Highlights
Parallel per-commit checks — on by default. A commit's checks (and the trivy scan) now run concurrently in a bounded pool instead of one at a time. CHECK_CONCURRENCY (default: host CPU count; 1 = serial = old behavior) caps how many run at once; checks share the host CPUs, with optional per-check cpus:/memory: hints. Measured ~2.4× faster on an 8-core host (24m → 10m for an 11-check repo).
Opt-in dependency caching (CACHE=true). A clean, monorepo-aware "golden" cache built by a prime step in an isolated container and copied into each check (never written back, so it can't be poisoned). Off by default — it only pays off for download-heavy checks; compute-bound checks (go test, bundler builds) see no gain, and the copy-in can cost at high concurrency.
Self-update timer — on by default. deploy/install.sh installs a systemd timer that pulls :latest daily and restarts poll-ci only when the image digest changed (--noautoupdate to skip). The systemd-native alternative to the compose watchtower profile.
Upgrading
Existing deployments get parallel checks automatically — no config change. To keep the old serial behavior, set CHECK_CONCURRENCY=1. See the README for the full configuration reference.