Ezno, a type checker for JavaScript and optimiser for React

In plain words

Ezno is a type checker and optimizer designed for JavaScript and React codebases. It performs static analysis to catch type errors before runtime and optimizes React code for better performance. Developers working with JavaScript projects, particularly those using React, can use Ezno to improve code quality and identify potential bugs during development rather than in production.

written from the facts on this page · September 2026

From the sources

Ezno is an experimental compiler I have been working on and off for a while. In short, it is a JavaScript compiler featuring checking, correctness and performance for building full-stack (rendering on the client and server) websites . The core of Ezno is a type checker for JavaScript . Type synthesis is analysing syntax and formulating properties of terms. Comparing the information on terms and how those terms are used, a type checker can prevent errors at runtime. Ezno's type checker is built from scratch. Getting the features I wanted required a lot of different functionality and needed several new ideas that as far as I know aren't present in any system or existing checker. The checker…from kaleidawave.github.io

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