I just refactored my build of libhdf5 etc. to WebAssembly, and with a little extra effort I was able to compile the tools (h5ls, h5dump, h5repack, etc.) to executable Javascript CLI programs. The full hdf5 library is statically linked in each one, so they’re a little big (3+ MB each)
To try it out, if you have nodejs installed you can do
npm install hdf5-wasm-tools
and then you can use any of the tools, e.g.
npx h5dump myfile.h5
(tools also run in the bun JS runtime)