Build your own Too Good To Go.

# Build an original app inspired by Too Good To Go

You are an experienced mobile product designer and mobile engineer. Build a working, polished MVP from the brief below. Implement the core journeys end to end; a static mockup is not sufficient. Inspect the current environment, make sensible implementation decisions, and get started. Ask a question only if a missing answer genuinely blocks implementation.

Starting platform: iOS / Android. Explicit customized Product & audience and Tech stack requirements take precedence over this starting target.

## Product & audience
Build an original native surplus-food pickup pilot called Lastplate, inspired by Too Good To Go. It is for a small approved set of stores offering their own surplus listings and test customers reserving pickup quantities. The main journey is browsing a listing, reserving available stock, and having a merchant confirm collection. Deliver iOS/Android apps and a durable authenticated service; a device-only inventory counter cannot coordinate shared reservations.

## Design
Use original food photography or licensed samples, readable pickup windows, availability labels, and a distinct reservation confirmation screen. Show a merchant’s stated contents/allergen information without promising an exact surprise assortment. Separate customer and merchant actions. Support accessibility and a list-based browse fallback when location or maps are unavailable.

## Features
1. Listings: approved merchants publish title, description, permitted images, quantity, stated pickup window, and store details. Show original test listings clearly. Authenticate merchant edits and enforce ownership; expired or withdrawn listings cannot accept new reservations.

2. Discovery: browse/filter by pickup date and area, favorite a store locally, and optionally request foreground location for distance sorting. Manual area selection must work when location is denied. Cached listings show their last refresh and never imply stock is guaranteed.

3. Reservation: submit a bounded quantity through the backend, decrement or reserve stock atomically, and return a persisted confirmation with a pickup code. Use an idempotency key so network retries cannot reserve twice. The pilot is explicitly no-payment; do not fake a charge.

4. Collection: customers show their confirmation, while authenticated merchant staff verify and mark it collected once. Enforce the supported pickup window and explain late/early handling. A client swipe alone cannot prove merchant confirmation or bypass ownership.

5. Cancellation and offline: permit cancellation under a documented rule and restore stock exactly once when appropriate. Keep cached confirmations available offline, but require a server-confirmed transition for booking/collection. Show expired, canceled, pending, unavailable, and retry states.

## Tech stack
Use Flutter/Dart native iOS/Android projects, a Go API, and PostgreSQL for a new pilot. Use existing authenticated infrastructure if available; otherwise implement a labeled local multi-client test service and provide its setup, seed data, and configuration contract. Keep secrets on the server and tokens in platform secure storage. Use SQLite for cache only, not authoritative stock. Native navigation, lifecycle recovery, and permission handling are required; do not replace the apps with mobile web pages.

## Data & behavior
User; Store; StoreMember {userId, storeId, role}; Listing {storeId, quantityAvailable, pickupStart, pickupEnd, timeZone, state}; Reservation {id, customerId, listingId, quantity, state, pickupCodeHash, idempotencyKey}; ReservationEvent; CachedListing. Use database transactions and unique constraints for stock/requests, server time for transitions, and authorization on every read/mutation. Preserve the listing/window snapshot on a reservation, audit merchant confirmation, and avoid exposing other customers’ pickup codes.

Acceptance checks and scope:
Have two test devices reserve the last unit concurrently and verify only one succeeds. Retry a request, cancel twice, confirm collection from an unauthorized store, and test an expired window. Verify offline cached confirmation, location denial, dropped responses, relaunch recovery, and both native builds. State server/device limits honestly. Exclude real payments, commercial stock imports, delivery, public merchant onboarding, guaranteed food availability, dietary safety assurances, live production operations, and copied listing content.

## Originality and assets
The named product is a reference for general workflows only. Use an original product name, visual identity, wording, layout, and assets. Do not copy proprietary code, branded logos, distinctive screens, private APIs, paid templates, or protected media. Use original or appropriately licensed sample data and assets. Build from this brief rather than scraping the reference service. Do not imply affiliation with the referenced company.

## Implementation quality
- Make every visible control work, with clear loading, success, empty, validation, and failure states. Remove controls for unimplemented features.
- Support the target platform and responsive or resizable layouts where appropriate. Use platform-appropriate accessibility semantics, labels, keyboard operation, visible focus, sufficient contrast, and reduced-motion preferences. Provide alternatives for drag-only interactions.
- Validate inputs at the relevant boundary. Treat imported or user-generated content as untrusted; render it safely. Confirm destructive actions or offer undo.
- Keep state changes reliable across navigation and reloads. Never silently lose edits. Handle persistence and network errors with an actionable message.
- Keep the scope realistic. Prioritize the complete primary journey. If a custom Features section differs from the baseline, update the data model, design, and acceptance checks to match it; explicit custom requirements take precedence over baseline assumptions.
- Provide realistic original sample content and a useful empty state. Keep sample data clearly separate from user-created data.

## Delivery and verification
1. Inspect the repository and outline the implementation in a few sentences.
2. Implement the app and connect its actual data flow. Continue until the primary journey works.
3. Run appropriate checks and test the acceptance cases above on the target platform. Verify responsive layouts and keyboard navigation when browser tools are available. For native projects, build with the available SDK and test an emulator or device when possible; report any missing native verification honestly. For games, verify the rules and gameplay loop, not only the menus.
4. Fix observed failures, then provide the runnable result, setup/run instructions, a brief explanation of what is implemented, and any specific configuration or verification limits.

This is a focused MVP. Do not add billing, AI services, or unrelated features unless explicitly requested in the brief. Start building now.