational context without credentials, tokens, passwords or personal data. - Update documentation and run every check before completing a milestone. ## Known traps - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. - PDF files are complex untrusted input; file extension alone is not validation. - Do not claim text editing, OCR or compression quality from a page manipulation library. - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. - Export without an import or restore rehearsal is not verified portability. - Product mode is additional engineering, not a switch that makes a local prototype production-ready. ===== MILESTONES.md ===== # Delivery milestones · Smallpdf Pro Estimated effort: **multi-day** for the indie phases; the production-only milestones add the trust and operability layer. ## M1 · Local foundation and data contract Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. ### Steps 1. Create and start the local application Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Files: `app.py`, `requirements.txt`, `.env.example`, `.gitignore` ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` 2. Implement storage and seed the named fixture For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Files: `schema.sql`, `db.py`, `manage.py`, `fixtures/README.md` ```sh python manage.py init python manage.py seed ``` 3. Protect the local request boundary Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. Files: `app.py`, `templates/base.html`, `test/test_foundation.py` ### Done when - [ ] The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. - [ ] Restarting preserves the seeded records or canonical files; running init again deletes nothing. - [ ] A cross-origin state-changing request to an admin route is refused. ### Watch out - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. ## M2 · Bounded PDF intake Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. ### Steps 1. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Files: `features/bounded_pdf_intake.py`, `templates/bounded_pdf_intake.html` 2. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Files: `features/bounded_pdf_intake.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_bounded_pdf_intake.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] The malformed PDF fails with no output and leaves other jobs intact. - [ ] A filename containing ../ cannot write outside the private jobs directory. ### Watch out - PDF files are complex untrusted input; file extension alone is not validation. ## M3 · Merge split rotate Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. ### Steps 1. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Files: `features/merge_split_rotate.py`, `templates/merge_split_rotate.html` 2. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Files: `features/merge_split_rotate.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_merge_split_rotate.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - [ ] Splitting page 0 or a page beyond the document is refused. ### Watch out - Do not claim text editing, OCR or compression quality from a page manipulation library. ## M4 · Job isolation and cleanup Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. ### Steps 1. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Files: `features/job_isolation_and_cleanup.py`, `templates/job_isolation_and_cleanup.html` 2. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Files: `features/job_isolation_and_cleanup.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_job_isolation_and_cleanup.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] One owner cannot download a second owner job by guessing its id. - [ ] Expired files disappear from disk and their download returns 410 or 404. ### Watch out - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. ## M5 · Portable delivery and clean-start proof Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. ### Steps 1. Write the user-facing runbook Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. Files: `README.md`, `.env.example` 2. Create and rehearse a recoverable backup Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. Files: `OPERATIONS.md`, `scripts/backup.py` 3. Reproduce the first-run experience Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Files: `README.md`, `verification.md` ```sh python -m pip install -r requirements.txt python -m unittest discover -s test ``` ### Done when - [ ] A new folder reaches the documented fixture outcome using only README instructions. - [ ] A backup restored in isolation preserves the proof data and can be opened. ### Watch out - Export without an import or restore rehearsal is not verified portability. ## M6 · Operate and share with access controls (production only) Product-builder only: make a private PDF merge, split and rotate workbench preserving originals operable for its stated audience before allowing remote access. ### Steps 1. Establish owner access before exposure Add owner/member/viewer authorization as appropriate, password hashes through Werkzeug, expiring server-side sessions, CSRF and login rate limits. Add users, sessions and audit schema migrations plus an owner-init command prompting securely for its password. Enforce ownership on every private read/write/download and fail closed when product setup is incomplete. Existing learner or admin identities must use this same boundary. Files: `ARCHITECTURE.md`, `OPERATIONS.md` 2. Deploy a monitored service Serve app:app with Waitress on loopback behind Caddy HTTPS. Configure trusted proxy headers narrowly, Secure/HttpOnly/SameSite cookies, upload limits, request ids and structured logs without private content. Run background jobs as a separate supervised process when the domain workflow requires them. Files: `Caddyfile`, `OPERATIONS.md` ```sh waitress-serve --listen=127.0.0.1:5000 app:app ``` 3. Rehearse loss and recovery Add a scheduled encrypted off-host backup using this procedure: Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Monitor health, disk space, failed jobs and backup age. Stop the service to test an alert; rehearse recovery with outbound effects disabled and record recovery time. Rotate any exposed credentials and require reconciliation before resuming queues. Files: `OPERATIONS.md`, `release-checklist.md` ### Done when - [ ] An unauthenticated visitor cannot read private records, download private files or mutate the admin surface. - [ ] A viewer cannot mutate data by making a direct request, and guessed ids cannot cross ownership boundaries. - [ ] Stopping the service triggers the configured alert and the latest off-host backup restores the fixture in isolation. ### Watch out - Product mode is additional engineering, not a switch that makes a local prototype production-ready. ===== OPERATIONS.md ===== # Operations · Smallpdf Pro ## Backup Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. ## Restore Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. Do a restore drill before the first real user, and write the date here when it passes. ## Monitoring Check HTTP availability, free disk, backup age and domain failures for Bounded PDF intake, Merge split rotate, Job isolation and cleanup. Alert without logging private payloads. ## Incident checklist Pause outbound jobs and public intake as appropriate, preserve redacted diagnostics, restore an isolated verified backup, rotate affected credentials and reconcile uncertain effects before reopening. 1. Contain the issue without destroying evidence or user data. 2. Record the timeline and affected scope. 3. Rotate exposed secrets and revoke compromised sessions or credentials. 4. Restore from a verified backup when needed. 5. Document the root cause, the remediation and the regression test. ## Release gate - [ ] The malformed PDF fails with no output and leaves other jobs intact. - [ ] Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - [ ] One owner cannot download a second owner job by guessing its id. - [ ] A private-data authorization check passes using a second identity. - [ ] An off-host restore drill has a date, observed result and recovery time in OPERATIONS.md. - [ ] README names the excluded vendor capabilities and actual provider/hosting costs. ## Launch constraint Do not market omitted Smallpdf Pro capabilities as implemented. The non-goals in `PRODUCT.md` remain user-visible limitations until they are deliberately delivered. ===== .env.example ===== # Copy to .env and fill in. Never commit .env; this file documents it. # Required. A new private folder this application creates on first run; never serve it as static files. DATA_DIR=./data/smallpdf # Required · secret. Generate with python -c "import secrets; print(secrets.token_hex(32))" and save only in .env. SECRET_KEY=replace-with-a-random-secret # Required. Use indie for loopback-only personal work. Product mode must refuse to start until owner login and the deployment gates are configured. APP_MODE=indie # Required. The origin used for local forms and links; replace with the chosen HTTPS origin in product mode. SITE_URL=http://127.0.0.1:5000
README.md
# Smallpdf Pro · indie build Build a private PDF merge, split and rotate workbench preserving originals. Estimated effort: **multi-day**. Work `BUILD_PLAN.md` top to bottom · every phase ends in a check that has to pass before the next one starts. ## Stack | Part | Choice | Why | | --- | --- | --- | | Runtime | Python 3.12+ and Flask | A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. | | Storage | SQLite through Python sqlite3 | Local ownership with explicit transactions and a portable backup path. | | Interface | Jinja HTML templates, CSS and vanilla JavaScript | Implement the specified screens directly with labelled controls and progressive enhancement. | | Verification | Python unittest and browser acceptance fixtures | Check invariants and the actual user workflow before the next phase. | | Focused libraries | pypdf | Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. | ## Before you start Have every one of these ready. The plan assumes them from step one. - [ ] **Python 3.12 or newer and a terminal** · Python is free; this local prototype requires no hosting subscription. - Why: The local backend, tests and storage use Python. - Get it: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. - Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. - [ ] **A current desktop browser and text editor** · No paid service required for this local step. - Why: You need to view the local interface and edit generated project files. - Get it: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. - Verify: You can create a text file in the project folder and open browser developer tools. - [ ] **Smallpdf Pro acceptance sample** · No paid service required for this local step. - Why: This fixture makes the first end-to-end check reproducible. - Get it: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. - Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. - [ ] **Confirm the bounded replacement** · No paid service required for this local step. - Why: The full commercial product is larger than this guide. - Get it: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. - Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. ## Quick start ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` Then copy `.env.example` to `.env` and fill in the values it documents. ## Honest limits This build deliberately does not replace: - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem If one of those is essential to you, that is the reason to keep paying for Smallpdf Pro, and the README should say so rather than pretend.
BRIEF.md
# Build brief · Smallpdf Pro The one-shot brief this plan expands. `BUILD_PLAN.md` (or `MILESTONES.md`) is the same sequence broken into steps and checks; where the two disagree, the plan wins. Build me a private PDF merge, split and rotate workbench preserving originals as a bounded replacement for Smallpdf Pro. Build it in phases in the order below. Do not write the whole product in one pass. Finish the current phase, run its Done when checks, fix failures, then continue. Indie mode completes Phases 1-5. Phase 6 is required before shared or public deployment. ### Stack (fixed, do not substitute) - Runtime: Python 3.12+ and Flask. A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. - Storage: SQLite through Python sqlite3. Local ownership with explicit transactions and a portable backup path. - Interface: Jinja HTML templates, CSS and vanilla JavaScript. Implement the specified screens directly with labelled controls and progressive enhancement. - Verification: Python unittest and browser acceptance fixtures. Check invariants and the actual user workflow before the next phase. - Focused libraries: pypdf. Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. ### Data model (create this before Phase 1) - jobs(id,operation,status,error,created_at) - files(id,job_id,original_name,stored_path,sha256,page_count) - outputs(id,job_id,path,sha256) - operation parameters stored as validated JSON - Use stable ids and explicit relationships; add auxiliary tables named by the phases before those phases use them. - Acceptance fixture: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. ### Prerequisites and configuration - Python 3.12 or newer and a terminal: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. Cost: Python is free; this local prototype requires no hosting subscription. - A current desktop browser and text editor: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. Verify: You can create a text file in the project folder and open browser developer tools. Cost: No paid service required for this local step. - Smallpdf Pro acceptance sample: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. Cost: No paid service required for this local step. - Confirm the bounded replacement: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. Cost: No paid service required for this local step. - Configuration: DATA_DIR, SECRET_KEY, APP_MODE, SITE_URL. Ship .env.example, replace placeholders and exclude secrets from git. ### Phase 1 · Local foundation and data contract Build: Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. - Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Commands, after creating the named files: `python -m venv .venv`; `python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf`; `python -m pip freeze > requirements.txt`; `python -m flask --app app run --host 127.0.0.1`. - For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Commands, after creating the named files: `python manage.py init`; `python manage.py seed`. - Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. - Trap: The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. Done when: The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. Restarting preserves the seeded records or canonical files; running init again deletes nothing. A cross-origin state-changing request to an admin route is refused. Do not build yet: Do not start bounded pdf intake until these checks pass. ### Phase 2 · Bounded PDF intake Build: Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: PDF files are complex untrusted input; file extension alone is not validation. Done when: The malformed PDF fails with no output and leaves other jobs intact. A filename containing ../ cannot write outside the private jobs directory. Do not build yet: Do not start merge split rotate until these checks pass. ### Phase 3 · Merge split rotate Build: Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Do not claim text editing, OCR or compression quality from a page manipulation library. Done when: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Splitting page 0 or a page beyond the document is refused. Do not build yet: Do not start job isolation and cleanup until these checks pass. ### Phase 4 · Job isolation and cleanup Build: Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. Done when: One owner cannot download a second owner job by guessing its id. Expired files disappear from disk and their download returns 410 or 404. Do not build yet: Do not start portable delivery and clean-start proof until these checks pass. ### Phase 5 · Portable delivery and clean-start proof Build: Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. - Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. - Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. - Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Commands, after creating the named files: `python -m pip install -r requirements.txt`; `python -m unittest discover -s test`. - Trap: Export without an import or restore rehearsal is not verified portability. Done when: A new folder reaches the documented fixture outcome using only README instructions. A backup restored in isolation preserves the proof data and can be opened. Do not build yet: Do not start operate and share with access controls until these checks pass. ### Phase 6 · Operate and share with access controls (product-builder only) Build: Product-builder only: make a private PDF merge, split and rotate workbench preserving originals operable for its stated audience before allowing remote access. - Add owner/member/viewer authorization as appropriate, password hashes through Werkzeug, expiring server-side sessions, CSRF and login rate limits. Add users, sessions and audit schema migrations plus an owner-init command prompting securely for its password. Enforce ownership on every private read/write/download and fail closed when product setup is incomplete. Existing learner or admin identities must use this same boundary. - Serve app:app with Waitress on loopback behind Caddy HTTPS. Configure trusted proxy headers narrowly, Secure/HttpOnly/SameSite cookies, upload limits, request ids and structured logs without private content. Run background jobs as a separate supervised process when the domain workflow requires them. Commands, after creating the named files: `waitress-serve --listen=127.0.0.1:5000 app:app`. - Add a scheduled encrypted off-host backup using this procedure: Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Monitor health, disk space, failed jobs and backup age. Stop the service to test an alert; rehearse recovery with outbound effects disabled and record recovery time. Rotate any exposed credentials and require reconciliation before resuming queues. - Trap: Product mode is additional engineering, not a switch that makes a local prototype production-ready. Done when: An unauthenticated visitor cannot read private records, download private files or mutate the admin surface. A viewer cannot mutate data by making a direct request, and guessed ids cannot cross ownership boundaries. Stopping the service triggers the configured alert and the latest off-host backup restores the fixture in isolation. Do not build yet: Do not add new providers or vendor-scale features until the release gates are recorded. ### Out of scope (and why) - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing: retain the paid product if this capability is essential; it is outside this bounded build. - pixel-perfect proprietary PDF engine: retain the paid product if this capability is essential; it is outside this bounded build. - identity verification: retain the paid product if this capability is essential; it is outside this bounded build. - qualified trust services: retain the paid product if this capability is essential; it is outside this bounded build. - large template and integration ecosystem: retain the paid product if this capability is essential; it is outside this bounded build. ### README must contain - Exact install, configure, initialize, start, test and recovery commands for a clean folder. - The schema, fixture, acceptance results, private data locations and export format. - Every prerequisite and secret source, actual running costs and deliberately excluded capabilities. - An honest distinction between tests actually run and checks still awaiting real credentials or deployment. - Dependency documentation reviewed 2026-09-05: https://flask.palletsprojects.com/en/stable/installation/ ; https://docs.python.org/3/library/sqlite3.html ; https://flask-wtf.readthedocs.io/en/1.2.x/csrf/ ; https://docs.pylonsproject.org/projects/waitress/en/stable/usage.html ; https://pypdf.readthedocs.io/en/stable/user/installation.html. Recheck before upgrading; freeze the versions actually tested.
AGENTS.md
# Agent instructions · Smallpdf Pro indie build - Read `README.md` and `BUILD_PLAN.md` before writing code. The stack is fixed: Python 3.12+ and Flask, SQLite through Python sqlite3, Jinja HTML templates, CSS and vanilla JavaScript, Python unittest and browser acceptance fixtures, pypdf. Do not substitute. - Work one phase at a time, in order. Do not start a phase until every "Done when" item of the previous one passes. - Prefer the fewest moving parts that satisfy the step. No frameworks, services or dependencies the plan does not name. - Secrets live in `.env`, never in source or logs. Keep `.env.example` current when a variable is introduced. - Do not invent cryptography, security guarantees, APIs or compliance claims. - Add a focused test for every destructive, security-sensitive or data-loss path the plan names. - Run the project checks before declaring a phase complete, and record any deliberate shortcut in the README under "Tradeoffs". ## Known traps - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. - PDF files are complex untrusted input; file extension alone is not validation. - Do not claim text editing, OCR or compression quality from a page manipulation library. - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. - Export without an import or restore rehearsal is not verified portability.
BUILD_PLAN.md
# Build plan · Smallpdf Pro Build a private PDF merge, split and rotate workbench preserving originals. Phases are in dependency order. Each ends in a "Done when" list; treat an unticked item as a blocker, not a note. ## Phase 1 · Local foundation and data contract Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. ### Steps 1. Create and start the local application Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Files: `app.py`, `requirements.txt`, `.env.example`, `.gitignore` ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` 2. Implement storage and seed the named fixture For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Files: `schema.sql`, `db.py`, `manage.py`, `fixtures/README.md` ```sh python manage.py init python manage.py seed ``` 3. Protect the local request boundary Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. Files: `app.py`, `templates/base.html`, `test/test_foundation.py` ### Done when - [ ] The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. - [ ] Restarting preserves the seeded records or canonical files; running init again deletes nothing. - [ ] A cross-origin state-changing request to an admin route is refused. ### Watch out - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. ## Phase 2 · Bounded PDF intake Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. ### Steps 1. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Files: `features/bounded_pdf_intake.py`, `templates/bounded_pdf_intake.html` 2. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Files: `features/bounded_pdf_intake.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_bounded_pdf_intake.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] The malformed PDF fails with no output and leaves other jobs intact. - [ ] A filename containing ../ cannot write outside the private jobs directory. ### Watch out - PDF files are complex untrusted input; file extension alone is not validation. ## Phase 3 · Merge split rotate Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. ### Steps 1. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Files: `features/merge_split_rotate.py`, `templates/merge_split_rotate.html` 2. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Files: `features/merge_split_rotate.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_merge_split_rotate.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - [ ] Splitting page 0 or a page beyond the document is refused. ### Watch out - Do not claim text editing, OCR or compression quality from a page manipulation library. ## Phase 4 · Job isolation and cleanup Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. ### Steps 1. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Files: `features/job_isolation_and_cleanup.py`, `templates/job_isolation_and_cleanup.html` 2. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Files: `features/job_isolation_and_cleanup.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_job_isolation_and_cleanup.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] One owner cannot download a second owner job by guessing its id. - [ ] Expired files disappear from disk and their download returns 410 or 404. ### Watch out - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. ## Phase 5 · Portable delivery and clean-start proof Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. ### Steps 1. Write the user-facing runbook Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. Files: `README.md`, `.env.example` 2. Create and rehearse a recoverable backup Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. Files: `OPERATIONS.md`, `scripts/backup.py` 3. Reproduce the first-run experience Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Files: `README.md`, `verification.md` ```sh python -m pip install -r requirements.txt python -m unittest discover -s test ``` ### Done when - [ ] A new folder reaches the documented fixture outcome using only README instructions. - [ ] A backup restored in isolation preserves the proof data and can be opened. ### Watch out - Export without an import or restore rehearsal is not verified portability. ## Not in this build - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem ## After v1, if you want it - Extend job isolation and cleanup only after the fixture and recovery checks pass. - Before adding another integration, document its credentials, limits, cost and failure behavior with primary-source links.
.env.example
# Copy to .env and fill in. Never commit .env; this file documents it. # Required. A new private folder this application creates on first run; never serve it as static files. DATA_DIR=./data/smallpdf # Required · secret. Generate with python -c "import secrets; print(secrets.token_hex(32))" and save only in .env. SECRET_KEY=replace-with-a-random-secret # Required. Use indie for loopback-only personal work. Product mode must refuse to start until owner login and the deployment gates are configured. APP_MODE=indie # Required. The origin used for local forms and links; replace with the chosen HTTPS origin in product mode. SITE_URL=http://127.0.0.1:5000
PRODUCT.md
# Smallpdf Pro · product brief ## Problem The core loop is buildable, but a dependable replacement becomes a real weekend or multi-day project. For Smallpdf Pro, offer common PDF transformations through a private self-hosted interface. The hard boundary is hosted convenience, broad tools, mobile apps, signatures, ocr, and high-volume processing, plus document fidelity, identity, and compliance. ## Product outcome An operated version of a private PDF merge, split and rotate workbench preserving originals, with authorized access, restore evidence and honest scope limits. ## Target user A builder who needs a maintainable product foundation, not a one-off demo. ## Required capabilities - Docker - PostgreSQL - LibreOffice headless - local or S3-compatible storage - public HTTPS for signature links ## Explicit non-goals for v1 - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing - pixel-perfect proprietary PDF engine - identity verification - qualified trust services - large template and integration ecosystem ## Success criteria - The malformed PDF fails with no output and leaves other jobs intact. - Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - One owner cannot download a second owner job by guessing its id. - A private-data authorization check passes using a second identity. - An off-host restore drill has a date, observed result and recovery time in OPERATIONS.md. - README names the excluded vendor capabilities and actual provider/hosting costs.
BRIEF.md
# Build brief · Smallpdf Pro The one-shot brief this plan expands. `BUILD_PLAN.md` (or `MILESTONES.md`) is the same sequence broken into steps and checks; where the two disagree, the plan wins. Build me a private PDF merge, split and rotate workbench preserving originals as a bounded replacement for Smallpdf Pro. Build it in phases in the order below. Do not write the whole product in one pass. Finish the current phase, run its Done when checks, fix failures, then continue. Indie mode completes Phases 1-5. Phase 6 is required before shared or public deployment. ### Stack (fixed, do not substitute) - Runtime: Python 3.12+ and Flask. A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. - Storage: SQLite through Python sqlite3. Local ownership with explicit transactions and a portable backup path. - Interface: Jinja HTML templates, CSS and vanilla JavaScript. Implement the specified screens directly with labelled controls and progressive enhancement. - Verification: Python unittest and browser acceptance fixtures. Check invariants and the actual user workflow before the next phase. - Focused libraries: pypdf. Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. ### Data model (create this before Phase 1) - jobs(id,operation,status,error,created_at) - files(id,job_id,original_name,stored_path,sha256,page_count) - outputs(id,job_id,path,sha256) - operation parameters stored as validated JSON - Use stable ids and explicit relationships; add auxiliary tables named by the phases before those phases use them. - Acceptance fixture: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. ### Prerequisites and configuration - Python 3.12 or newer and a terminal: Install Python from python.org. Open a terminal in a new empty project folder. On Windows, use py -3 where this guide says python if python is not on PATH; on macOS/Linux use python3 if needed. Create .venv and activate it before installing packages. Verify: python --version reports 3.12+ and python -c "import sqlite3" succeeds. Cost: Python is free; this local prototype requires no hosting subscription. - A current desktop browser and text editor: Use an installed Chrome, Firefox or Edge browser. Open the empty project folder in your editor; open the terminal there, not in this catalog repository. Verify: You can create a text file in the project folder and open browser developer tools. Cost: No paid service required for this local step. - Smallpdf Pro acceptance sample: Create synthetic sample data before implementation: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Save it under fixtures/ with the expected results in fixtures/README.md; use no real credentials or customer records. Verify: The fixture files and expected outcomes exist and can be inspected without a vendor account. Cost: No paid service required for this local step. - Confirm the bounded replacement: The deliverable is a private PDF merge, split and rotate workbench preserving originals. Read every exclusion below. Indie mode runs locally; any public or shared use requires the product access and deployment gates first. Verify: You can name the primary workflow and the vendor features this version deliberately leaves out. Cost: No paid service required for this local step. - Configuration: DATA_DIR, SECRET_KEY, APP_MODE, SITE_URL. Ship .env.example, replace placeholders and exclude secrets from git. ### Phase 1 · Local foundation and data contract Build: Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. - Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Commands, after creating the named files: `python -m venv .venv`; `python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf`; `python -m pip freeze > requirements.txt`; `python -m flask --app app run --host 127.0.0.1`. - For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Commands, after creating the named files: `python manage.py init`; `python manage.py seed`. - Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. - Trap: The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. Done when: The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. Restarting preserves the seeded records or canonical files; running init again deletes nothing. A cross-origin state-changing request to an admin route is refused. Do not build yet: Do not start bounded pdf intake until these checks pass. ### Phase 2 · Bounded PDF intake Build: Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. - Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: PDF files are complex untrusted input; file extension alone is not validation. Done when: The malformed PDF fails with no output and leaves other jobs intact. A filename containing ../ cannot write outside the private jobs directory. Do not build yet: Do not start merge split rotate until these checks pass. ### Phase 3 · Merge split rotate Build: Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. - Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Do not claim text editing, OCR or compression quality from a page manipulation library. Done when: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Splitting page 0 or a page beyond the document is refused. Do not build yet: Do not start job isolation and cleanup until these checks pass. ### Phase 4 · Job isolation and cleanup Build: Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. - Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. - Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Commands, after creating the named files: `python -m unittest discover -s test`. - Trap: Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. Done when: One owner cannot download a second owner job by guessing its id. Expired files disappear from disk and their download returns 410 or 404. Do not build yet: Do not start portable delivery and clean-start proof until these checks pass. ### Phase 5 · Portable delivery and clean-start proof Build: Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. - Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. - Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. - Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Commands, after creating the named files: `python -m pip install -r requirements.txt`; `python -m unittest discover -s test`. - Trap: Export without an import or restore rehearsal is not verified portability. Done when: A new folder reaches the documented fixture outcome using only README instructions. A backup restored in isolation preserves the proof data and can be opened. Do not build yet: Do not start operate and share with access controls until these checks pass. ### Phase 6 · Operate and share with access controls (product-builder only) Build: Product-builder only: make a private PDF merge, split and rotate workbench preserving originals operable for its stated audience before allowing remote access. - Add owner/member/viewer authorization as appropriate, password hashes through Werkzeug, expiring server-side sessions, CSRF and login rate limits. Add users, sessions and audit schema migrations plus an owner-init command prompting securely for its password. Enforce ownership on every private read/write/download and fail closed when product setup is incomplete. Existing learner or admin identities must use this same boundary. - Serve app:app with Waitress on loopback behind Caddy HTTPS. Configure trusted proxy headers narrowly, Secure/HttpOnly/SameSite cookies, upload limits, request ids and structured logs without private content. Run background jobs as a separate supervised process when the domain workflow requires them. Commands, after creating the named files: `waitress-serve --listen=127.0.0.1:5000 app:app`. - Add a scheduled encrypted off-host backup using this procedure: Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Monitor health, disk space, failed jobs and backup age. Stop the service to test an alert; rehearse recovery with outbound effects disabled and record recovery time. Rotate any exposed credentials and require reconciliation before resuming queues. - Trap: Product mode is additional engineering, not a switch that makes a local prototype production-ready. Done when: An unauthenticated visitor cannot read private records, download private files or mutate the admin surface. A viewer cannot mutate data by making a direct request, and guessed ids cannot cross ownership boundaries. Stopping the service triggers the configured alert and the latest off-host backup restores the fixture in isolation. Do not build yet: Do not add new providers or vendor-scale features until the release gates are recorded. ### Out of scope (and why) - This is a private PDF merge, split and rotate workbench preserving originals; full Smallpdf Pro feature parity, vendor hosting and support are not included. - hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing: retain the paid product if this capability is essential; it is outside this bounded build. - pixel-perfect proprietary PDF engine: retain the paid product if this capability is essential; it is outside this bounded build. - identity verification: retain the paid product if this capability is essential; it is outside this bounded build. - qualified trust services: retain the paid product if this capability is essential; it is outside this bounded build. - large template and integration ecosystem: retain the paid product if this capability is essential; it is outside this bounded build. ### README must contain - Exact install, configure, initialize, start, test and recovery commands for a clean folder. - The schema, fixture, acceptance results, private data locations and export format. - Every prerequisite and secret source, actual running costs and deliberately excluded capabilities. - An honest distinction between tests actually run and checks still awaiting real credentials or deployment. - Dependency documentation reviewed 2026-09-05: https://flask.palletsprojects.com/en/stable/installation/ ; https://docs.python.org/3/library/sqlite3.html ; https://flask-wtf.readthedocs.io/en/1.2.x/csrf/ ; https://docs.pylonsproject.org/projects/waitress/en/stable/usage.html ; https://pypdf.readthedocs.io/en/stable/user/installation.html. Recheck before upgrading; freeze the versions actually tested.
ARCHITECTURE.md
# Architecture · Smallpdf Pro ## Stack | Part | Choice | Why | | --- | --- | --- | | Runtime | Python 3.12+ and Flask | A small local HTTP application with readable server-side handlers and no JavaScript build pipeline. | | Storage | SQLite through Python sqlite3 | Local ownership with explicit transactions and a portable backup path. | | Interface | Jinja HTML templates, CSS and vanilla JavaScript | Implement the specified screens directly with labelled controls and progressive enhancement. | | Verification | Python unittest and browser acceptance fixtures | Check invariants and the actual user workflow before the next phase. | | Focused libraries | pypdf | Use these only for the specific file, parsing or provider operations named in the phases; freeze tested versions. | ## Modules Each module has one owner concern and a documented way to replace it. | Module | Owns | How to replace it | | --- | --- | --- | | Data and identity | jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON | Keep stable ids and a versioned repository interface; migrate storage behind it with a fixture round-trip. | | Bounded PDF intake | Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. | Keep the acceptance contract: The malformed PDF fails with no output and leaves other jobs intact. Replace only this module after replaying its fixture; preserve ids and existing records. | | Merge split rotate | Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. | Keep the acceptance contract: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Replace only this module after replaying its fixture; preserve ids and existing records. | | Job isolation and cleanup | Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. | Keep the acceptance contract: One owner cannot download a second owner job by guessing its id. Replace only this module after replaying its fixture; preserve ids and existing records. | | Operations | Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. | Change host or backup destination only after an isolated restore and authorization check. | ## Configuration Every runtime setting is an environment variable documented in `.env.example`, validated at startup, with a safe local default wherever one exists. - `DATA_DIR` · required · A new private folder this application creates on first run; never serve it as static files. - `SECRET_KEY` · required, secret · Generate with python -c "import secrets; print(secrets.token_hex(32))" and save only in .env. - `APP_MODE` · required · Use indie for loopback-only personal work. Product mode must refuse to start until owner login and the deployment gates are configured. - `SITE_URL` · required · The origin used for local forms and links; replace with the chosen HTTPS origin in product mode. ## Production baseline - Security: least privilege, input validation at every boundary, secret redaction in logs, rate limits on abuse-prone paths, no invented security primitives. - Data: explicit schema and migrations, transactional writes where integrity matters, backup and restore procedures that have been exercised. - Integrations: adapters around third-party providers, idempotent webhook or job processing, bounded retries, timeouts. - Observability: structured logs with request or operation ids, an error-tracking hook, and health and readiness checks where a server exists. - Quality: unit tests for domain rules, integration tests at module boundaries, one end-to-end test of the critical path. ## Decision records For each dependency in the stack table, keep a short note: why it was chosen, its failure mode, and how it is replaced. Do not add infrastructure until a requirement in `PRODUCT.md` justifies it.
AGENTS.md
# Agent instructions · Smallpdf Pro product build - Read `PRODUCT.md` and `ARCHITECTURE.md` before changing code. The stack is fixed: Python 3.12+ and Flask, SQLite through Python sqlite3, Jinja HTML templates, CSS and vanilla JavaScript, Python unittest and browser acceptance fixtures, pypdf. - Implement milestone by milestone from `MILESTONES.md`; keep each change reviewable and leave the application runnable at every commit. - Treat authentication, payments, encryption, imports, webhooks and destructive actions as high-risk boundaries when present. - Never invent cryptography or silently weaken a requirement to make a check pass. - Put every external service behind an interface with a deterministic fake for tests. - Add migrations and rollback or recovery notes for every persistent data change. - Log useful operational context without credentials, tokens, passwords or personal data. - Update documentation and run every check before completing a milestone. ## Known traps - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. - PDF files are complex untrusted input; file extension alone is not validation. - Do not claim text editing, OCR or compression quality from a page manipulation library. - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. - Export without an import or restore rehearsal is not verified portability. - Product mode is additional engineering, not a switch that makes a local prototype production-ready.
MILESTONES.md
# Delivery milestones · Smallpdf Pro Estimated effort: **multi-day** for the indie phases; the production-only milestones add the trust and operability layer. ## M1 · Local foundation and data contract Create the runnable local foundation for a private PDF merge, split and rotate workbench preserving originals, including the real schema and acceptance fixture. ### Steps 1. Create and start the local application Run the venv command first, then stop and activate it before running the remaining commands. Use your OS instructions: Windows .venv\Scripts\activate.bat in cmd, or .venv\Scripts\Activate.ps1 in PowerShell; macOS/Linux source .venv/bin/activate. Then install the listed packages. Create app.py exposing app, load .env with python-dotenv, and add a /healthz route. Freeze tested dependency versions to requirements.txt. Create .env manually from .env.example; replace SECRET_KEY before launch. Files: `app.py`, `requirements.txt`, `.env.example`, `.gitignore` ```sh python -m venv .venv python -m pip install Flask Flask-WTF python-dotenv waitress tzdata pypdf python -m pip freeze > requirements.txt python -m flask --app app run --host 127.0.0.1 ``` 2. Implement storage and seed the named fixture For database-backed state create schema.sql and db.py using this model: jobs(id,operation,status,error,created_at); files(id,job_id,original_name,stored_path,sha256,page_count); outputs(id,job_id,path,sha256); operation parameters stored as validated JSON. Add the auxiliary relationships explicitly used in later phases; use stable ids, foreign keys, parameterized values and transactions. For canonical files use atomic replacement and hashes instead. Implement python manage.py init and python manage.py seed to create only synthetic data: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Re-running init must not erase data. Files: `schema.sql`, `db.py`, `manage.py`, `fixtures/README.md` ```sh python manage.py init python manage.py seed ``` 3. Protect the local request boundary Install Flask-WTF CSRF protection for forms and same-origin fetches, validate Host and Origin against SITE_URL, bound inputs and escape output. Deliberately public intake endpoints get bounded validation and rate limits; signed provider webhooks use signature checks instead of browser CSRF tokens. All other admin routes stay local until product authentication exists. When a later phase tests viewer/member permissions, implement the users, hashed passwords, expiring server sessions and role checks in this foundation first; product mode must never use a fabricated identity from request input. Add error, empty, keyboard-focus and retry states now. Files: `app.py`, `templates/base.html`, `test/test_foundation.py` ### Done when - [ ] The documented start command serves /healthz and the initial screen at http://127.0.0.1:5000. - [ ] Restarting preserves the seeded records or canonical files; running init again deletes nothing. - [ ] A cross-origin state-changing request to an admin route is refused. ### Watch out - The Flask development server is for local development only. Loopback binding alone does not replace CSRF and origin validation. ## M2 · Bounded PDF intake Bounded PDF intake for Smallpdf Pro: Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. ### Steps 1. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Accept PDF uploads with byte/page limits and generated disk names; inspect them with pypdf in a separate bounded worker. Files: `features/bounded_pdf_intake.py`, `templates/bounded_pdf_intake.html` 2. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Store originals read-only and show page count plus an explicit unsupported/encrypted-file error. Files: `features/bounded_pdf_intake.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: The malformed PDF fails with no output and leaves other jobs intact. Then check: A filename containing ../ cannot write outside the private jobs directory. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_bounded_pdf_intake.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] The malformed PDF fails with no output and leaves other jobs intact. - [ ] A filename containing ../ cannot write outside the private jobs directory. ### Watch out - PDF files are complex untrusted input; file extension alone is not validation. ## M3 · Merge split rotate Merge split rotate for Smallpdf Pro: Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. ### Steps 1. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Implement a validated ordered page selection and rotations in multiples of 90 using pypdf; never edit originals in place. Files: `features/merge_split_rotate.py`, `templates/merge_split_rotate.html` 2. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Write output to a temporary path, reopen it to verify page count, then publish a downloadable result. Files: `features/merge_split_rotate.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. Then check: Splitting page 0 or a page beyond the document is refused. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_merge_split_rotate.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - [ ] Splitting page 0 or a page beyond the document is refused. ### Watch out - Do not claim text editing, OCR or compression quality from a page manipulation library. ## M4 · Job isolation and cleanup Job isolation and cleanup for Smallpdf Pro: Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. ### Steps 1. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Serve outputs only through authorized job ids and attach a safe download filename; keep jobs separated by owner in shared mode. Files: `features/job_isolation_and_cleanup.py`, `templates/job_isolation_and_cleanup.html` 2. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Implement explicit delete and expiry cleanup of originals and outputs; export a non-content operation receipt. Files: `features/job_isolation_and_cleanup.py` 3. Exercise the acceptance fixture Use Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Check: One owner cannot download a second owner job by guessing its id. Then check: Expired files disappear from disk and their download returns 410 or 404. Add a focused regression for the failure case under test/ using a temporary database or folder and fake external services; also perform the visible workflow in a browser. Files: `test/test_job_isolation_and_cleanup.py` ```sh python -m unittest discover -s test ``` ### Done when - [ ] One owner cannot download a second owner job by guessing its id. - [ ] Expired files disappear from disk and their download returns 410 or 404. ### Watch out - Browser preview success does not guarantee print fidelity; inspect sample outputs in an independent viewer. ## M5 · Portable delivery and clean-start proof Finish the Smallpdf Pro replacement with a documented first-run path and a recoverable export. ### Steps 1. Write the user-facing runbook Document prerequisites, every configuration variable, data locations and the three domain workflows: Bounded PDF intake; Merge split rotate; Job isolation and cleanup. Include the exclusions, actual costs and source check date 2026-09-05. Commands shown earlier that reference project files are files the builder must implement before running them. Files: `README.md`, `.env.example` 2. Create and rehearse a recoverable backup Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. Files: `OPERATIONS.md`, `scripts/backup.py` 3. Reproduce the first-run experience Use a new folder and only README instructions to reach the fixture outcome. Install from requirements.txt, initialize storage, run the tests and exercise the UI at 375px and 1280px; use keyboard-only controls and inspect browser errors. Record exactly what passed; do not mark unrun checks complete. Files: `README.md`, `verification.md` ```sh python -m pip install -r requirements.txt python -m unittest discover -s test ``` ### Done when - [ ] A new folder reaches the documented fixture outcome using only README instructions. - [ ] A backup restored in isolation preserves the proof data and can be opened. ### Watch out - Export without an import or restore rehearsal is not verified portability. ## M6 · Operate and share with access controls (production only) Product-builder only: make a private PDF merge, split and rotate workbench preserving originals operable for its stated audience before allowing remote access. ### Steps 1. Establish owner access before exposure Add owner/member/viewer authorization as appropriate, password hashes through Werkzeug, expiring server-side sessions, CSRF and login rate limits. Add users, sessions and audit schema migrations plus an owner-init command prompting securely for its password. Enforce ownership on every private read/write/download and fail closed when product setup is incomplete. Existing learner or admin identities must use this same boundary. Files: `ARCHITECTURE.md`, `OPERATIONS.md` 2. Deploy a monitored service Serve app:app with Waitress on loopback behind Caddy HTTPS. Configure trusted proxy headers narrowly, Secure/HttpOnly/SameSite cookies, upload limits, request ids and structured logs without private content. Run background jobs as a separate supervised process when the domain workflow requires them. Files: `Caddyfile`, `OPERATIONS.md` ```sh waitress-serve --listen=127.0.0.1:5000 app:app ``` 3. Rehearse loss and recovery Add a scheduled encrypted off-host backup using this procedure: Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. Monitor health, disk space, failed jobs and backup age. Stop the service to test an alert; rehearse recovery with outbound effects disabled and record recovery time. Rotate any exposed credentials and require reconciliation before resuming queues. Files: `OPERATIONS.md`, `release-checklist.md` ### Done when - [ ] An unauthenticated visitor cannot read private records, download private files or mutate the admin surface. - [ ] A viewer cannot mutate data by making a direct request, and guessed ids cannot cross ownership boundaries. - [ ] Stopping the service triggers the configured alert and the latest off-host backup restores the fixture in isolation. ### Watch out - Product mode is additional engineering, not a switch that makes a local prototype production-ready.
OPERATIONS.md
# Operations · Smallpdf Pro ## Backup Use sqlite3.Connection.backup for the database in DATA_DIR and pause writers while taking the matching attachment snapshot. Keep schema version, hashes and a manifest for smallpdf. ## Restore Restore into a separate empty directory or isolated deployment, with all outbound actions and schedules disabled. Recreate this proof: Two small PDFs with labelled pages A1/A2 and B1, a rotated page and a malformed PDF. Compare ids/counts and open the result before recording the restore date. Never test a restore over the only live copy. Do a restore drill before the first real user, and write the date here when it passes. ## Monitoring Check HTTP availability, free disk, backup age and domain failures for Bounded PDF intake, Merge split rotate, Job isolation and cleanup. Alert without logging private payloads. ## Incident checklist Pause outbound jobs and public intake as appropriate, preserve redacted diagnostics, restore an isolated verified backup, rotate affected credentials and reconcile uncertain effects before reopening. 1. Contain the issue without destroying evidence or user data. 2. Record the timeline and affected scope. 3. Rotate exposed secrets and revoke compromised sessions or credentials. 4. Restore from a verified backup when needed. 5. Document the root cause, the remediation and the regression test. ## Release gate - [ ] The malformed PDF fails with no output and leaves other jobs intact. - [ ] Merging B1 then A2 then A1 yields exactly that order in a real PDF viewer. - [ ] One owner cannot download a second owner job by guessing its id. - [ ] A private-data authorization check passes using a second identity. - [ ] An off-host restore drill has a date, observed result and recovery time in OPERATIONS.md. - [ ] README names the excluded vendor capabilities and actual provider/hosting costs. ## Launch constraint Do not market omitted Smallpdf Pro capabilities as implemented. The non-goals in `PRODUCT.md` remain user-visible limitations until they are deliberately delivered.
.env.example
# Copy to .env and fill in. Never commit .env; this file documents it. # Required. A new private folder this application creates on first run; never serve it as static files. DATA_DIR=./data/smallpdf # Required · secret. Generate with python -c "import secrets; print(secrets.token_hex(32))" and save only in .env. SECRET_KEY=replace-with-a-random-secret # Required. Use indie for loopback-only personal work. Product mode must refuse to start until owner login and the deployment gates are configured. APP_MODE=indie # Required. The origin used for local forms and links; replace with the chosen HTTPS origin in product mode. SITE_URL=http://127.0.0.1:5000
$ choose a build depth, inspect the files, then open the complete pack in your agent
People still pay for Smallpdf Pro because the visible editor is reproducible, but reliable rendering and legally defensible signature workflows are not a casual side project. The recurring cost buys format edge cases, fonts, rendering, encryption, signatures, evidence, retention, storage, backups, and legal requirements, not just the visible interface.
xhosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing
xpixel-perfect proprietary PDF engine
xidentity verification
xqualified trust services
xlarge template and integration ecosystem
share on X ↗"I just replaced Smallpdf Pro ($12/mo) with one prompt"
Don't feel like building it? These folks already made it free.
Stirling PDFThe credible self-hosted Smallpdf replacement: a large transformation toolbox, local control, and no artificial per-day rationing.open source↗no votes, no pay-to-list · just what's real
Smallpdf Pro pricing
| plan | monthly | annual (per mo) | what you get |
|---|---|---|---|
| free | $0/user | $0/user | 2 Sign.com documents/month; AI files up to 50 MB and 25–35k words; PDF downloads/tasks and mobile access have daily limits but Smallpdf does not publish the numbers |
| pro | $15/user | $12/user | Unlimited use of 30+ tools, downloads, mobile app and Sign.com Premium; AI files up to 50 MB and 100k words |
| team | $15/user | $12/user | 2–19 seats; Pro features plus centralized billing, member management and priority support; AI files up to 50 MB and 100k words |
| business | custom | — | 20+ seats; custom pricing and payment terms; dedicated support; unlimited Sign.com Premium per member |
free tier2 Sign.com documents/month; AI files up to 50 MB and 25–35k words; PDF task/download and mobile caps are daily but no numeric count is published
billingmonthly + annual; 7-day free trial requiring cancellation before expiry to avoid billing
hidden costsTeam starts at 2 paid seats and Business at 20. The free plan repeatedly says 'daily limit' without publishing the count, so the practical PDF-task ceiling cannot be stated numerically from the official page.
verified 2026-08-13 · source ↗
Vibecode Smallpdf Pro
Kinda. The core of Smallpdf Pro is buildable in a weekend with the prompt on this page, but there are real gaps: hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing, pixel-perfect proprietary PDF engine. Read the honest list above before committing.
How much does Smallpdf Pro cost?
Smallpdf Pro costs about $12/month (Pro, checked 2026-07-31), which is $144 per year.
What do I lose by replacing Smallpdf Pro?
Honestly: hosted convenience, broad tools, mobile apps, signatures, OCR, and high-volume processing; pixel-perfect proprietary PDF engine; identity verification; qualified trust services; large template and integration ecosystem. If any of those are load-bearing for you, keep paying.
Is there an open-source alternative to Smallpdf Pro?
Yes: Stirling PDF (The credible self-hosted Smallpdf replacement: a large transformation toolbox, local control, and no artificial per-day rationing.) The prompt is for when you want it exactly your way.