LLM_BUSY_MODE=reject answers blocked LLM requests immediately with
LLM_BUSY_STATUS (default 503, 429 works) and Retry-After, so routers
like LiteLLM can cool down and retry instead of holding a hung
connection. The default wait mode now also sends Retry-After when
LLM_WAIT_TIMEOUT expires. Document the service account (LocalSystem
default, NT SERVICE virtual-account hardening) and the Program
Files / ProgramData install layout.
- internal/config: .env-style config file (gpu-turnstile.env next to the
exe, -config flag or GPU_TURNSTILE_CONFIG); process env overrides file.
- internal/service: Windows service via golang.org/x/sys/windows/svc —
graceful SCM stop, 'service install/remove' commands, restart-on-failure
recovery (also applies staged updates). First external dependency,
Windows-only; Linux/Docker build unaffected (go.mod stays at 1.23).
- internal/update: polls the Gitea releases API, verifies the Ed25519
signature of the downloaded binary against an embedded public key
(openssl-signed by CI), swaps it in next to the running exe, and once
the GPU lock is idle exits with code 3 so service recovery restarts
onto the new version. Dev builds and empty pubkey never update.
- CI: tag builds additionally produce gpu-turnstile.exe + .sig + .sha256
attached to a Gitea release.
- LOG_FILE env var so the service has somewhere to log.