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Reference
Environment Variables

Environment Variables

Every key in ephpm.toml can be overridden by an environment variable. The mapping is mechanical — EPHPM_ prefix, double underscore (__) for nesting, uppercase the key name.

The rule 

[section] subsection.key  →  EPHPM_SECTION__SUBSECTION__KEY

Examples:

TOMLEnvironment variable
[server] listen = "0.0.0.0:9090"EPHPM_SERVER__LISTEN=0.0.0.0:9090
[server.metrics] enabled = trueEPHPM_SERVER__METRICS__ENABLED=true
[php] memory_limit = "256M"EPHPM_PHP__MEMORY_LIMIT=256M
[db.sqlite] path = "/var/lib/app.db"EPHPM_DB__SQLITE__PATH=/var/lib/app.db
[db.sqlite.replication] role = "primary"EPHPM_DB__SQLITE__REPLICATION__ROLE=primary
[kv] compression = "zstd"EPHPM_KV__COMPRESSION=zstd
[kv.redis_compat] enabled = trueEPHPM_KV__REDIS_COMPAT__ENABLED=true
[cluster] enabled = trueEPHPM_CLUSTER__ENABLED=true
[cluster.kv] data_port = 7948EPHPM_CLUSTER__KV__DATA_PORT=7948

This works because ePHPm uses figment with Env::prefixed("EPHPM_").split("__").

Precedence

Highest to lowest:

  1. CLI flags (--listen, --document-root, --config)
  2. Environment variables (EPHPM_*)
  3. TOML file (whatever --config points at, default ephpm.toml)
  4. Built-in defaults

So you can bake a ephpm.toml into a container image and override per-environment via env vars without rebuilding.

Type coercion

Values come in as strings; figment + serde coerce them:

  • bool — "true" / "false" (case-insensitive)
  • numbers — parsed as the target type (e.g. "30" → u32)
  • arrays — JSON-style: EPHPM_SERVER__INDEX_FILES='["index.php","index.html"]'
  • nested tables — usually easier to keep these in TOML; you can set them via JSON env values but it gets unwieldy

Common production overrides 

# Container with a baked-in default config, overridden per env
EPHPM_SERVER__LISTEN=0.0.0.0:8080
EPHPM_SERVER__DOCUMENT_ROOT=/var/www/app
EPHPM_DB__SQLITE__PATH=/data/app.db

# Logging
RUST_LOG=info                                       # or info,ephpm_php=debug
EPHPM_SERVER__LOGGING__LEVEL=info                   # alternative to RUST_LOG

# Cluster identity (for k8s StatefulSet pods)
EPHPM_CLUSTER__ENABLED=true
EPHPM_CLUSTER__JOIN='["ephpm-headless.default.svc.cluster.local:7946"]'
EPHPM_CLUSTER__SECRET=$GOSSIP_SECRET                 # from a Secret/SealedSecret
EPHPM_CLUSTER__NODE_ID=$HOSTNAME                     # pod name as ordinal hint

# TLS via ACME
EPHPM_SERVER__TLS__DOMAINS='["example.com"]'
EPHPM_SERVER__TLS__EMAIL=admin@example.com
EPHPM_SERVER__TLS__CACHE_DIR=/data/certs

Logging-only env var

RUST_LOG is read directly by the tracing subscriber and takes precedence over [server.logging] level / EPHPM_SERVER__LOGGING__LEVEL. Use RUST_LOG for fine-grained control:

RUST_LOG=info,ephpm_query_stats=debug,ephpm_cluster=trace

See also

ConfigurationMetrics