Imposter vs Smocker
A side-by-side comparison of two self-hosted developer tools & git options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Imposter | Smocker |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 99 · Excellent | 70 · Good |
| Category | Developer Tools & Git | Developer Tools & Git |
| License | GPL-3.0 | MIT |
| Language | Kotlin | TypeScript |
| Setup difficulty | Easy | Easy |
| Min. RAM | 256 MB | 128 MB |
| Deployment | docker, binary | docker, binary |
| GitHub stars | — | ★ 1,284 |
| First released | 2016 | 2019 |
| Replaces | WireMock | WireMock, Mockoon |
What are Imposter and Smocker?
Imposter
Imposter is a scriptable, lightweight mock server for creating mock REST, SOAP and other APIs from OpenAPI specs or simple config. It is self-hosted as a single binary or container for testing.
- Mock from OpenAPI specs
- Scriptable behavior
- REST and SOAP support
- Self-hostable
Smocker
Smocker is a lightweight HTTP mock server designed for testing, with a clean UI for defining mocks and inspecting captured requests. It is easy to run in CI environments.
- Lightweight mock server
- Web UI for mocks
- Request history inspection
- YAML mock definitions
Imposter vs Smocker: key differences
Imposter is written in Kotlin, while Smocker is built with TypeScript. Licensing differs — GPL-3.0 for Imposter versus MIT for Smocker. Smocker is the lighter option, starting around 128 MB of RAM against 256 MB for Imposter. Imposter is the more established project (first released 2016), while Smocker arrived in 2019.
Why pick each one
Choose Imposter if…
- Released under the GPL-3.0 license
- Easy to set up — beginner-friendly
- First-class Docker support for quick deployment
- Written in Kotlin
Choose Smocker if…
- Released under the MIT license
- Easy to set up — beginner-friendly
- First-class Docker support for quick deployment
- Active community (1.3k GitHub stars)
Frequently asked questions
Is Imposter or Smocker better?
Neither is universally better. Smocker has the larger community; both share a easy setup difficulty, so the decision comes down to features and licensing.
Are Imposter and Smocker free and open-source?
Yes. Imposter is licensed under GPL-3.0 and Smocker under MIT. Both can be self-hosted at no software cost.
Can I run Imposter and Smocker with Docker?
Imposter: yes. Smocker: yes.
Which is lighter on resources, Imposter or Smocker?
Smocker has the smaller minimum footprint at 128 MB of RAM, compared to about 256 MB for Imposter. Real-world usage depends on library size, user count, and enabled features.