[technical exploration] js-ipfs bundle optimized #398
Description
As of today, the js-ipfs dist version is considerably large (~4MB), which is a lot of JavaScript for a module designed for the browser. It is true that we have to inject a lot of code to support things like spdy, multiple transports, crypto channels and so on, but there are things that can be avoided/optimized, namely: shims everywhere for es6->es5 transpilation.
The 'promise' is that in the future, webpack's 'tree shaking' will remove duplicate code paths by reusing dependencies, but as far as I can tell, this won't work for CommonJS modules (anytime soon or ever).
Also, supporting several API's natively, namely callbacks and promises, forces every user to require everything, even if they decide to use just one, paying the cost associated.
My intuition is that the benchmarking tests will also reveal that we can optimize js-ipfs by reducing the overhead introduced by shims and that straight ES5 code will be more optimized than ES6, we will see.
So, here are some things that we might want to reconsider meanwhile:
- expose just callbacks by default and have a module to expose a promise interface
- use a subset of JS, within the ES5 scope to reduce the shims
- use a subset of JS, that matches the instructions by WebAssembly so that js-ipfs can be vastly optimised by the JS engines (idea suggested by @jbenet and @mikolalysenko)
I'm sure there will be other things we can do too.