Environment Variables¶

All configuration is via environment variables. Copy .env.example to .env.

Variable	Default	Description
`API_KEYS`	hardcoded dev keys	Semicolon-separated `key:tenant_id:scope1,scope2` entries
`ENV`	(unset)	Set to `production` to enforce `API_KEYS` at startup
`DATABASE_URL`	(unset — SQLite)	PostgreSQL DSN
`REDIS_URL`	(unset — in-process)	Redis DSN
`CPU_EXECUTOR_WORKERS`	`8`	Thread pool size for CPU executor
`GPU_EXECUTOR_WORKERS`	`2`	Thread pool size for GPU executor
`OTEL_EXPORTER_OTLP_ENDPOINT`	(unset)	OTLP/gRPC endpoint for distributed tracing
`OTEL_SERVICE_NAME`	`inference-engine`	Service name in traces

API_KEYS¶

API_KEYS=key1:tenant_a:predict,read_models;key2:tenant_b:predict,read_models,admin

Format: key:tenant_id:scope1,scope2. Entries separated by ;. Scopes: predict, read_models, admin.

When unset, fallback dev keys are active (dev-key, admin-key).

Warning

Never use dev keys in production. When ENV=production, the server refuses to start if API_KEYS is not set.

DATABASE_URL¶

DATABASE_URL=postgresql://user:password@127.0.0.1:5432/inference_engine

When set → PostgresJobStore (asyncpg-backed). Schema auto-created on first run. When unset → SQLiteJobStore at app/instance/jobs.db.

Note

Use 127.0.0.1 instead of localhost on Windows to avoid IPv6 resolution issues.

REDIS_URL¶

REDIS_URL=redis://localhost:6379/0

When set → async jobs enqueued to arq; rate limits enforced across all processes. When unset → async jobs run as in-process tasks; rate limits are per-process only.

OTEL_EXPORTER_OTLP_ENDPOINT¶

OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4317

When set and opentelemetry-sdk is installed, spans are exported via OTLP/gRPC. Otherwise tracing is a no-op.