Latest from the blogJul 28, 2026devenv 2.2: attach to running processes and persistent out-of-tree environmentsRead post →

Developer Environments using Nix

Your whole development
environment, declared.

Define packages, languages, services, tasks, secrets, and tooling once. Give every developer—and CI—the same fast, reproducible environment.

Get StartedLanguages (58)Services (42)ProcessesOptions Reference

Describe your stack

Rust + PostgresPython MLNode + RedisGo + MySQLRails + React

View examplesGenerate config →

Generates a complete devenv.nix via devenv.new

devenv.nix · previewCopy

{ pkgs, ... }: {
  languages.rust.enable = true;

  services.postgres = {
    enable = true;
    initialDatabases = [{ name = "app"; }];
  };

  packages = [ pkgs.cargo-watch ];
}

<100ms

cached shell startup

100k+

prebuilt packages

58

languages

Linux · macOS · WSL

x64 · ARM64

Languages · Services · Tools

Rust

Python

Node.js

Go

Ruby

PHP

TypeScript

Elixir

Kotlin

Swift

Haskell

Scala

.NET

Lua

Erlang

OCaml

Perl

Dart

C++

Nim

Crystal

Zig

R

Julia

Rust

Python

Node.js

Go

Ruby

PHP

TypeScript

Elixir

Kotlin

Swift

Haskell

Scala

.NET

Lua

Erlang

OCaml

Perl

Dart

C++

Nim

Crystal

Zig

R

Julia

PostgreSQL

Redis

MySQL

MongoDB

MariaDB

Elasticsearch

RabbitMQ

MinIO

Caddy

nginx

ClickHouse

NATS

Meilisearch

CouchDB

InfluxDB

OpenSearch

Keycloak

Vault

Kafka

PostgreSQL

Redis

MySQL

MongoDB

MariaDB

Elasticsearch

RabbitMQ

MinIO

Caddy

nginx

ClickHouse

NATS

Meilisearch

CouchDB

InfluxDB

OpenSearch

Keycloak

Vault

Kafka

Docker

Nix

GitHub Actions

VS Code

IntelliJ

Zed

Android

WordPress

Terraform

OpenTofu

Claude Code

Linux

macOS

Docker

Nix

GitHub Actions

VS Code

IntelliJ

Zed

Android

WordPress

Terraform

OpenTofu

Claude Code

Linux

macOS

Three steps. Done.

From zero to a reproducible environment your whole team can use.

1

Install

Once Nix is installed. Works on Linux, macOS, and WSL.

$ nix profile install nixpkgs#devenv

2

Initialize & describe

Scaffold the project, then edit devenv.nix or generate it from a prompt above.

$ devenv init
$EDITOR devenv.nix

3

Activate

Everything available, in under 100ms after the first build.

$ devenv shell
(devenv) $ cargo run

Your whole stack, declared together

Languages, services, processes, tasks, secrets — all declarative.

58

Languages

Python, Rust, Go, Node, Ruby, PHP, Java, Elixir, and more — with version pinning and LSP servers.

Services

42 preconfigured services, including PostgreSQL, Redis, MySQL, RabbitMQ, MinIO, Caddy, and Elasticsearch.

services.postgres.enable = true;
services.redis.enable = true;

Processes

Declarative process management with logs, restarts, and dependencies. Just devenv up.

Tasks & git hooks

Define dependencies, run in parallel, hook into your shell or commits. Linters, formatters, codegen.

tasks."app:build" = {
  exec = "yarn build";
  before = [ "devenv:enterShell" ];
};

SecretSpec

Declarative secrets from Keychain, 1Password, LastPass, or dotenv. Keep values out of config and committed .env files.

processes.api.exec =
  "secretspec run -- npm start";

Containers

Build OCI containers from your dev environment. Same packages, same versions, same behavior.

Tests

Run integration tests with all processes active. devenv test and done.

Basics

Packages, variables, files, and scripts in native bash, zsh, fish, or nushell. Auto-activate on cd and apply updates at the next prompt.

Ad-hoc shells — zero config

Spin up a temporary environment without writing a devenv.nix. Great for experiments, scripts, and CI matrices.

$ devenv -O languages.python.enable:bool true \
       -O languages.python.version:string "3.12" \
       shell

Search packages & options

Search 100,000+ packages and every devenv option from the CLI, using the exact Nixpkgs version pinned by your project.

$ devenv search postgres
pkgs.postgresql_17
services.postgres.enable

Evaluation caching

Warm shells in milliseconds.

Auto-invalidated evaluation caching skips unchanged work. No daemons. No manual cache management. How it works.

Cached shell startup

<100ms

Cold

4832 ms

Warm

47 ms

Same config. ~100× faster on every subsequent shell.

Composability

Many environments. One shell.

Import config across folders and repositories. First-class monorepo support.

frontend/devenv.nix

languages.javascript.enable = true;

backend/devenv.nix

languages.rust.enable = true;
services.postgres.enable = true;

github:myorg/shared

services.redis.enable = true;

→

Unified environment

$ devenv shell

noderustpostgresredis

Profiles

One project. Every workflow.

Switch between frontend, backend, testing, and full-stack environments without duplicating configuration. Layer profiles manually or activate them by hostname and user.

$ devenv --profile backend shell

postgresredisAPI tools

$ devenv --profile fullstack up

backendfrontenddev server

hostname.ci-runner + user.alice

automaticdeterministic priority

devenv.nix

profiles = {
  backend.module = {
    services.postgres.enable = true;
    services.redis.enable = true;
  };

  frontend.module = {
    languages.javascript.enable = true;
    processes.dev.exec = "npm run dev";
  };

  fullstack.extends = [ "backend" "frontend" ];
};

Native process manager

One devenv up. Whole stack alive.

Built-in process supervision: dependencies, ready probes, restart policies, socket activation, automatic port allocation. Or swap in process-compose, overmind, mprocs.

postgresrunning

port :5432 · uptime 3m 12s

ready probe: pg_isready

redisrunning

port :6379 · uptime 3m 12s

restart: on-failure

migratecompleted

one-shot · exit 0

after: postgres

apirunning

port :8080 · uptime 3m 09s

after: postgres, redis, migrate

socket activation · zero-downtime restarts

Declared once in devenv.nix. Started, ordered, restarted, and stopped by the native supervisor.

SecretSpec

Declare a secret. Swap the source.

The same declaration reads from Keychain, 1Password, dotenv, or env. Load secrets at runtime without committing their values.

Keychain1PasswordLastPass.envenv

secretspec.toml

[project]
name = "my-app"

[profiles.default]
DATABASE_URL = { required = true }
STRIPE_SECRET_KEY = { required = true }

🔐Source: macOS Keychain

↓

📄secretspec.toml declares DATABASE_URL

↓

🐚$ secretspec run -- npm start — exposed only to the app

Packaging

From dev shell to deployable artifact.

Same languages, same versions, same packages. Define outputs and ship a Nix derivation.

1 · Declare

devenv.nix

languages.rust.enable = true;
outputs.app =
  config.languages.rust.import ./. {};

→

2 · Build

devenv build

$ devenv build outputs.app
• Built /nix/store/...-app
in 12.4s

→

3 · Ship

Nix store · binary cache · CI

$ nix copy --to ssh://deploy \
  /nix/store/...-app

Built in the open

Active community, frequent releases, and a growing ecosystem of services and languages.

GitHubStar & contributeRead the source, file an issue, send a PR. MIT licensed.DiscordChat with the teamGet help, share setups, follow what's coming next.BlogWhat's newRelease notes, design deep-dives, and case studies.ExamplesReady-made setupsCopy a working devenv.nix for your stack.

Start building.

Set up your first environment in minutes — or generate one from the hero above.

Get StartedView on GitHub