Check out Elm Minify!


Hello there

Given the instructions on minification in the official docs, I put together a small NPM module for just that.

The idea is to have a nicely packaged solution that can be optimized and maintained separately, instead of having people maintain their own scripts with instructions to, for example, Uglify.js.

I built this for myself, but I hope it’s something you will want to use, contribute to, etc.

I am not a very experienced developer, so guidance and instructions of any kind from more senior community-members would be much appreciated!

Let me know what you think!


This is definitely a good idea, better to have one tool that gives you the optimal uglifyjs set up out of the box than having to configure it yourself for every project.

However I think there’s an easily made oversight in the current implementation; it only does one uglifyjs pass which has both compress and mangle enabled (

It says in the elm docs that you have to do compress and then mangle in separate calls to uglfyjs for the pure_funcs optimisation to take effect:

Note 1: uglifyjs is called twice there. First to --compress and second to --mangle . This is necessary! Otherwise uglifyjs will ignore our pure_funcs flag.

But once this issue is resolved I think this would a very useful tool!


Thank you! I’d appreciate issues submitted directly on Github, so I can follow up there :slight_smile:


I tried reconfiguring the implementation to “mangle” in a separate call, but got the same output. I’m not sure if this is related to the version of Uglify.js I’m using or something else.

I definitely want to have this optimized to run fast and produce the smallest possible output while maintaining Elms runtime guarantees, so I’ll investigate further on Github!


After npm install -g elm-minify, I cd'd to a directory with an elm.js output of elm make and did elm-minify elm.js. It created a new file, elm.min.js, about half the size of the original, with a single line of minified JS, but no compression that I could see. The new file works. But I got the error below. Missing dependency?

$ elm-minify elm.js

TypeError: console.table is not a function
    at Object.<anonymous> (/usr/local/lib/node_modules/elm-minify/src/cli.js:37:9)
    at Module._compile (module.js:570:32)
    at Object.Module._extensions..js (module.js:579:10)
    at Module.load (module.js:487:32)
    at tryModuleLoad (module.js:446:12)
    at Function.Module._load (module.js:438:3)
    at Module.runMain (module.js:604:10)
    at run (bootstrap_node.js:389:7)
    at startup (bootstrap_node.js:149:9)
    at bootstrap_node.js:504:3


Thank you for feedback! I’ve polyfilled it in as of v1.0.2, which was just published!

I would really appreciate all future issues to be reported directly on github :sunny:


My bad. Will do, though there probably won’t be a next time, since it now works:

$ elm-minify elm.js
 (index)              │ SIZE (KB)  │
 INPUT (elm.js)       │ 297.158    │
 OUTPUT (elm.min.js)  │ 158.172    │


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