Worker running every symbol through the backtest pipeline (Backtest.background) over a historical frame window — all symbols of one Worker.run call share a single child process.
backtest: true
Discriminator for type-safe union: run the backtest pipeline
frameName: string
Timeframe bounding the run. Optional: defaults to the single registered frame; ambiguous (2+ registered) requires it
cache: boolean
Opt-in: warm the 1m candle cache over the frame window in the PARENT before forking; downloads of all Worker.run calls are serialized by a global mutex and no child starts until every queued download completes. Default: false — the cache directory is cwd-relative and children run in their own ./job directories, so enable only when candles are read from a cwd-independent source