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kafka

Options

services.kafka.enable

Whether to enable Apache Kafka.

Type: boolean

Default:

false

Example:

true

Declared by:

services.kafka.package

The apacheKafka package to use.

Type: package

Default:

pkgs.apacheKafka

Declared by:

services.kafka.configFiles.log4jProperties

Kafka log4j property configuration file path

Type: absolute path

Default:

"pkgs.writeText \"log4j.properties\" cfg.log4jProperties"

Declared by:

services.kafka.configFiles.serverProperties

Kafka server.properties configuration file path. Defaults to the rendered settings.

Type: absolute path

Declared by:

services.kafka.connect.enable

Whether to enable Kafka Connect.

Type: boolean

Default:

false

Example:

true

Declared by:

services.kafka.connect.initialConnectors

List of Kafka Connect connectors to set up initially

Type: list of (open submodule of lazy attribute set of (null or boolean or signed integer or string or list of (boolean or signed integer or string)))

Default:

[ ]

Declared by:

services.kafka.connect.initialConnectors.*.config

Initial configuration for the connector

Type: attribute set

Declared by:

services.kafka.connect.initialConnectors.*.name

Name of the connector

Type: string

Declared by:

services.kafka.connect.settings

connect-standalone.properties.

Note that .properties files contain mappings from string to string. Keys with dots are NOT represented by nested attrs in these settings, but instead as quoted strings (ie. settings."broker.id", NOT settings.broker.id).

Type: open submodule of lazy attribute set of (null or boolean or signed integer or string or list of (boolean or signed integer or string))

Default:

{ }

Declared by:

services.kafka.connect.settings.“bootstrap.servers”

A list of host/port pairs to use for establishing the initial connection to the Kafka cluster.

Type: list of string

Default:

[
  "localhost:9092"
]

Declared by:

services.kafka.connect.settings.“key.converter”

The key converter to use for the connector.

Type: string

Default:

"org.apache.kafka.connect.json.JsonConverter"

Declared by:

services.kafka.connect.settings.“key.converter.schemas.enable”

Whether the key converter should include schema information in the message.

Type: boolean

Default:

true

Declared by:

services.kafka.connect.settings.listeners

List of listeners for Kafka Connect (By default Kafka Connect listens on http://localhost:8083)

Type: null or (list of string)

Default:

null

Example:

[
  "http://localhost:8080"
]

Declared by:

services.kafka.connect.settings.“offset.flush.interval.ms”

Interval at which to try committing offsets for tasks

Type: signed integer

Default:

10000

Declared by:

services.kafka.connect.settings.“offset.storage.file.filename”

The file to store connector offsets in. By storing offsets on disk, a standalone process can be stopped and started on a single node and resume where it previously left off.

Type: string

Default:

${config.env.DEVENV_STATE}/kafka/connect/connect.offsets

Declared by:

services.kafka.connect.settings.“plugin.path”

The list should consist of top level directories that include any combination of: a) directories immediately containing jars with plugins and their dependencies b) uber-jars with plugins and their dependencies c) directories immediately containing the package directory structure of classes of plugins and their dependencies Note: symlinks will be followed to discover dependencies or plugins.

Type: null or (list of (string or absolute path))

Default:

null

Declared by:

services.kafka.connect.settings.“value.converter”

The value converter to use for the connector.

Type: string

Default:

"org.apache.kafka.connect.json.JsonConverter"

Declared by:

services.kafka.connect.settings.“value.converter.schemas.enable”

Whether the value converter should include schema information in the message.

Type: boolean

Default:

true

Declared by:

services.kafka.defaultMode

Which defaults to set for the mode Kafka should run in

  • kraft (default): Run Kafka in KRaft mode, Which requires no extra configuration.
  • zookeeper: Run Kafka in Zookeeper mode, this requires more configuration.

Type: one of “zookeeper”, “kraft”

Default:

"kraft"

Declared by:

services.kafka.formatLogDirs

Whether to format log dirs in KRaft mode if all log dirs are unformatted, ie. they contain no meta.properties.

Type: boolean

Default:

true

Declared by:

services.kafka.formatLogDirsIgnoreFormatted

Whether to ignore already formatted log dirs when formatting log dirs, instead of failing. Useful when replacing or adding disks.

Type: boolean

Default:

true

Declared by:

services.kafka.jre

The JRE with which to run Kafka

Type: package

Default:

pkgs.apacheKafka.passthru.jre

Declared by:

services.kafka.jvmOptions

Extra command line options for the JVM running Kafka.

Type: list of string

Default:

[ ]

Example:

[
  "-Djava.net.preferIPv4Stack=true"
  "-Dcom.sun.management.jmxremote"
  "-Dcom.sun.management.jmxremote.local.only=true"
]

Declared by:

services.kafka.log4jProperties

Kafka log4j property configuration.

Type: strings concatenated with “\n”

Default:

''
  log4j.rootLogger=INFO, stdout


  log4j.appender.stdout=org.apache.log4j.ConsoleAppender
  log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
  log4j.appender.stdout.layout.ConversionPattern=[%d] %p %m (%c)%n
''

Declared by:

services.kafka.settings

Kafka broker configuration server.properties.

Note that .properties files contain mappings from string to string. Keys with dots are NOT represented by nested attrs in these settings, but instead as quoted strings (ie. settings."broker.id", NOT settings.broker.id).

Type: open submodule of lazy attribute set of (null or boolean or signed integer or string or list of (boolean or signed integer or string))

Default:

{ }

Declared by:

services.kafka.settings.“broker.id”

Broker ID. -1 or null to auto-allocate in zookeeper mode.

Type: null or signed integer

Default:

null

Declared by:

services.kafka.settings.listeners

Kafka Listener List. See listeners. If you change this, you should also update the readiness probe.

Type: list of string

Default:

[
  "PLAINTEXT://localhost:9092"
]

Declared by:

services.kafka.settings.“log.dirs”

Log file directories.

Type: list of absolute path

Default:

[ "${config.devenv.state + "/kafka"}/logs" ]

Declared by:

Last updated Oct 11, 2026