This page includes details on the schema for your workspace environmentconfiguration file, which should always be located at.idx/dev.nix.

To learn about the Nix language, see theofficial Nix languagetutorial.

packages

Packages to install in the environment.

You can use thepkgs argument to select packages to install, for examplepkgs.python3. Note that the contents ofpkgs depends on the selectedchannel channel option.

Example:

{pkgs,...}:{channel="stable-23.11";packages=[pkgs.vim];}

You can search for available packages here:stable-23.11 orunstable.

Type: list of package

Default:[ ]

channel

nixpkgs channel to use.

This channel defines the contents of thepkgs argument.

Type: one of "stable-23.05", "stable-23.11", "stable-24.05", "stable-24.11","unstable"

Default:"stable-23.11"

env

Environment variables that are set inside the developer environment.

These are propagated to all of your shells and the preview server. Environmentvariables can be especially useful if your application requires a specific setof variables.

The value of each variable can be either a string or a list of strings. Thelatter is concatenated, interspersed with colon characters.

PATH must be a list, as it's always extended and never replaced completely.

Example:

{pkgs,...}:{env={HELLO="world";# append an entry to PATHPATH=["/some/path/bin"];};}

Type: attribute set of ((list of string) or anything)

Default:{ }

idx.extensions

Code extensions you want to install in your IDX workspace.

This is a list of fully qualified extension ids, for example${publisherId}.${extensionId}.

You can find a list of available extensions on theOpen VSX Registry and enter them in yourdev.nix fileby${publisherId}.${extensionId}.

Type: list of (non-empty string or path)

Default:[ ]

idx.previews.enable

Set this totrue to enable IDX Previews.

This feature provides a way to run and reload your apps automatically as you aredeveloping them.

Type: boolean

Default:true

Example:true

idx.previews.previews

Preview configurations.

Define the commands IDX executes in your developer environment.

Example:

{pkgs,...}:{  idx.previews={enable=true;previews={web={command=["yes"];cwd="subfolder";manager="web";env={HELLO="world";};};};};}

Type: attribute set of (submodule)

Default:{ }

idx.previews.previews.<name>.activity

Android Launch Activity

Type: string

Default:""

idx.previews.previews.<name>.command

Command to execute

Type: list of string

Default:[ ]

idx.previews.previews.<name>.cwd

Working directory

Type: string

Default:""

idx.previews.previews.<name>.env

Environment variables to set.

Type: attribute set of string

Default:{ }

idx.previews.previews.<name>.manager

Manager

Type: one of "web", "flutter", "android", "gradle"

idx.workspace.onCreate

Commands to execute when the workspace is created and opened for the first time.

This can be useful to setup the development environment. For example, here weare specifyingnpm install to run:

{pkgs,...}:{  idx.workspace.onCreate={npm-install="npm install";# files to open when the workspace is first opened.    default.openFiles=["src/index.ts"];};}

Type: attribute set of (path or string or ({ openFiles = [ string ];}))

Default:{ }

idx.workspace.onStart

Commands to execute whenever the workspace is opened.

This can be useful to start build watchers. For example, here we are specifying2 commands to run:

{pkgs,...}:{  idx.workspace.onStart={npm-watch-fe="npm run watch:frontend";npm-watch-be="npm run watch:backend";# files to open when the workspace is (re)opened.    default.openFiles=["src/index.ts"];};}

Type: attribute set of (path or string or ({ openFiles = [ string ];}))

Default:{ }

imports

You can extend your dev.nix file with an imported file.

# dev.nix{ pkgs,...}:{imports=[./some-file.nix];# ...}# some-file.nix{ pkgs,...}:{packages=[    pkgs.python3];# ...}

There are multiple reasons you may want to import a custom.nix file indev.nix:

1. Yourdev.nix file is large and you want to modularize it to improvemaintainability.

   { pkgs,...}:{channel="stable-24.11";# ...imports=[./env-cfg.nix./preview-config.nix];}

2. You want to configure options specific to your local environment and add thefile to your.gitignore list.

   # dev.nix{ pkgs, lib,...}:{# ...imports= lib.optionals(builtins.pathExists./dev.local.nix)[./dev.local.nix];}

   #.gitignore.idx/dev.local.nix

Type: list of path

Default:[ ]

services

Common services to enable when the workspace opens.

For example, to enable Postgres and use thepgvector extension, add thefollowing todev.nix:

    services.postgres={extensions=["pgvector"];enable=true;};

The following sections list all supported services and their configurableoptions.

services.docker.enable

Whether to enable Rootless docker.

Type: boolean

Default:false

Example:true

services.mongodb.enable

Whether to enable MongoDB server.

Type: boolean

Default:false

Example:true

services.mongodb.package

MongoDB package to use.

Type: package

Default:<derivation mongodb-6.0.11>

services.mongodb.port

Configures the port Mongod will listen on.

By default tcp is disabled and Mongod only listens on /tmp/mongodb/mongodb.sock.

To connect, use the connection stringmongodb://%2Ftmp%2Fmongodb%2Fmongodb.sock.

Type: 16 bit unsigned integer; between 0 and 65535 (both inclusive)

Default:0

services.mysql.enable

Whether to enable MySQL server.

The server is initialized with a passwordless user root. So to create additionalusers and create databases usemysql -u root.

Type: boolean

Default:false

Example:true

services.mysql.package

MySQL package to use.

Type: package

Default:pkgs.mysql

Example:pkgs.mysql80

services.postgres.enable

Whether to enable PostgreSQL server.

Type: boolean

Default:false

Example:true

services.postgres.enableTcp

Whether to enable Postgres to listen on TCP.

Type: boolean

Default:true

Example:true

services.postgres.package

PostgreSQL package to use.

Type: package

Default:pkgs.postgresql

Example:pkgs.postgresql_15

services.postgres.extensions

Postgres extensions to install.

Type: list of (one of "age", "apache_datasketches", "cstore_fdw", "hypopg","jsonb_deep_sum", "periods", "pg_auto_failover", "pg_bigm", "pg_cron","pg_ed25519", "pg_embedding", "pg_hint_plan", "pg_hll", "pg_ivm", "pg_net","pg_partman", "pg_rational", "pg_relusage", "pg_repack", "pg_safeupdate","pg_similarity", "pg_topn", "pg_uuidv7", "pgaudit", "pgjwt", "pgroonga","pgrouting", "pgsql-http", "pgtap", "pgvector", "plpgsql_check", "plr", "plv8","postgis", "promscale_extension", "repmgr", "rum", "smlar", "tds_fdw","temporal_tables", "timescaledb", "timescaledb-apache", "timescaledb_toolkit","tsearch_extras", "tsja", "wal2json")

Default:[ ]

Example:[ "pgvector" "postgis" ];

services.pubsub.enable

Whether to enable Google Pub/Sub emulator.

More documentation on using the emulator can be found here:https://cloud.google.com/pubsub/docs/emulator#using_the_emulator .

Type: boolean

Default:false

Example:true

services.pubsub.port

Configures the port Pub/Sub will listen on.

Type: 16 bit unsigned integer; between 0 and 65535 (both inclusive)

Default:8085

services.pubsub.project-id

Project ID to use to run the Pub/Sub emulator. This project is for testing only,it does not have to exist and is only used locally.

Type: string matching the pattern [a-z][a-z0-9-]{5,29}

Default:"idx-pubsub-emulator"

services.redis.enable

Whether to enable Redis server.

Type: boolean

Default:false

Example:true

services.redis.port

Configures the port Redis will listen on.

By default tcp is disabled and redis only listens on /tmp/redis/redis.sock.

Type: 16 bit unsigned integer; between 0 and 65535 (both inclusive)

Default:0

services.spanner.enable

Whether to enable Google Cloud Spanner Emulator.

Type: boolean

Default:false

Example:true

services.spanner.fault-injection

Whether to enable random fault injection into transactions.

Type: boolean

Default:false

Example:true

services.spanner.grpc-port

The TCP port to which the emulator should be bound.

Type: 16 bit unsigned integer; between 0 and 65535 (both inclusive)

Default:9010

services.spanner.rest-port

The port at which REST requests are served

Type: 16 bit unsigned integer; between 0 and 65535 (both inclusive)

Default:9020