Configuration

Every setting is an environment variable validated before the server starts. The complete reference, grouped by runtime limits, security, storage, queue, plugins, and tracing, is in the repository's configuration guide.

Copy .env.example as a starting point. Important defaults include a 20 MiB upload limit, 40 million input pixels, 4,096 output dimensions, two concurrent image jobs, two Sharp worker threads, and a 32 MiB libvips operation cache. Smart quality defaults to an SSIM threshold of 0.98; analysis compares AVIF and WebP and adds encode work, so it costs CPU and request latency. See the README benchmark command for a local measurement. Tune concurrency against the CPU and memory limits of your container; review the benchmark methodology before changing defaults.

Secrets (API_KEYS, signing keys, storage credentials, and worker credentials) belong in your deployment secret manager.

TENANTS binds key scope markers such as tenant:acme to daily request and byte quotas, exact hostname/source-alias and operation allowlists, and presets. Empty allowlists deny access; use "*" for an explicit wildcard. Daily quota counters are process-local and reset on restart, so hard quotas require one service instance. Tenant storage keys remain namespaced across instances using the configured storage adapter.

PDF conversion is disabled by default. Enable PDF_ENABLED and start the pdf Compose profile to use the isolated Poppler worker. PDF_MAX_DPI, PDF_MAX_PAGES, PDF_MAX_PIXELS, PDF_CPU_SECONDS, and PDF_MEMORY_MB bound work per request; PDF input and PNG output bytes use MAX_UPLOAD_BYTES.