Well you conveniently skipped right over the part of my comment where I said that you shouldn't be using the whole 500kb lodash library... (also, it's disingenuous at best and borderline lying to say that lodash is 500kb. The DEVELOPER version is 500kb, the production version is 67kb before gzipping, and 22kb after gzipping)

If you are only using _.forEach, then you should only include _.forEach, which comes out to about 10kb before gzip compression, 5kb after (i just built it myself to test). And all but about 1.2kb of that is "core" code, so if you add additional lodash functions, most of them will increase the code size by about 2kb at the most.

That means that for an overhead of about 8kb, you can start adding extremely useful functions all throughout your codebase with very little overhead. 1.2kb to easily and quickly iterate over an object using the key and the value in each block;

    _.forEach(obj, function(value, key) { // do stuff })

Pure js:

    Object.keys(obj).forEach(function(key) { var value = obj[key] // do stuff })

Not that much of a difference space wise, but the performance is terrible if you are iterating over a large object, and by using Object.keys you exclude some UAs.

Now let's look at _.find in an object...

    _.find(obj, { 'age': 1}) // returns the first object (in the object) that has a property 'age' that equals 1.

Pure JS:

    var objKeys = Object.keys(obj)
    var retval
    for(var i; i < objKeys.length; i++) {
      var value = obj[objKeys[i]]
      if ('age' in value && value.age === 1) {
        retval = value
        break
      }
    }

And that's untested, will only work for an object of objects, has unknown performance, and sure as shit took me more than 1 extra second to write (about 5 minutes once i looked up what the compatibility of the 'in' operator is).

You could use the native .find() function, but that won't work on chrome for android, android browser, IE (any version), safari 7 and older, and opera. Plus you'd still need something like Object.values() in order to convert the "parent" object into an array to search through.

Plus what if i want to find an object in an array and in another object? (which I actually just had to do, which is why i thought of this use case) Well now you've just doubled your code, doubled the amount of tests you need to write, doubled the chance for random bugs to crop up (what happens if one of the object values is undefined? What happens if obj is null?).

With stuff like the lodash cli where you can make builds that literally only contain what you need, the lodash babel plugin that will allow you to require lodash functions and it will build only what you need, or webpack which will tree-shake away everything you don't need (and actually does a better job than the lodash-cli does!), there's no need to avoid lodash like the plague.

I'm not saying include all of it, i'm not saying use it in everything, i'm saying that you should use your brain and include it if it's going to increase the speed that you can develop, reduce the number of bugs you will face, simplify your codebase, and won't negatively impact your users. (after all, a single image will blow the 5kb of js you'll be saving out of the water)