aer

Tools

aer

Local Apex Development and Testing

aer (Apex Execution Runtime) is an Apex interpreter and test runner. Run and test Apex code locally without deploying to Salesforce, dramatically speeding up your development workflow.

Key Features

Local Execution - Run Apex code on your machine without Salesforce deployment
Fast Testing - Execute unit tests in milliseconds instead of seconds
CI/CD Integration - Run tests in continuous integration pipelines
Standard Library - Full support for List, Map, Set, String, Date, JSON, HTTP, and more
Interactive Debugging - Set breakpoints in VS Code and inspect Apex state live

Basic Usage

# Run all tests in the SFDX source tree
aer test force-app/main/default

# Filter tests by class or method name
aer test force-app/main/default --filter AccountTest

# Execute anonymous Apex (or pipe code via stdin)
aer exec "System.debug('Hello, World');"

Interactive Debugging

Pair aer with the bundled aer Local Apex Debugger extension for VS Code to step through tests, inspect locals, and evaluate expressions without leaving your editor. Run aer test --debug force-app/main/default/classes once and the CLI will install the extension (if needed), write .vscode/launch.json for you, and open VS Code with a ready-made configuration like this:

{
  "type": "aer",
  "request": "launch",
  "name": "Debug Apex Tests",
  "aerPath": "/path/to/aer",
  "stopOnEntry": true,
  "args": [
    "force-app/main/default/classes"
  ]
}

You do not need to edit launch.json by hand; rerun aer test --debug with new flags whenever you want to regenerate the configuration.

Start a debug session from the Run and Debug view (F5) and set breakpoints anywhere in your Apex tests. See Interactive Debugging → for a full walkthrough, including attach mode and troubleshooting tips.

Packaging

# Create a package from Apex source
aer package create --output packages/app.pkg force-app/main/default

# Inspect package contents
aer package list packages/app.pkg

# Generate a package file from an installed managed package
aer package mock MyNamespace --account myorg --output packages/MyNamespace.pkg

# Load package dependencies when running locally
aer test force-app/main/default --package packages/app.pkg
aer exec --path force-app/main/default --package packages/app.pkg "System.debug(MyClass.myMethod());"

# Use a directory of packages instead of individual flags
aer test force-app/main/default --package-dir ./packages

Getting Started

Getting Started →

Docs

Docs →

Choose a plan on the pricing page.

Use Cases

Rapid Development - Test Apex logic locally without deployment delays
CI/CD Pipelines - Fast, parallel test execution in continuous integration
Learning Apex - Experiment with Apex without a Salesforce org
Code Analysis - Static analysis and validation of Apex codebases
Multi-Package Development - Test code depending on multiple managed packages

Language Support

Core Features - Classes, methods, properties, constructors, inheritance, interfaces
Collections - List, Map, Set with full method support
Control Flow - If/else, loops, try/catch/finally, switch statements
DML Operations - Insert, update, delete, undelete with Database class
SOQL - Query support with WHERE, ORDER BY, LIMIT, relationships
Declarative - Flows, validation rules, formula fields, lookup filters, sharing rules
Testing - @IsTest annotations, Test.startTest(), assert methods, HttpCalloutMock
Standard Library - String, Math, Date, Datetime, Decimal, JSON, Crypto, Pattern, HTTP, Limits, XML, Compression, DOM, Url, Approval, PageReference
DataWeave - DataWeave script execution