Node Environment Variables

This is the consolidated reference for node environment variables used by node-core.

Prefix Configuration

The default environment variable prefix is TWIN_, so variables look like TWIN_PORT and TWIN_ENTITY_STORAGE_CONNECTOR_TYPE.

The prefix is configurable for custom node implementations:

• Set envPrefix in node options when calling run(...).
• Or pass the CLI option --env-prefix <PREFIX>.

When you change the prefix, all variables in this document use your custom prefix instead of TWIN_.

Core Runtime Variables

Variable	Possible Values	Default	Notes
TWIN_DEBUG	true, false	false	Enables engine debug mode.
TWIN_SILENT	true, false	false	Suppresses console output.
TWIN_STRICT_ENV	error, warn, ignore	error	error throws on unrecognised TWIN_* variables; warn logs a warning; ignore skips validation. Any other value is rejected at startup.
TWIN_ENV_ALLOW_LIST	Comma-separated names	None	Env var names exempt from the unknown-key check. Supports wildcard patterns with a * suffix (e.g. TWIN_MY_EXTENSION_SECRET, TWIN_MY_EXT_*).
TWIN_STORAGE_FILE_ROOT	File system path	None	Root directory for file-based state and storage.
TWIN_STATE_FILENAME	File name or path	engine-state.json (when storage root is set)	State file used by node state storage.
TWIN_TENANT_ENABLED	true, false	false	Enables tenant-scoped flow.
TWIN_SCHEMA_MIGRATION_ENABLED	true, false	true	Enables automatic schema migration at startup. Set to false to disable schema version migration.
TWIN_EXTENSIONS	Comma-separated module list	None	Extension modules to load. Supports local, npm:, and https: entries.

Bootstrap Dev Variables

These variables are only read when running the bootstrap-dev CLI command. They are not used during normal server startup.

Variable	Possible Values	Default	Notes
TWIN_FEATURES	Comma-separated list	admin-user,wallet	Features to enable during bootstrap (e.g. admin-user).
TWIN_NODE_IDENTITY	DID string	Generated	Node identity DID. Generated if not provided.
TWIN_NODE_MNEMONIC	Mnemonic string	Generated	Node identity mnemonic. Generated if not provided.
TWIN_TENANT_ID	UUID string	Generated	Default tenant ID.
TWIN_TENANT_API_KEY	String	Generated	Default tenant API key.
TWIN_ORGANIZATION_IDENTITY	DID string	Generated	Organisation identity DID. Generated if not provided.
TWIN_ORGANIZATION_MNEMONIC	Mnemonic string	Generated	Organisation identity mnemonic. Generated if not provided.
TWIN_ADMIN_USER_IDENTITY	DID string	Generated	Admin user identity DID. Only used when admin-user feature is enabled.
TWIN_ADMIN_USER_MNEMONIC	Mnemonic string	Generated	Admin user mnemonic. Only used when admin-user feature is enabled.
TWIN_ADMIN_USER_NAME	Email or string	admin@tenant (multi-tenant) or admin@node (single tenant)	Admin user name. Only used when admin-user feature is enabled.
TWIN_ADMIN_USER_PASSWORD	String	Generated	Admin user password. Only used when admin-user feature is enabled.
TWIN_ADMIN_USER_SCOPE	Comma-separated list	tenant-admin,user-admin (multi-tenant) or user-admin (single-tenant)	Admin user permission scopes. Only used when admin-user feature is enabled.

Server Variables

Variable	Possible Values	Default	Notes
TWIN_PORT	Integer	3000 (web server fallback)	API server port.
TWIN_HOST	Host name or IP	localhost (web server fallback)	API server host.
TWIN_PUBLIC_ORIGIN	URL	None	Public API origin, for example https://api.example.com:443.
TWIN_CORS_ORIGINS	Comma-separated origins	* (if not set by runtime config)	CORS allow list.
TWIN_HTTP_METHODS	Comma-separated HTTP methods	GET,POST,PUT,DELETE,OPTIONS	CORS methods.
TWIN_HTTP_ALLOWED_HEADERS	Comma-separated headers	Runtime dependent	CORS allowed headers.
TWIN_HTTP_EXPOSED_HEADERS	Comma-separated headers	Runtime dependent	CORS exposed headers.
TWIN_HTTP_BODY_LIMITS	Comma-separated name=bytes pairs	Runtime dependent	Named request body limits for REST routes, e.g. default=2097152,large=26214400. Unset keeps the 1 MiB default and the 25 MiB large built-in.

Connector and Component Selection Variables

Variable	Possible Values	Default	Notes
TWIN_ENTITY_STORAGE_CONNECTOR_TYPE	file, memory, aws-dynamodb, azure-cosmosdb, gcp-firestoredb, scylladb, mysql, mongodb, postgresql	None	Comma-separated list allowed.
TWIN_ENTITY_STORAGE_CONNECTOR_DEFAULT	Any configured entity storage type	First configured type	Default entity storage connector.
TWIN_BLOB_STORAGE_CONNECTOR_TYPE	memory, file, ipfs, aws-s3, azure-storage, gcp-storage	None	Comma-separated list allowed.
TWIN_BLOB_STORAGE_CONNECTOR_DEFAULT	Any configured blob storage type	First configured type	Default blob storage connector.
TWIN_VAULT_CONNECTOR	entity-storage, hashicorp	None	Selects vault backend.
TWIN_LOGGING_CONNECTOR	console, entity-storage, otel, file	None	Comma-separated list allowed.
TWIN_LOGGING_BATCH_SIZE	Integer	None	Logging batch size. Set to 1 to disable batching.
TWIN_LOGGING_SILENT_COMPONENTS	Comma-separated list of component class names	None	A list of components to exclude from logging.
TWIN_LOGGING_BATCH_FLUSH_INTERVAL	Integer seconds	5	Logging batch flush interval.
TWIN_LOGGING_RETAIN_FOR	Integer minutes	2880	Age-based retention window for entity-storage logging. Set to 0 to disable age-based retention.
TWIN_LOGGING_MAX_ENTRIES	Integer	10000	Count-based retention limit for entity-storage logging. Set to 0 to disable count-based retention.
TWIN_LOGGING_RETENTION_INTERVAL	Integer minutes	5	How often retention cleanup runs for entity-storage logging. Set to 0 to disable periodic cleanup.
TWIN_LOGGING_RETENTION_BATCH_SIZE	Integer	1000	Maximum entries deleted per retention cleanup batch for entity-storage logging.
TWIN_LOGGING_FILE_DIRECTORY	Directory path	None	Directory to write log files into. Required when TWIN_LOGGING_CONNECTOR includes file.
TWIN_LOGGING_FILE_FILENAME	String	app.log	Log filename. Only used when TWIN_LOGGING_CONNECTOR includes file.
TWIN_LOGGING_FILE_MAX_FILE_SIZE_BYTES	Integer bytes	10485760	Max log file size before rotation. Set to 0 to disable rotation. Only used when TWIN_LOGGING_CONNECTOR includes file.
TWIN_LOGGING_FILE_MAX_RETAINED_FILES	Integer	5	Number of rotated log files to retain. Set to 0 to keep all. Only used when TWIN_LOGGING_CONNECTOR includes file.
TWIN_EVENT_BUS_CONNECTOR	local	None	Selects event bus connector.
TWIN_EVENT_BUS_COMPONENT	service	None	Selects event bus component implementation.
TWIN_MESSAGING_EMAIL_CONNECTOR	entity-storage, aws	None	Messaging email connector type.
TWIN_MESSAGING_SMS_CONNECTOR	entity-storage, aws	None	Messaging SMS connector type.
TWIN_MESSAGING_PUSH_NOTIFICATION_CONNECTOR	entity-storage, aws	None	Messaging push connector type.
TWIN_TELEMETRY_CONNECTOR	entity-storage, open-telemetry, silent (comma-separated for multiple)	None	Telemetry connector type. When multiple values are provided, a multi-connector is created automatically as the default.
TWIN_TELEMETRY_METRICS_PRODUCERS	system, process (comma-separated)	system,process	Metrics producer types to enable.
TWIN_TELEMETRY_SILENT_COMPONENTS	Comma-separated list of component class names	None	A list of components to exclude from telemetry.
TWIN_TRACING_CONNECTOR	entity-storage, open-telemetry, silent (comma-separated for multiple)	None	Tracing connector type. When multiple values are provided, a multi-connector is created automatically as the default.
TWIN_TRACING_SILENT_COMPONENTS	Comma-separated list of component class names	None	A list of components to exclude from tracing.
TWIN_FAUCET_CONNECTOR	entity-storage, iota	None	Faucet connector type.
TWIN_WALLET_CONNECTOR	entity-storage, iota	None	Wallet connector type.
TWIN_NFT_CONNECTOR	entity-storage, iota	None	NFT connector type.
TWIN_NFT_PACKAGE_ID	String	None	Custom deployed package id for the NFT contract.
TWIN_NOTARIZATION_CONNECTOR	entity-storage, iota	None	Notarization connector type.
TWIN_IDENTITY_CONNECTOR	entity-storage, iota	None	Identity connector type.
TWIN_IDENTITY_RESOLVER_CONNECTOR	entity-storage, iota, universal	None	Identity resolver connector type.
TWIN_IDENTITY_PROFILE_CONNECTOR	entity-storage	None	Identity profile connector type.
TWIN_ATTESTATION_CONNECTOR	nft	None	Attestation connector type.
TWIN_DATA_CONVERTER_CONNECTORS	json, xml	None	Comma-separated list allowed.
TWIN_DATA_EXTRACTOR_CONNECTORS	json-path	None	Comma-separated list allowed.
TWIN_AUTOMATION_ACTION_TYPES	fetch	None	Automation action types to register.
TWIN_FEDERATED_CATALOGUE_FILTERS	filter-by-metadata	None	Federated catalogue filters.
TWIN_TRUST_GENERATORS	jwt-verifiable-credential	None	Trust generator registrations.
TWIN_TRUST_VERIFIERS	jwt-verifiable-credential	None	Trust verifier registrations.
TWIN_RIGHTS_MANAGEMENT_POLICY_ARBITERS	pass-through, default	None	Rights policy arbiter registrations.
TWIN_RIGHTS_MANAGEMENT_POLICY_ENFORCEMENT_PROCESSORS	pass-through, default	None	Rights policy enforcement processor registrations.
TWIN_RIGHTS_MANAGEMENT_POLICY_EXECUTION_ACTIONS	logging	None	Rights policy execution action registrations.
TWIN_RIGHTS_MANAGEMENT_POLICY_INFORMATION_SOURCES	identity, static, identity-profile	None	Rights policy information source registrations.
TWIN_RIGHTS_MANAGEMENT_POLICY_NEGOTIATORS	pass-through	None	Rights policy negotiator registrations.
TWIN_RIGHTS_MANAGEMENT_POLICY_OBLIGATION_ENFORCERS	pass-through	None	Rights policy obligation enforcer registrations.
TWIN_RIGHTS_MANAGEMENT_POLICY_REQUESTERS	pass-through	None	Rights policy requester registrations.

Feature Toggle and Behaviour Variables

Variable	Possible Values	Default	Notes
TWIN_ATTESTATION_VERIFICATION_METHOD_ID	Method id string	attestation-assertion	Default injected by node defaults.
TWIN_AUDITABLE_ITEM_GRAPH_ENABLED	true, false	false	Enables auditable item graph. Also enabled automatically when notarization is configured.
TWIN_AUDITABLE_ITEM_STREAM_ENABLED	true, false	false	Enables auditable item stream. Also enabled automatically when notarization is configured.
TWIN_BLOB_STORAGE_ENABLE_ENCRYPTION	true, false	false	Enables blob encryption in blob storage component flow.
TWIN_DATA_PROCESSING_ENABLED	true, false	false	Enables data processing.
TWIN_DATASPACE_ACTIVITY_LOGS_CLEANUP_INTERVAL	Integer seconds	3600	Dataspace clean-up interval.
TWIN_DATASPACE_AGREEMENT_CACHE_TTL	Integer ms	Connector default	TTL for caching dataspace agreements in the control plane service.
TWIN_DATASPACE_AGREEMENT_CACHE_MUTEX_TIMEOUT	Integer ms	Connector default	Mutex timeout for the dataspace agreement cache in the control plane service.
TWIN_DATASPACE_AGREEMENT_SWEEP_INTERVAL	Integer ms	Connector default	Interval between agreement sweep runs in the data plane service.
TWIN_DATASPACE_AGREEMENT_UNUSED_THRESHOLD	Integer ms	Connector default	Time after which an unused agreement is eligible for removal in the data plane service.
TWIN_DATASPACE_PUSH_RETRY_COUNT	Integer	Connector default	Maximum HTTP retry attempts per push delivery task execution in the data plane service.
TWIN_DATASPACE_PUSH_RETRY_BASE_DELAY	Integer ms	Connector default	Base delay for exponential backoff between push HTTP retries in the data plane service.
TWIN_DATASPACE_PUSH_SUBSCRIPTION_CLEANUP_INTERVAL	Integer ms	Connector default	Interval between orphaned push subscription cleanup scans in the data plane service.
TWIN_DATASPACE_PUSH_TIMEOUT	Integer ms	Connector default	Timeout for each push delivery HTTP POST request in the data plane service.
TWIN_DATASPACE_RETRY_COUNT	Integer	Connector default	Number of times to retry failed data plane tasks.
TWIN_DATASPACE_AUTO_START_TRANSFERS	true, false	false	Provider auto-starts transfers on request; when false the provider must call transferStarted explicitly.
TWIN_DATASPACE_CALLBACK_PATH	Path	dataspace-control-plane	Path under which the dataspace control plane is mounted; combined with the public origin to build the consumer's advertised callback address.
TWIN_DATASPACE_DATA_PLANE_PATH	Path	None	Base route path for the data plane service (mount-point prefix only, not full URL). Combined with public origin for PULL/PUSH transfers. Do not append sub-paths such as /entities or /inbox. Required for PULL or PUSH transfers.
TWIN_DATASPACE_ENABLED	true, false	false	Enables dataspace features.
TWIN_DATASPACE_RETAIN_ACTIVITY_LOGS_FOR	Integer seconds, -1	600	Dataspace activity retention period.
TWIN_DATASPACE_STALLED_NEGOTIATION_TIMEOUT	Integer seconds	30	Time before a stalled negotiation is timed out.
TWIN_DATASPACE_STALLED_TRANSFER_TIMEOUT	Integer seconds	30	Time before a stalled consumer-initiated transfer is timed out.
TWIN_DATASPACE_PROVIDER_TRANSFER_IDLE_TIMEOUT	Integer seconds	None	Idle window for provider-managed transfers before the idle policy marks the transfer as stalled.
TWIN_DATASPACE_PROVIDER_TRANSFER_POLICY_SWEEP_INTERVAL	Integer seconds	None	Sweep interval for the provider idle transfer policy.
TWIN_DOCUMENT_MANAGEMENT_ENABLED	true, false	false	Enables document management.
TWIN_FEDERATED_CATALOGUE_ENABLED	true, false	false	Enables federated catalogue features.
TWIN_FEDERATED_CATALOGUE_REMOTE_ENDPOINT	URL	None	Uses a remote federated catalogue REST client.
TWIN_FEDERATED_CATALOGUE_REST_CLIENT_PATH_PREFIX	String	catalog	Path prefix used by the REST client when forwarding requests to the remote endpoint. Only used when TWIN_FEDERATED_CATALOGUE_REMOTE_ENDPOINT is set.
TWIN_HEALTH_ENABLED	true, false	false	Enables health components.
TWIN_HEALTH_INTERVAL	Integer seconds	60	Interval between health checks.
TWIN_HEALTH_STARTUP_INTERVAL	Integer seconds	2	Initial delay before the first health check runs.
TWIN_HEALTH_APPLICATION_INTERVAL	Integer seconds	300	Interval between application health lifecycle runs (init, application, teardown).
TWIN_IDENTITY_WALLET_ADDRESS_INDEX	Integer	0	Wallet address index used by identity workflows.
TWIN_IDENTITY_DID_RESOLUTION_CACHE_TTL	Integer ms	Connector default	TTL for caching resolved DIDs. Only used when TWIN_IDENTITY_CONNECTOR=iota.
TWIN_IDENTITY_DID_RESOLUTION_CACHE_CAPACITY	Integer	Connector default	Maximum number of DID documents to hold in the resolution cache. Only used when TWIN_IDENTITY_CONNECTOR=iota and caching is enabled.
TWIN_IDENTITY_DID_RESOLUTION_CACHE_MUTEX_TIMEOUT	Integer ms	Connector default	Mutex timeout for the DID resolution cache. Only used when TWIN_IDENTITY_CONNECTOR=iota and caching is enabled.
TWIN_IDENTITY_DID_RESOLUTION_RETRIES	Integer	10	Number of times to retry resolving a DID after a write operation (create, update, or delete) to confirm propagation. Only used when TWIN_IDENTITY_CONNECTOR=iota.
TWIN_IDENTITY_DID_RESOLUTION_RETRY_DELAY	Integer ms	500	Delay between DID resolution retries after a write operation. Only used when TWIN_IDENTITY_CONNECTOR=iota.
TWIN_IMMUTABLE_PROOF_VERIFICATION_METHOD_ID	Method id string	immutable-proof-assertion	Default injected by node defaults.
TWIN_IMMUTABLE_PROOF_TASK_RETRY_COUNT	Integer	5	Number of times to retry a proof task before abandoning it. Set to 0 to disable retries.
TWIN_IMMUTABLE_PROOF_TASK_RETRY_INTERVAL	Integer seconds	5	Interval in seconds between proof task retries.
TWIN_IMMUTABLE_PROOF_TASK_FAILURE_RETAIN_FOR	Integer minutes	10080	How long to retain the record of a failed proof task. Set to -1 to retain failures forever. Default is 7 days.
TWIN_IMMUTABLE_PROOF_SWEEP_INTERVAL	Integer minutes	30	How often the immutable proof reconciliation sweep runs. Minimum 1.
TWIN_IMMUTABLE_PROOF_SWEEP_STALE_THRESHOLD	Integer minutes	180	Minimum age before a proof with no notarization is considered stale and eligible for sweep. Minimum 1.
TWIN_IMMUTABLE_PROOF_SWEEP_MAX_ATTEMPTS	Integer	5	Maximum sweep attempts before parking a proof. Minimum 1.
TWIN_IMMUTABLE_PROOF_SWEEP_BATCH_LIMIT	Integer	10	Maximum number of proofs re-enqueued per tenant per sweep cycle. Minimum 1.
TWIN_IMMUTABLE_PROOF_SWEEP_BACKOFF	Integer minutes	60	Minimum delay between sweep attempts for the same proof, with exponential backoff up to 24 hours. Minimum 1.
TWIN_IMMUTABLE_PROOF_SWEEP_ASSUME_RETRYABLE_BEFORE	ISO 8601 date or date-time	None	Proofs created before this timestamp with no interpretable task record are treated as retryable instead of parked. Date-only values are interpreted as midnight UTC.
TWIN_MESSAGING_ENABLED	true, false	false	Enables messaging components.
TWIN_RIGHTS_MANAGEMENT_CALLBACK_PATH	Path	None	Callback path used by rights management.
TWIN_TASK_SCHEDULER_ENABLED	true, false	false	Forces the task scheduler on regardless of which other features require it.
TWIN_TELEMETRY_BATCH_FLUSH_INTERVAL	Integer seconds	5	How often the telemetry connector flushes its write-ahead cache to storage. Set to 0 to disable timer-based flushing.
TWIN_TELEMETRY_BATCH_SIZE	Integer	10	Number of metric values to accumulate before flushing to storage. Set to 1 to disable size-based flushing.
TWIN_TELEMETRY_MAX_CACHE_SIZE	Integer	1000	Maximum number of metric values held in the write-ahead cache. When the limit is reached the oldest entries are evicted. Set to 0 for unlimited.
TWIN_TELEMETRY_METRIC_DEFINITION_CACHE_CAPACITY	Integer	100	Maximum number of metric definitions held in the in-memory definition cache for the entity-storage telemetry connector.
TWIN_TELEMETRY_METRIC_DEFINITION_CACHE_TTI_MS	Integer ms	3600000	Time-to-idle in milliseconds for cached metric definitions in the entity-storage telemetry connector.
TWIN_TELEMETRY_METRICS_COLLECTOR_INTERVAL	Integer seconds	60	Polling interval between metrics collection runs.
TWIN_TELEMETRY_METRICS_PRODUCER_MAX_HISTORY	Integer	1440	Maximum number of values retained per metric.
TWIN_TRUST_IDENTITIES_ALLOW	Comma-separated list	None	Allow list for trust identity verification.
TWIN_TRUST_IDENTITIES_DENY	Comma-separated list	None	Deny list for trust identity verification.
TWIN_TRUST_JWT_TTL	Integer seconds	None	Leave unset for non-expiring JWT generation.
TWIN_TRUST_VERIFICATION_METHOD_ID	Method id string	trust-assertion	Default injected by node defaults.

Hosting Variables

Variable	Possible Values	Default	Notes
TWIN_AUTH_ADMIN_PROCESSOR_TYPE	entity-storage	None	Authentication admin processor type.
TWIN_AUTH_PROCESSOR_TYPE	entity-storage	None	Authentication processor type.
TWIN_AUTH_SIGNING_KEY_ID	Vault key identifier	auth-signing	Key used for auth signing operations.
TWIN_AUTH_API_KEY_HEADER	Header name string	x-api-key	HTTP header name for the API key on requests.
TWIN_MIME_TYPE_PROCESSORS	Comma-separated processor types	None	Additional MIME processor registrations.
TWIN_ROUTE_LOGGING_INCLUDE_BODY	true, false	Uses debug value	Includes body in route logging.
TWIN_ROUTE_LOGGING_FULL_BASE64	true, false	false	Includes full base64 payloads in route logging.
TWIN_ROUTE_LOGGING_OBFUSCATE_PROPERTIES	Comma-separated property names	None	Properties to obfuscate in route logs.
TWIN_ROUTE_METRICS_EXCLUDE_PATHS	Comma-separated path prefixes	None	URL path prefixes excluded from metrics recording. Useful for suppressing health-check or scrape endpoints. Only applies when telemetry is enabled.
TWIN_ROUTE_TRACING_EXCLUDE_PATHS	Comma-separated path prefixes	None	URL path prefixes excluded from tracing. Useful for suppressing health-check or scrape endpoints. Only applies when tracing is enabled.

REST Path Overrides

The URL path for any REST component can be overridden at startup using variables in the form:

TWIN_REST_PATH_<COMPONENT>=<path>

<COMPONENT> is the UPPER_SNAKE_CASE component type name with the Component suffix removed.

Variable	Example Value	Notes
TWIN_REST_PATH_LOGGING	/my-logs	Overrides the logging component REST path.
TWIN_REST_PATH_DATASPACE_CONTROL_PLANE	/dsp-ctrl	Overrides the dataspace control plane path.
TWIN_REST_PATH_DATASPACE_DATA_PLANE	/dsp-data	Overrides the dataspace data plane path.
TWIN_REST_PATH_TENANT_ADMIN	/my-tenants	Overrides the tenant admin component path.

The pattern extends to any component that has a default REST path configured. The variable name is derived by taking the component type identifier, removing the Component suffix, converting to UPPER*SNAKE_CASE, and prepending TWIN_REST_PATH*.

Because the set of components is open-ended, these variables are validated as a prefix group. To allow custom TWIN_REST_PATH_* variables when using TWIN_ENV_ALLOW_LIST, include the wildcard entry:

TWIN_ENV_ALLOW_LIST=restPath*

Mutex Timeout Variables

Variable	Possible Values	Default	Notes
TWIN_MUTEX_TIMEOUT_DEFAULT	Integer ms	5000	Global default mutex timeout. Used when no component-specific value is set.
TWIN_AUDITABLE_ITEM_GRAPH_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the auditable item graph component.
TWIN_AUDITABLE_ITEM_STREAM_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the auditable item stream component.
TWIN_FEDERATED_CATALOGUE_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the federated catalogue component.
TWIN_DOCUMENT_MANAGEMENT_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the document management component.
TWIN_LOGGING_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the logging component.
TWIN_ENTITY_STORAGE_MUTEX_TIMEOUT	Integer ms	None	Shared mutex timeout for the memory and file entity storage connectors.
TWIN_RIGHTS_MANAGEMENT_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the rights management component.
TWIN_TELEMETRY_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the telemetry connector.
TWIN_TRACING_MUTEX_TIMEOUT	Integer ms	None	Mutex timeout for the tracing connector.

Extension Module Loading Variables

Variable	Possible Values	Default	Notes
TWIN_EXTENSIONS_MAX_SIZE_MB	Integer MB	10	Maximum HTTPS extension download size.
TWIN_EXTENSIONS_CLEAR_CACHE	true, false	false	Clears extension cache on startup.
TWIN_EXTENSIONS_CACHE_DIRECTORY	Relative or absolute path	.tmp	Root cache directory for extension modules.
TWIN_EXTENSIONS_CACHE_TTL_HOURS	Integer hours	24	HTTPS extension cache TTL.
TWIN_EXTENSIONS_FORCE_REFRESH	true, false	false	Forces extension cache refresh.

Provider and Backend Variables

Variable	Possible Values	Default	Notes
TWIN_ENTITY_STORAGE_TABLE_PREFIX	String	None	Prefix for entity-storage tables.
TWIN_BLOB_STORAGE_PREFIX	String	None	Prefix for blob paths/keys.
TWIN_BLOB_STORAGE_ENCRYPTION_KEY_ID	Vault key identifier	blob-encryption	Blob encryption key identifier.
TWIN_VAULT_PREFIX	String	None	Prefix prepended to vault entries.
TWIN_HASHICORP_VAULT_TOKEN	Token string	None	HashiCorp Vault token.
TWIN_HASHICORP_VAULT_ENDPOINT	URL	None	HashiCorp Vault endpoint.
TWIN_AWS_DYNAMODB_AUTH_MODE	credentials, pod	None	DynamoDB auth mode.
TWIN_AWS_DYNAMODB_ACCESS_KEY_ID	String	None	DynamoDB access key id.
TWIN_AWS_DYNAMODB_SECRET_ACCESS_KEY	String	None	DynamoDB secret key.
TWIN_AWS_DYNAMODB_REGION	Region string	None	DynamoDB region.
TWIN_AWS_DYNAMODB_ENDPOINT	URL	None	DynamoDB endpoint.
TWIN_AWS_DYNAMODB_CONNECTION_TIMEOUT	Integer ms	None	DynamoDB timeout.
TWIN_AZURE_COSMOSDB_ENDPOINT	URL	None	Cosmos DB endpoint.
TWIN_AZURE_COSMOSDB_KEY	String	None	Cosmos DB key.
TWIN_AZURE_COSMOSDB_DATABASE_ID	String	None	Cosmos DB database id.
TWIN_AZURE_COSMOSDB_CONTAINER_ID	String	None	Cosmos DB container id.
TWIN_GCP_FIRESTORE_PROJECT_ID	String	None	Firestore project id.
TWIN_GCP_FIRESTORE_CREDENTIALS	String or @json: file expansion	None	Firestore credentials.
TWIN_GCP_FIRESTORE_DATABASE_ID	String	None	Firestore database id.
TWIN_GCP_FIRESTORE_COLLECTION_NAME	String	None	Firestore collection name.
TWIN_GCP_FIRESTORE_ENDPOINT	URL	None	Firestore API endpoint.
TWIN_SCYLLADB_HOSTS	Comma-separated hosts	None	Scylla hosts list.
TWIN_SCYLLADB_LOCAL_DATA_CENTER	String	None	Scylla local data centre.
TWIN_SCYLLADB_KEYSPACE	String	None	Scylla keyspace.
TWIN_SCYLLADB_PORT	Integer	None	Scylla port.
TWIN_SCYLLADB_POOL_CORE_CONNECTIONS_PER_HOST	Integer	1	Scylla pool: connections per local host.
TWIN_SCYLLADB_POOL_MAX_REQUESTS_PER_CONNECTION	Integer	1024	Scylla pool: maximum requests per connection.
TWIN_MY_SQL_HOST	String	None	MySQL host.
TWIN_MY_SQL_PORT	Integer	None	MySQL port.
TWIN_MY_SQL_USER	String	None	MySQL user.
TWIN_MY_SQL_PASSWORD	String	None	MySQL password.
TWIN_MY_SQL_DATABASE	String	None	MySQL database.
TWIN_MY_SQL_POOL_CONNECTION_LIMIT	Integer	10	MySQL pool: maximum connections.
TWIN_MY_SQL_POOL_MAX_IDLE	Integer	10	MySQL pool: maximum idle connections.
TWIN_MY_SQL_POOL_IDLE_TIMEOUT	Integer ms	60000	MySQL pool: milliseconds before an idle connection is removed.
TWIN_MY_SQL_POOL_ENABLE_KEEP_ALIVE	true, false	true	MySQL pool: enable TCP keep-alive.
TWIN_MY_SQL_POOL_WAIT_FOR_CONNECTIONS	true, false	true	MySQL pool: queue requests when pool is full instead of failing immediately.
TWIN_MY_SQL_POOL_QUEUE_LIMIT	Integer	0	MySQL pool: maximum queued requests. 0 means unlimited.
TWIN_MONGO_DB_HOST	String	None	MongoDB host.
TWIN_MONGO_DB_PORT	Integer	None	MongoDB port.
TWIN_MONGO_DB_USER	String	None	MongoDB user.
TWIN_MONGO_DB_PASSWORD	String	None	MongoDB password.
TWIN_MONGO_DB_DATABASE	String	None	MongoDB database.
TWIN_MONGO_DB_POOL_MAX_POOL_SIZE	Integer	100	MongoDB pool: maximum connections.
TWIN_MONGO_DB_POOL_MIN_POOL_SIZE	Integer	0	MongoDB pool: minimum connections to maintain.
TWIN_MONGO_DB_POOL_MAX_IDLE_TIME	Integer ms	None	MongoDB pool: milliseconds a connection can remain idle before removal.
TWIN_MONGO_DB_POOL_WAIT_QUEUE_TIMEOUT	Integer ms	None	MongoDB pool: milliseconds to wait for a connection before throwing.
TWIN_POSTGRE_SQL_HOST	String	None	PostgreSQL host.
TWIN_POSTGRE_SQL_PORT	Integer	None	PostgreSQL port.
TWIN_POSTGRE_SQL_USER	String	None	PostgreSQL user.
TWIN_POSTGRE_SQL_PASSWORD	String	None	PostgreSQL password.
TWIN_POSTGRE_SQL_DATABASE	String	None	PostgreSQL database.
TWIN_POSTGRE_SQL_POOL_MAX	Integer	10	PostgreSQL pool: maximum connections.
TWIN_POSTGRE_SQL_POOL_IDLE_TIMEOUT	Integer seconds	None	PostgreSQL pool: seconds a connection can remain idle before being closed.
TWIN_POSTGRE_SQL_POOL_CONNECT_TIMEOUT	Integer seconds	30	PostgreSQL pool: seconds to wait when establishing a connection.
TWIN_POSTGRE_SQL_POOL_MAX_LIFETIME	Integer seconds	None	PostgreSQL pool: maximum seconds a connection can remain open.
TWIN_IPFS_API_URL	URL	None	IPFS API URL.
TWIN_IPFS_BEARER_TOKEN	String	None	IPFS bearer token.
TWIN_AWS_S3_AUTH_MODE	credentials, pod	credentials	AWS S3 auth mode.
TWIN_AWS_S3_ACCESS_KEY_ID	String	None	AWS S3 access key id.
TWIN_AWS_S3_SECRET_ACCESS_KEY	String	None	AWS S3 secret key.
TWIN_AWS_S3_REGION	Region string	None	AWS S3 region.
TWIN_AWS_S3_BUCKET_NAME	String	None	AWS S3 bucket name.
TWIN_AWS_S3_ENDPOINT	URL	None	AWS S3 endpoint.
TWIN_AZURE_STORAGE_ACCOUNT_NAME	String	None	Azure Storage account name.
TWIN_AZURE_STORAGE_ACCOUNT_KEY	String	None	Azure Storage account key.
TWIN_AZURE_STORAGE_CONTAINER_NAME	String	None	Azure Storage container name.
TWIN_AZURE_STORAGE_ENDPOINT	URL	None	Azure Storage endpoint.
TWIN_GCP_STORAGE_PROJECT_ID	String	None	GCP Storage project id.
TWIN_GCP_STORAGE_CREDENTIALS	String or @json: file expansion	None	GCP Storage credentials.
TWIN_GCP_STORAGE_BUCKET_NAME	String	None	GCP Storage bucket name.
TWIN_GCP_STORAGE_ENDPOINT	URL	None	GCP Storage endpoint.
TWIN_AWS_SES_AUTH_MODE	credentials, pod	credentials	AWS SES auth mode.
TWIN_AWS_SES_ACCESS_KEY_ID	String	None	AWS SES access key id.
TWIN_AWS_SES_SECRET_ACCESS_KEY	String	None	AWS SES secret key.
TWIN_AWS_SES_REGION	Region string	None	AWS SES region.
TWIN_AWS_SES_ENDPOINT	URL	None	AWS SES endpoint.
TWIN_AWS_MESSAGING_PUSH_NOTIFICATION_APPLICATIONS	JSON string or @json: file expansion	None	Push notification application definitions.
TWIN_IOTA_NODE_ENDPOINT	URL	None	IOTA node endpoint.
TWIN_IOTA_FAUCET_ENDPOINT	URL	None	IOTA faucet endpoint.
TWIN_IOTA_NETWORK	Network name	None	IOTA network identifier.
TWIN_IOTA_COIN_TYPE	Integer	None	IOTA coin type.
TWIN_IOTA_EXPLORER_ENDPOINT	URL	None	IOTA explorer endpoint.
TWIN_IOTA_GAS_STATION_ENDPOINT	URL	None	IOTA gas station endpoint.
TWIN_IOTA_GAS_STATION_AUTH_TOKEN	String	None	IOTA gas station auth token.
TWIN_IOTA_GAS_BUDGET	Integer	None	IOTA gas budget, in nanos.
TWIN_IOTA_GAS_RESERVATION_DURATION	Integer	None	IOTA gas reservation duration, in seconds.
TWIN_IOTA_IDENTITY_PACKAGE_ID	String	None	Custom deployed package id for the IOTA identity contract.
TWIN_UNIVERSAL_RESOLVER_ENDPOINT	URL	None	Universal resolver endpoint.
TWIN_OPEN_TELEMETRY_METER_NAME	String	twin-node	OpenTelemetry meter name. Only used when TWIN_TELEMETRY_CONNECTOR=open-telemetry.
TWIN_OPEN_TELEMETRY_METER_VERSION	String	1.0.0	OpenTelemetry metrics specification version. Only used when TWIN_TELEMETRY_CONNECTOR=open-telemetry.
TWIN_OPEN_TELEMETRY_READER	prometheus	None	OpenTelemetry metric reader type. Only used when TWIN_TELEMETRY_CONNECTOR=open-telemetry.
TWIN_OPEN_TELEMETRY_PROMETHEUS_PORT	Integer	9464	Port for the Prometheus metrics server. Only used when reader is prometheus.
TWIN_OPEN_TELEMETRY_LOGGING_LOGGER_NAME	String	twin-logging	Logger name reported in emitted OTLP log records. Only used when TWIN_LOGGING_CONNECTOR=otel.
TWIN_OPEN_TELEMETRY_LOGGING_LOGGER_VERSION	String	1.0.0	Logger version reported in emitted OTLP log records. Only used when TWIN_LOGGING_CONNECTOR=otel.
TWIN_OPEN_TELEMETRY_LOGGING_PROMETHEUS_ENDPOINT	URL	None	OTLP HTTP endpoint to push log records to, for example http://localhost:4318/v1/logs. Required when TWIN_LOGGING_CONNECTOR=otel.
TWIN_OPEN_TELEMETRY_LOGGING_PROCESSOR	batch, simple	batch	Log record processor. Use simple for local development; batch for production. Only used when TWIN_LOGGING_CONNECTOR=otel.
TWIN_OPEN_TELEMETRY_TRACING_TRACER_NAME	String	twin-node	OpenTelemetry tracer name. Only used when TWIN_TRACING_CONNECTOR=open-telemetry.
TWIN_OPEN_TELEMETRY_TRACING_TRACER_VERSION	String	1.0.0	OpenTelemetry tracing specification version. Only used when TWIN_TRACING_CONNECTOR=open-telemetry.
TWIN_OPEN_TELEMETRY_TRACING_ENDPOINT	URL	None	OTLP HTTP endpoint to push spans to, for example http://localhost:4318/v1/traces. Required when TWIN_TRACING_CONNECTOR=open-telemetry.
TWIN_OPEN_TELEMETRY_TRACING_PROCESSOR	batch, simple	batch	Span processor. Use simple for local development; batch for production. Only used when TWIN_TRACING_CONNECTOR=open-telemetry.