Vibecode KFA Marketplace

You are building a lean indie version of KFA Marketplace.

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 =====
# KFA Marketplace indie build

## Goal

Build the smallest trustworthy replacement for the core KFA Marketplace workflow for one developer or a tiny team.

## Scope

List used keyboards with photos and condition notes, take Stripe Checkout payments, buy shipping labels for sellers, and track each board from sold to delivered.

## Quick start

1. Install the documented dependencies.
2. Copy `.env.example` to `.env`.
3. Run the development command chosen during implementation.
4. Complete the acceptance checks in `BUILD_PLAN.md`.

## Honest limits

This build deliberately does not replace:
- liquidity: buyers and sellers who are already there, which is the product
- warehouse QC: every board is inspected and its PCB tested before delivery
- buyer protection backed by that inspection instead of a seller's photos
- payout operations: KYC, earnings ledgers, and withdrawal handling
- fraud and dispute handling when a deal goes sideways

If those capabilities are essential, use Medusa instead of pretending the gap is solved.

===== AGENTS.md =====
# Agent instructions

- Optimize for a working, understandable weekend build.
- Prefer the fewest moving parts that satisfy the brief.
- Do not invent cryptography, security guarantees, APIs, or compliance claims.
- Keep secrets out of source control and logs.
- Add focused tests for destructive, security-sensitive, and data-loss paths.
- Run the project checks before declaring the build complete.
- Record any deliberate shortcut in the README under "Tradeoffs".

===== BUILD_PLAN.md =====
# Build plan

## Original build brief

Build me a small two-sided marketplace for used mechanical keyboards like KFA Marketplace, for a community I
  already have. Requirements:

- Django + SQLite, server-rendered templates with vanilla JS, no frontend framework, one process.
- Sellers post listings: board name, condition notes, up to 8 photos, a fixed price, and a shipped weight in
  pounds. Single quantity, sold means gone.
- A /moderate queue: new listings stay hidden until I approve them.
- Stripe Checkout for purchase; verify the webhook signature and mark a listing sold only when the payment
  event lands, not on redirect.
- On sale, buy a label through the EasyPost API from the seller's address and the listing weight, then email
  both sides the tracking link.
- A seller ledger: each sale credits the seller's balance minus a fee percentage from .env; a /payouts page
  shows what I owe whom, paid out by hand and recorded manually.
- Stripe and EasyPost keys in .env; Django's built-in auth for buyers and sellers, no telemetry, everything
  on my own server.
- Out of scope: escrow, buyer protection, dispute flows, and inspecting anything. Trust between strangers is
  my problem, not the app's.
- README with setup, stripe listen webhook config for local testing, and the fee math.

## Required capabilities

- Stripe account
- EasyPost account
- public HTTPS deployment
- email provider

## Delivery order

1. Scaffold the smallest runnable application and document its commands.
2. Implement the primary data model and core workflow.
3. Add validation, safe failure states, and persistence.
4. Cover the critical path with automated tests.
5. Exercise a clean install from the README and fix every missing step.

## Done when

- A new user can go from clone to first successful workflow using only the README.
- The core workflow works without paid infrastructure unless the brief requires it.
- Tests cover the highest-risk behavior.
- Known limitations are explicit rather than hidden.

===== .env.example =====
# Copy to .env and document every variable when it is introduced.
# Never put real credentials in this file.

APP_ENV=development
# Add only values required by the selected implementation.

You are building a lean indie version of KFA Marketplace.

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 =====
# KFA Marketplace indie build

## Goal

Build the smallest trustworthy replacement for the core KFA Marketplace workflow for one developer or a tiny team.

## Scope

List used keyboards with photos and condition notes, take Stripe Checkout payments, buy shipping labels for sellers, and track each board from sold to delivered.

## Quick start

1. Install the documented dependencies.
2. Copy `.env.example` to `.env`.
3. Run the development command chosen during implementation.
4. Complete the acceptance checks in `BUILD_PLAN.md`.

## Honest limits

This build deliberately does not replace:
- liquidity: buyers and sellers who are already there, which is the product
- warehouse QC: every board is inspected and its PCB tested before delivery
- buyer protection backed by that inspection instead of a seller's photos
- payout operations: KYC, earnings ledgers, and withdrawal handling
- fraud and dispute handling when a deal goes sideways

If those capabilities are essential, use Medusa instead of pretending the gap is solved.

===== AGENTS.md =====
# Agent instructions

- Optimize for a working, understandable weekend build.
- Prefer the fewest moving parts that satisfy the brief.
- Do not invent cryptography, security guarantees, APIs, or compliance claims.
- Keep secrets out of source control and logs.
- Add focused tests for destructive, security-sensitive, and data-loss paths.
- Run the project checks before declaring the build complete.
- Record any deliberate shortcut in the README under "Tradeoffs".

===== BUILD_PLAN.md =====
# Build plan

## Original build brief

Build me a small two-sided marketplace for used mechanical keyboards like KFA Marketplace, for a community I
  already have. Requirements:

- Django + SQLite, server-rendered templates with vanilla JS, no frontend framework, one process.
- Sellers post listings: board name, condition notes, up to 8 photos, a fixed price, and a shipped weight in
  pounds. Single quantity, sold means gone.
- A /moderate queue: new listings stay hidden until I approve them.
- Stripe Checkout for purchase; verify the webhook signature and mark a listing sold only when the payment
  event lands, not on redirect.
- On sale, buy a label through the EasyPost API from the seller's address and the listing weight, then email
  both sides the tracking link.
- A seller ledger: each sale credits the seller's balance minus a fee percentage from .env; a /payouts page
  shows what I owe whom, paid out by hand and recorded manually.
- Stripe and EasyPost keys in .env; Django's built-in auth for buyers and sellers, no telemetry, everything
  on my own server.
- Out of scope: escrow, buyer protection, dispute flows, and inspecting anything. Trust between strangers is
  my problem, not the app's.
- README with setup, stripe listen webhook config for local testing, and the fee math.

## Required capabilities

- Stripe account
- EasyPost account
- public HTTPS deployment
- email provider

## Delivery order

1. Scaffold the smallest runnable application and document its commands.
2. Implement the primary data model and core workflow.
3. Add validation, safe failure states, and persistence.
4. Cover the critical path with automated tests.
5. Exercise a clean install from the README and fix every missing step.

## Done when

- A new user can go from clone to first successful workflow using only the README.
- The core workflow works without paid infrastructure unless the brief requires it.
- Tests cover the highest-risk behavior.
- Known limitations are explicit rather than hidden.

===== .env.example =====
# Copy to .env and document every variable when it is introduced.
# Never put real credentials in this file.

APP_ENV=development
# Add only values required by the selected implementation.

You are building a production product version of KFA Marketplace.

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 =====
# KFA Marketplace product brief

## Problem

The software is the vibe-codeable part: listings, cart, Stripe checkout, shipping labels, seller payouts. An agent can stand all of that up in a weekend, and the consolation prompt below does. What it cannot stand up is the market. KFA is a two-sided used-keyboard exchange where every board passes through a warehouse for inspection and PCB testing before the buyer sees it, and the fee pays for that inspection and for the crowd on both sides. A clone launches empty.

## Product outcome

List used keyboards with photos and condition notes, take Stripe Checkout payments, buy shipping labels for sellers, and track each board from sold to delivered.

## Target user

A serious builder who needs a maintainable product foundation rather than a one-off demo.

## Required capabilities

- Stripe account
- EasyPost account
- public HTTPS deployment
- email provider

## Explicit non-goals for v1

- liquidity: buyers and sellers who are already there, which is the product
- warehouse QC: every board is inspected and its PCB tested before delivery
- buyer protection backed by that inspection instead of a seller's photos
- payout operations: KYC, earnings ledgers, and withdrawal handling
- fraud and dispute handling when a deal goes sideways

## Success criteria

- The primary workflow is measurable end to end.
- Setup is reproducible in a clean environment.
- Failure, recovery, and support paths are documented.
- Product claims match what the implementation actually guarantees.

===== ARCHITECTURE.md =====
# Architecture

## Starting brief

Build me a small two-sided marketplace for used mechanical keyboards like KFA Marketplace, for a community I
  already have. Requirements:

- Django + SQLite, server-rendered templates with vanilla JS, no frontend framework, one process.
- Sellers post listings: board name, condition notes, up to 8 photos, a fixed price, and a shipped weight in
  pounds. Single quantity, sold means gone.
- A /moderate queue: new listings stay hidden until I approve them.
- Stripe Checkout for purchase; verify the webhook signature and mark a listing sold only when the payment
  event lands, not on redirect.
- On sale, buy a label through the EasyPost API from the seller's address and the listing weight, then email
  both sides the tracking link.
- A seller ledger: each sale credits the seller's balance minus a fee percentage from .env; a /payouts page
  shows what I owe whom, paid out by hand and recorded manually.
- Stripe and EasyPost keys in .env; Django's built-in auth for buyers and sellers, no telemetry, everything
  on my own server.
- Out of scope: escrow, buyer protection, dispute flows, and inspecting anything. Trust between strangers is
  my problem, not the app's.
- README with setup, stripe listen webhook config for local testing, and the fee math.

## Boundaries

Separate the product into replaceable modules for interface, application logic, persistence, external integrations, and operational concerns. Keep domain logic independent from delivery frameworks and vendors.

## Production baseline

- Configuration: validated at startup with safe local defaults where possible.
- Security: least privilege, input validation, secret redaction, rate limits on abuse-prone paths, and no invented security primitives.
- Data: explicit schema and migrations, transactional writes where integrity matters, backup and restore instructions.
- Integrations: adapters around third-party providers, idempotent webhook or job processing, bounded retries, and timeouts.
- Observability: structured logs with request or operation IDs, an error-tracking hook, and health/readiness checks where a server exists.
- Quality: unit tests for domain rules, integration tests at module boundaries, and one end-to-end critical-path test.

## Decision records

For each major dependency, document why it was chosen, its failure mode, and how it can be replaced. Do not introduce infrastructure until a requirement justifies it.

===== AGENTS.md =====
# Agent instructions

- Read `PRODUCT.md` and `ARCHITECTURE.md` before changing code.
- Implement milestone by milestone; keep each change reviewable and leave the application runnable.
- 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 test pass.
- Use provider interfaces for external services and deterministic fakes in tests.
- Add migrations and rollback or recovery notes for persistent data changes.
- Log useful operational context without credentials, tokens, passwords, or personal data.
- Update documentation and run all checks before completing a milestone.

===== MILESTONES.md =====
# Delivery milestones

## M0 — Decisions and scaffold

- Confirm the runtime, persistence model, threat boundaries, and deployment target.
- Create a reproducible local environment and continuous checks.

## M1 — Core workflow

- Implement the smallest end-to-end product path with validation and tests.
- Keep integrations behind interfaces.

## M2 — Trust layer

- Add secure failure behavior, recovery paths, audit-relevant events, and data safeguards.
- Test abuse cases and destructive operations.

## M3 — Operability

- Add structured logs, error reporting hooks, health signals, backup/restore documentation, and deployment configuration.

## M4 — Release gate

- Run a clean-install test, critical-path end-to-end test, dependency review, and documented rollback exercise.
- Compare the shipped behavior with `PRODUCT.md` and publish remaining limitations.

===== OPERATIONS.md =====
# Operations

## Before release

- Validate configuration and secrets at startup.
- Define backup, restore, and rollback procedures and test them.
- Document logs, error tracking, health signals, and alert ownership.
- Set dependency update and vulnerability review expectations.

## Incident checklist

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 source when needed.
5. Document the root cause, remediation, and regression test.

## Launch constraint

Do not market omitted KFA Marketplace capabilities as implemented. The v1 non-goals in `PRODUCT.md` remain user-visible limitations until they are deliberately delivered.

# KFA Marketplace indie build

## Goal

Build the smallest trustworthy replacement for the core KFA Marketplace workflow for one developer or a tiny team.

## Scope

List used keyboards with photos and condition notes, take Stripe Checkout payments, buy shipping labels for sellers, and track each board from sold to delivered.

## Quick start

1. Install the documented dependencies.
2. Copy `.env.example` to `.env`.
3. Run the development command chosen during implementation.
4. Complete the acceptance checks in `BUILD_PLAN.md`.

## Honest limits

This build deliberately does not replace:
- liquidity: buyers and sellers who are already there, which is the product
- warehouse QC: every board is inspected and its PCB tested before delivery
- buyer protection backed by that inspection instead of a seller's photos
- payout operations: KYC, earnings ledgers, and withdrawal handling
- fraud and dispute handling when a deal goes sideways

If those capabilities are essential, use Medusa instead of pretending the gap is solved.

# Agent instructions

- Optimize for a working, understandable weekend build.
- Prefer the fewest moving parts that satisfy the brief.
- Do not invent cryptography, security guarantees, APIs, or compliance claims.
- Keep secrets out of source control and logs.
- Add focused tests for destructive, security-sensitive, and data-loss paths.
- Run the project checks before declaring the build complete.
- Record any deliberate shortcut in the README under "Tradeoffs".

# Build plan

## Original build brief

Build me a small two-sided marketplace for used mechanical keyboards like KFA Marketplace, for a community I
  already have. Requirements:

- Django + SQLite, server-rendered templates with vanilla JS, no frontend framework, one process.
- Sellers post listings: board name, condition notes, up to 8 photos, a fixed price, and a shipped weight in
  pounds. Single quantity, sold means gone.
- A /moderate queue: new listings stay hidden until I approve them.
- Stripe Checkout for purchase; verify the webhook signature and mark a listing sold only when the payment
  event lands, not on redirect.
- On sale, buy a label through the EasyPost API from the seller's address and the listing weight, then email
  both sides the tracking link.
- A seller ledger: each sale credits the seller's balance minus a fee percentage from .env; a /payouts page
  shows what I owe whom, paid out by hand and recorded manually.
- Stripe and EasyPost keys in .env; Django's built-in auth for buyers and sellers, no telemetry, everything
  on my own server.
- Out of scope: escrow, buyer protection, dispute flows, and inspecting anything. Trust between strangers is
  my problem, not the app's.
- README with setup, stripe listen webhook config for local testing, and the fee math.

## Required capabilities

- Stripe account
- EasyPost account
- public HTTPS deployment
- email provider

## Delivery order

1. Scaffold the smallest runnable application and document its commands.
2. Implement the primary data model and core workflow.
3. Add validation, safe failure states, and persistence.
4. Cover the critical path with automated tests.
5. Exercise a clean install from the README and fix every missing step.

## Done when

- A new user can go from clone to first successful workflow using only the README.
- The core workflow works without paid infrastructure unless the brief requires it.
- Tests cover the highest-risk behavior.
- Known limitations are explicit rather than hidden.

# Copy to .env and document every variable when it is introduced.
# Never put real credentials in this file.

APP_ENV=development
# Add only values required by the selected implementation.

# KFA Marketplace product brief

## Problem

The software is the vibe-codeable part: listings, cart, Stripe checkout, shipping labels, seller payouts. An agent can stand all of that up in a weekend, and the consolation prompt below does. What it cannot stand up is the market. KFA is a two-sided used-keyboard exchange where every board passes through a warehouse for inspection and PCB testing before the buyer sees it, and the fee pays for that inspection and for the crowd on both sides. A clone launches empty.

## Product outcome

List used keyboards with photos and condition notes, take Stripe Checkout payments, buy shipping labels for sellers, and track each board from sold to delivered.

## Target user

A serious builder who needs a maintainable product foundation rather than a one-off demo.

## Required capabilities

- Stripe account
- EasyPost account
- public HTTPS deployment
- email provider

## Explicit non-goals for v1

- liquidity: buyers and sellers who are already there, which is the product
- warehouse QC: every board is inspected and its PCB tested before delivery
- buyer protection backed by that inspection instead of a seller's photos
- payout operations: KYC, earnings ledgers, and withdrawal handling
- fraud and dispute handling when a deal goes sideways

## Success criteria

- The primary workflow is measurable end to end.
- Setup is reproducible in a clean environment.
- Failure, recovery, and support paths are documented.
- Product claims match what the implementation actually guarantees.

# Architecture

## Starting brief

Build me a small two-sided marketplace for used mechanical keyboards like KFA Marketplace, for a community I
  already have. Requirements:

- Django + SQLite, server-rendered templates with vanilla JS, no frontend framework, one process.
- Sellers post listings: board name, condition notes, up to 8 photos, a fixed price, and a shipped weight in
  pounds. Single quantity, sold means gone.
- A /moderate queue: new listings stay hidden until I approve them.
- Stripe Checkout for purchase; verify the webhook signature and mark a listing sold only when the payment
  event lands, not on redirect.
- On sale, buy a label through the EasyPost API from the seller's address and the listing weight, then email
  both sides the tracking link.
- A seller ledger: each sale credits the seller's balance minus a fee percentage from .env; a /payouts page
  shows what I owe whom, paid out by hand and recorded manually.
- Stripe and EasyPost keys in .env; Django's built-in auth for buyers and sellers, no telemetry, everything
  on my own server.
- Out of scope: escrow, buyer protection, dispute flows, and inspecting anything. Trust between strangers is
  my problem, not the app's.
- README with setup, stripe listen webhook config for local testing, and the fee math.

## Boundaries

Separate the product into replaceable modules for interface, application logic, persistence, external integrations, and operational concerns. Keep domain logic independent from delivery frameworks and vendors.

## Production baseline

- Configuration: validated at startup with safe local defaults where possible.
- Security: least privilege, input validation, secret redaction, rate limits on abuse-prone paths, and no invented security primitives.
- Data: explicit schema and migrations, transactional writes where integrity matters, backup and restore instructions.
- Integrations: adapters around third-party providers, idempotent webhook or job processing, bounded retries, and timeouts.
- Observability: structured logs with request or operation IDs, an error-tracking hook, and health/readiness checks where a server exists.
- Quality: unit tests for domain rules, integration tests at module boundaries, and one end-to-end critical-path test.

## Decision records

For each major dependency, document why it was chosen, its failure mode, and how it can be replaced. Do not introduce infrastructure until a requirement justifies it.

# Agent instructions

- Read `PRODUCT.md` and `ARCHITECTURE.md` before changing code.
- Implement milestone by milestone; keep each change reviewable and leave the application runnable.
- 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 test pass.
- Use provider interfaces for external services and deterministic fakes in tests.
- Add migrations and rollback or recovery notes for persistent data changes.
- Log useful operational context without credentials, tokens, passwords, or personal data.
- Update documentation and run all checks before completing a milestone.

# Delivery milestones

## M0 — Decisions and scaffold

- Confirm the runtime, persistence model, threat boundaries, and deployment target.
- Create a reproducible local environment and continuous checks.

## M1 — Core workflow

- Implement the smallest end-to-end product path with validation and tests.
- Keep integrations behind interfaces.

## M2 — Trust layer

- Add secure failure behavior, recovery paths, audit-relevant events, and data safeguards.
- Test abuse cases and destructive operations.

## M3 — Operability

- Add structured logs, error reporting hooks, health signals, backup/restore documentation, and deployment configuration.

## M4 — Release gate

- Run a clean-install test, critical-path end-to-end test, dependency review, and documented rollback exercise.
- Compare the shipped behavior with `PRODUCT.md` and publish remaining limitations.

# Operations

## Before release

- Validate configuration and secrets at startup.
- Define backup, restore, and rollback procedures and test them.
- Document logs, error tracking, health signals, and alert ownership.
- Set dependency update and vulnerability review expectations.

## Incident checklist

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 source when needed.
5. Document the root cause, remediation, and regression test.

## Launch constraint

Do not market omitted KFA Marketplace capabilities as implemented. The v1 non-goals in `PRODUCT.md` remain user-visible limitations until they are deliberately delivered.

$ choose a build depth, inspect the files, then open the complete pack in your agent