Builder

packages/builder generates api/**/*.json from WCA Export TSV v2.

Pipeline

1. fetchExportInfo — compare export_date (skips when unchanged unless --force)
2. Download + extract TSV zip (or --from <dir>)
3. Load tables into MemoryStore and build inverted indexes
4. Emit entity JSON with paged overviews
5. Write version.json + manifest.json

CLI

bun packages/builder/src/cli.ts build \
  --out api \
  --work .work \
  [--from .work/export] \
  [--only continent,country,event] \
  [--person-shard] \
  [--force] \
  [--connections 4] \
  [--tsv-url https://.../export.tsv.zip]

Performance notes

• Bottlenecks are usually assembly/JSON CPU and small-file metadata I/O, not disk bandwidth.
• Person emission uses a concurrency pool (mapPool).
• Export download uses parallel HTTP Range chunks (--connections, default 4) with per-chunk retries. On HTTP 429 it backs off longer and honors Retry-After. Raise connections only if your origin allows it — the WCA export host rate-limits aggressive parallelism.
• Use --only during development to iterate quickly.
• Optional --person-shard writes persons/shard/{xx}/{id}.json to improve filesystem behavior on some hosts.

Tests

bun test packages/builder