Nimbus — Local Apex Runtime & Test Runner

Run, test, and debug Salesforce Apex locally. No org. No Docker. No JVM.

Nimbus is a local Apex runtime for Salesforce. It executes Apex classes,
triggers, Flows, SOQL, and DML on your machine — against a real embedded
PostgreSQL database — so you can run Apex tests locally without a Salesforce
org. A typical test finishes in milliseconds, which makes Apex fast enough for
tight TDD loops, agent-driven development, and CI that doesn't depend on a
scratch org pool.

🌐 testnimbus.dev ·
📖 Docs ·
🚀 Quickstart ·
💬 Slack

Why Nimbus

The Salesforce inner dev loop runs through an org. You change one line, push to a
scratch org or sandbox, wait minutes, and run your tests over the wire. Nimbus
removes the org from that loop:

⚡ Tests in milliseconds, not minutes — no deploy, no round-trip.
🗄️ Real execution, not mocks — SOQL runs as SQL against embedded
PostgreSQL, DML persists, triggers fire, Flows execute.
🔌 No org, no credentials, no Docker, no JVM — a single binary, point it at
your existing SFDX project and run. Works offline.
🤖 Built for AI agents — nimbus mcp exposes the test runner over MCP so
Claude Code, Cursor, and Copilot can iterate in write-test-fix loops.
🧪 Mutation testing for Apex — verify your tests actually catch bugs.
🧰 CI-native — JUnit and Cobertura XML drop straight into GitHub Actions,
GitLab CI, SonarQube, and Codecov.

Install

macOS / Linux

curl -fsSL https://install.testnimbus.dev | sh

Homebrew

brew install nimbus-solution/nimbus/nimbus

Windows (PowerShell)

irm https://testnimbus.dev/install.ps1 | iex

Scoop

scoop bucket add nimbus https://github.com/nimbus-solution/scoop-nimbus
scoop install nimbus

Salesforce CLI plugin

sf plugins install @nimbus-solution/nimbus-sf-plugin
sf nimbus login
sf nimbus test "*"

The plugin source lives in sf-plugin/. It installs the native
Nimbus runtime automatically, verifies the release checksum, and shares the
same Nimbus Pro login as the standalone CLI.

Quickstart

From the root of your SFDX project:

# Run every test
nimbus test "*"

# Run a class or method pattern
nimbus test "AccountServiceTest.*"

# With coverage (Cobertura XML) + JUnit XML test results for CI
nimbus test "*" --coverage-report coverage.xml --results-xml results.xml

A ready-to-copy GitHub Actions workflow lives in
examples/ — see also the CI/CD guide.

Nimbus reads your sfdx-project.json, finds your classes, triggers, and Flows,
and runs your real @isTest classes — the same ones that run on the platform.
No copying, no parallel project, no rewriting tests.

No project at hand? Clone
berlinbrew-demo — a
real-shape Salesforce DX project built to showcase Nimbus — and run
nimbus test in it.

Full guide: testnimbus.dev/quickstart

What it supports

Area	Coverage
Language	Classes, interfaces, enums, inheritance, generics, exceptions, all annotations
Data	SOQL (WHERE, ORDER BY, LIMIT, aggregates, relationships, bind vars), DML (insert/update/delete/upsert/undelete)
Automation	Before/after triggers, record-triggered Flows, autolaunched Flows, subflows, platform-event Flows
Testing	`@isTest`, `@testSetup`, `System.assert*`, `Test.startTest/stopTest`, Stub API / ApexMocks, per-test transaction isolation
Tooling	Live debugger (DAP), standalone Language Server, browser Dev UI, watch mode, mutation testing, governor-limit enforcement
CI	JUnit XML, Cobertura XML, JSON, HTML coverage
AI	MCP server (`nimbus mcp`) for Claude Code, Cursor, Copilot

Coverage expands every release — see the
changelog.

Editor support

The Nimbus Language Server is standalone, so it works beyond VS Code: VS Code,
Cursor, Windsurf, Neovim, Zed, JetBrains, Emacs, Helix. The
VS Code extension is published to both the
Microsoft Marketplace and the
Open VSX registry.

How it compares

vs scratch orgs — milliseconds vs minutes; no DevHub limits.
vs ApexMocks / fflib — a real database vs stubbed return values.
vs Apex Replay Debugger — live breakpoints vs replaying a log.

Pricing

Free for individual developers, forever. Pro and Team tiers add the daemon,
parallel execution, watch mode, the debugger, mutation testing, and CI.
Free during the public beta — see
pricing.

Links

Website — https://testnimbus.dev
Documentation — https://testnimbus.dev/docs
Quickstart — https://testnimbus.dev/quickstart
FAQ — https://testnimbus.dev/faq
Changelog — https://testnimbus.dev/changelog
Demo project — https://github.com/nimbus-solution/berlinbrew-demo
Agent skills for Apex — https://github.com/nimbus-solution/nimbus-skills

_{Nimbus is a local Apex test runner / Apex execution runtime for Salesforce
developers who want to run Apex tests locally without an org. Keywords for the
humans and the crawlers: local apex runtime, run apex tests locally, apex test
runner, salesforce apex without org, apex interpreter, local salesforce
development, apex CI without scratch org.}