Emscripten - Emscripten is an LLVM to JavaScript compiler.
Vaadin Framework - Vaadin is a web application framework for Rich Internet Applications (RIA).
Cheerp - Enterprise-grade C/C++ compiler for Web applications. Compiles to WASM/JavaScript
CheerpJ - The complete Java runtime for modern browsers. CheerpJ is the only solution that can run any large-scale, unmodified Java applications, applets, or libraries in the browser. No downloads or plugins are required.
Tiny C Compiler - The Tiny C Compiler is an x86, x86-64 and ARM processor C compiler created by Fabrice Bellard.
OpenXava - OpenXava is a Web Java Framework for Rapid Development of Enterprise Applications.