What is Jikken? Jikken is an open source CLI tool for automated API testing, built in Rust!

The tool was originally developed to help validate complex data APIs used for analytics dashboards while integrating well with source control and CI/CD platforms. When troubleshooting API endpoints, I found my team either messing with gluing cURL/JQ/Diff together, or writing JavaScript in tools like Postman to accomplish essentially the same thing. My goal was a CLI tool which read small test definitions and could execute them seamlessly from both a local machine or in a CI/CD pipeline.

Jikken supports things like automatic comparing of different API endpoints (across release versions or environments), JSON filtering and variable extraction (passing variables from one call to the next), injecting data files, input data generation (fuzz testing with primitive types like ints/strings or higher level types like email addresses or names), or validating against heuristics instead of exact values (expect response values to contain these things, or have numbers within a certain range, etc).

Jikken also supports global variables and secrets, has built in mechanisms such as cookie support mimicking browser functionality, automatic test generation from openapi specs, junit test output for integrating into other tools/platforms, etc.

Originally, the tool was for me and my team to use at work. Since then I've open sourced it, and brought on some cofounders to launch Jikken as a B2B SaaS. Our goal is to maintain the tool, expand the capabilities, and to build a platform which is useful for companies.

While there are many Postman-like competitors out there, our intention is to have a happy path for both open source and paid customers. Tests are files that you own/control. The test runner tooling is entirely free and open source (written in Rust). We don't require you to make an account, nor do we collect any data or telemetry from you. You can use the tooling locally, on servers, or even with CI/CD for free.

What Jikken provides as a bootstrapped SaaS company, is a platform for metrics, monitoring, and alerts of test execution across projects and environments. If, and only if, you configure an API key in the tool, you can stream telemetry back to our platform. This allows you to view real-time dashboards of all your test runs across environments and projects, metrics around performance characteristics of your API endpoints, and setup alerts to notify you in slack/teams/etc based on criteria you define. Customers can also choose to execute tests from our platform instead of running them on their own infrastructure.

As we know not all users are comfortable with a CLI, we are working to expand our free and open source tooling to provide a GUI client that is tailored for working with our files, which runs on the same engine as the CLI tool. This will also be completely free and open source, not require making an account or streaming any telemetry to us. Privacy matters.

We are aware that there are many other tools out there and we hope to have our tools be worth the effort for people to switch. We're actively working on expanding the documentation and examples on our site. As always we'd love any feedback you can provide. Thank you!