I'm not the OP but I can confirm in my own project, we found about a 10x performance gap between AssemblyScript and TypeScript. In essence, we're working on a rewrite of DNAVisualization.org[1][2], a serverless web tool for the interactive inspection of raw DNA sequences. We hoped that WASM would give us a performance boost but have been generally disappointed with both the performance and the amount of complexity involved in getting the tooling to work.

We did do a benchmark[3] and, unless we made an error (likely, given that all of us are new to WASM), found that JS was much faster for our simple algorithms. WASM had the approximate performance of our original pure Python implementation[4], so not great.

[1]: https://dnavisualization.org [2]: https://academic.oup.com/nar/article/47/W1/W20/5512090 [3]: https://github.com/Lab41/dnaviz/tree/benchmarks/benchmarks/a.... [4]: https://github.com/Lab41/squiggle