This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

OpenPDS is a directory of AT Protocol PDS servers with open registration. It runs on Val Town as a serverless app with two entry points: an HTTP server and a daily cron job. Data comes from mary-ext/atproto-scraping and gets enriched with health, geo-IP, version, and trust metadata.

deno task check     # Type check entry points
deno task test      # Run tests (--allow-net --allow-read --allow-import)
deno fmt            # Format all files
deno lint           # Lint all .ts files
deno task deploy    # fmt + lint + check + test + vt push (full deploy pipeline)

Do not use vt push directly — always use deno task deploy which runs quality checks first.

Runtime: Deno on Val Town. Framework: Hono. Database: Val Town SQLite. Imports: via esm.sh (not npm/node_modules).

• backend/index.http.ts — HTTP trigger. Hono app serving HTML directory (/) and JSON API (/api/servers). Runs migrations on first request.
• cron/refresh.cron.ts — Cron trigger. Daily refresh: fetch PDS list → sync to DB → fetch latest version → enrich batch of servers.

1. pds-fetcher.ts downloads state.json (~2900 PDSes)
2. Each PDS upserted to SQLite with open/closed status
3. version-checker.ts gets latest PDS version from GitHub API
4. pds-enricher.ts enriches a batch (configurable, default 20): DNS resolve → health check → describeServer → listRepos user count → geo-IP batch lookup
5. Results written back to DB via updateEnrichment()

• backend/database/ — migrations.ts (schema), queries.ts (all SQL operations, row-to-object mapping)
• backend/routes/ — pages.ts (server-rendered HTML), api.ts (JSON endpoint)
• backend/services/ — Pure async functions: pds-fetcher, pds-enricher, geo-resolver, version-checker
• shared/ — types.ts (all TypeScript interfaces), constants.ts (config values, country flag helper)
• cron/ — Scheduled job orchestration

5 boolean signals, each worth 20%: contact email, ToS, privacy policy, active users (>5), latest PDS version. Calculated in SQL via CASE expressions.

• Exports use Val Town conventions: HTTP files export app.fetch, cron files export a default async function
• SQLite accessed via https://esm.town/v/stevekrouse/sqlite
• Schema changes: create new table names (append _2, _3) rather than ALTER TABLE
• No Deno namespace in shared/ code (must work in browser context too)
• Secrets via Deno.env.get(), never hardcoded

• Database columns: snake_case. TypeScript code: camelCase. rowToServer() maps between them.
• Per-request timeouts via AbortSignal.timeout() (5s for PDS endpoints, 10s for geo batch)
• Batch operations use Promise.allSettled() for partial-failure resilience
• HTML output uses custom esc() function for XSS prevention