The developer-first HTTP testing tool from Nimblesite. Native CLI binaries, a VS Code extension, and a portable language server. As simple as curl for one-off requests, scales to full test suites with scripting in your language — JavaScript, Python, F#, or C#. 2026-02-27T00:00:00.000Z https://napperapi.dev/ Christian Findlay https://napperapi.dev/blog/introducing-napper/ 2026-02-27T00:00:00.000Z 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Introducing Napper, a free, open-source, CLI-first API testing tool for VS Code, Zed, and any editor. A modern alternative to Postman, Bruno, and .http files with scripting in JavaScript, Python, F#, or C#, declarative assertions, composable test suites, built-in .http file conversion, and CI/CD integration via JUnit XML.