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# Ponder Indexer - Agent Guide

Ponder-based indexer that records Kraiken protocol activity and exposes the GraphQL API consumed by the app and automation bot.

## Responsibilities
- Track Kraiken token transfers and staking events to maintain protocol stats, hourly ring buffers, and position state.
- Serve a GraphQL endpoint at `http://localhost:42069/graphql` for downstream consumers.
- Support `BASE_SEPOLIA_LOCAL_FORK`, `BASE_SEPOLIA`, and `BASE` environments through a single TypeScript codebase.
- **Tax Rate Handling**: Import `TAX_RATE_OPTIONS` from `kraiken-lib` (synced with Stake.sol via `scripts/sync-tax-rates.mjs`). The schema stores both `taxRateIndex` (source of truth) and `taxRate` decimal (for display). Event handlers extract the index from contract events and look up the decimal value.

## Key Files
- `ponder.config.ts` - Network selection and contract bindings (update addresses after deployments).
- `ponder.schema.ts` - Stats, hourly data, and position tables.
- `src/kraiken.ts` / `src/stake.ts` - Event handlers; rely on Ponder v0.13 helpers for on-chain reads during sync.
- `.ponder/` - Local SQLite/state cache (safe to delete when schemas change).

## Development Workflow
- Primary path: `nohup ./scripts/dev.sh start &` boots Anvil, deploys contracts, and launches Ponder in watch mode.
- Docker stack: `docker-compose up -d` starts all services including PostgreSQL; bootstrap creates `.env.local` automatically.
- Focused debugging: within `services/ponder/`, run `npm install` then `PONDER_NETWORK=BASE_SEPOLIA_LOCAL_FORK npm run dev` once the stack is already online.
- For production-style runs, use `npm run build` followed by `PONDER_NETWORK=BASE npm run start` and point `DATABASE_URL` to PostgreSQL if persistence is required.

## Operational Guidelines
- Confirm handler timestamps are monotonic; large gaps (>168 hours) reset the ring buffer by design.
- Regenerate typings after schema edits by restarting Ponder; generated artifacts live in `generated/`.
- If the stack script fails during boot, check `.ponder/logs` and RPC quota usage before rerunning.

## Containerized Environment (Podman/Docker)
- **Environment Loading**: `.env.local` must be explicitly sourced in the entrypoint script before `npm run dev`. Ponder's built-in env loader may not find it in containerized environments.
- **Virtual Module Errors**: If you see `Failed to load url ponder:registry/ponder:schema/ponder:api`, check:
  1. `DATABASE_URL` is properly set and accessible
  2. kraiken-lib ABIs exist (`onchain/out/Kraiken.sol/Kraiken.json`)
  3. `./scripts/build-kraiken-lib.sh` has been run so `kraiken-lib/dist/index.js` exists
  4. `ponder-env.d.ts` is writable by the container user (chmod 666 or pre-create it)
  5. Ponder version is 0.13.8+ (earlier versions had virtual module generation bugs)
- **PostgreSQL Connection**: Requires `DATABASE_URL` env var; Ponder falls back to PGlite if not set. The entrypoint must export this before Ponder starts.
- **File Permissions**: Container runs as `node` user; ensure `ponder-env.d.ts` is writable (created with 666 permissions on host).
- **API Endpoint Requirement**: Ponder 0.13.8+ requires `src/api/index.ts` to exist, even if you only use GraphQL. Missing it causes "API endpoint file not found" errors.

## Quality Checks
- Avoid reintroducing legacy subgraph assumptions; rely solely on Ponder schema helpers.
- Keep handler logic deterministic and idempotent; reorgs trigger replays.
- Use the Ponder client helpers (`context.client`, `context.contracts`) instead of manual RPC calls where possible.
