You get most automatically. I had a quick look at the Dockerfile of the repo. Compared to Building SWI-Prolog using Emscripten for WebAssembly (WASM), this is lacking behind a bit. As we discussed, I’d include pcre2 and remove GMP. That gives an images that is only marginally larger, has more functionality and is completely covered by permissive licenses (BSD-2, MIT, a little Apache and some non-standard permissive licenses). Only (notably) rational number arithmetic is slower.
I don’t know what version, but after updating to 3.1.37 on dev.swi-prolog.org the build failed because node.js complained about invalid opcodes. That is node.js from Ubuntu 20.04. Forgotten which version. 10? After upgrading to the latest stable, all worked fine again.