Gatling (software)


Gatling is a load and performance testing framework based on Scala and Netty. The first stable release was published on January 13, 2012. In 2015, Gatling's founder, Stéphane Landelle, created a company, dedicated to the development of the open-source project. According to Gatling Corp's official website, Gatling was downloaded more than 20,000,000 times. In June 2016, Gatling officially presented Gatling Enterprise the commercial version which included test orchestration and team collaboration features.
The software is designed to be used as a load testing tool for analyzing and measuring the performance of a variety of services, with a focus on web applications, application programming interfaces, and microservices.
Gatling was mentioned twice in ThoughtWorks Technology Radar, in 2013 and 2014, "as a tool worth trying", with an emphasis on "the interesting premise of treating your performance tests as production code".
The latest minor release is Gatling 3.14, published on May 12, 2025.
WWW gatling.io

Company History

Gatling started as an open-source project in 2012 by Stéphane Landelle, while he was the chief technology officer of a French IT consulting firm, eBusiness Information. In 2015 a dedicated company named "Gatling Corp" to develop a commercial product for load test orchestration and collaboration. The first version of Gatling Enterprise was released in 2016.
The company is based in Bagneux, France, near Paris.
Gatling Corp is a member of Systematic Paris-Region, an Île-de-France business cluster created in 2005, devoted to complex systems and ICT. Systematic Paris-Region gathers large groups, SMEs, universities and research labs to promote digital innovation. Gatling is a member of Systematic's Open Source Working Group and was elected member of Systematic's board of directors, as a representative of SMEs, in November 2016.
The company took part in some events, like the Paris Open Source Summit, Liferay's 2016 Symposium, Java User Group 's meetings, the Paris Gatling User Group and the New York Gatling User Group.

Overview of the Project

Gatling consists of an open-source core and an enterprise orchestration and collaboration platform. The open-source performance testing tool includes:
Gatling Enterprise includes all of the open-source features and additionally:
  • Real-time and interactive reporting
  • Customized reports and sharing options
  • Multiple load generator options, from fully managed to self-hosted
  • Full CI/CD integration
  • RBAC and SSO

Terminology

Simulation: The simulation file includes the different scenarios of a test, its parametrization and the injection profiles. Technically speaking, a simulation is a Scala class. Here are examples of simulations in Java and JavaScript:
//Java
public class BasicSimulation extends Simulation //JavaScript
export default simulation;Scenario: A scenario consists of a series of requests. Each scenario within a simulation can have its own injection profile. Here is an example of a scenario:
//Java
ScenarioBuilder myFirstScenario = scenario
.exec
.get);
//JavaScript
const myScenario = scenario
.exec
.get);
setUp.during)
).protocols;

Architecture

Gatling implemented a fully new architecture for a performance testing tool, in order to be more resource efficient. It makes it possible to simulate a high number of requests per second with a single machine.

Components

Recorder

Gatling comes with an HTTP web recorder to bootstrap a simulation. The HTTP recorder can be used to directly capture browser actions or convert.har files to load test scenarios.

Domain-specific language

Gatling is provided with a simple and lightweight Domain-specific language, in which simulations and scenarios are coded. This allows users to add custom behavior through many hooks. This makes simulation scripts readable and easy to maintain.
In 2024 Gatling introduced a new DSL for JavaScript and TypeScript. The JavaScript and TypeScript SDK uses GraalVM to translate JavaScript code to Java and execute load tests on a Java virtual machine. Adding JavaScript and TypeScript support made Gatling the first polyglot load testing tool in the market.
This is an example of what Gatling's domain-specific language looks like :

val scn = scenario
.exec
.get)
.pause

Reports

At the end of each test, Gatling generates a static HTML report. Reports include:
Gatling Enterprise additionally includes:
  • Real-time results
  • Advanced response metrics
  • Load generator health metrics
  • Run trends and comparison tools

Protocols support and plugins

It officially supports the following protocols:
Gatling documentation states that it is protocol agnostic, which makes it possible to implement other protocols' support.

Plugins

Gatling comes out with official and community plugins. It integrates with:

Community plugins

Here is a non-exhaustive list of plugins created by community members:

Continuous integration

Automation with Gatling is related to its simulations' maintainability. The integration with other developer tools, especially in the DevOps lifecycle, makes it possible to create performance tests at scale, that is to say to fully automate the execution of performance testing campaigns in the software development process.

Licensing

Gatling is published under Apache License 2.0, a permissive free software license written by the Apache Software Foundation.
The source code is accessible on GitHub.

Gatling Enterprise

Gatling Enterprise is the commercial version of Gatling. It is proprietary software, distributed by Gatling Corp.