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Question about `sequence`. Is there a way to avoid 2 boilerplate `fix()`s in the below example to get that data type? Is there any on-going development on this, now that `Kind` is being deprecated?
```val listOfOptionalNumbers: List&lt;Either&lt;Int, Int&gt;&gt; =
     listOf(1.right(), 2.right(),3.right())
val result: Either&lt;Int, List&lt;Int&gt;&gt; = 
     listOfOptionalNumbers.sequence(Either.applicative()).map { it.fix() }.fix()```

One option is to utilise `either.eager`:
```fun &lt;E, A&gt; Iterable&lt;Either&lt;E, A&gt;&gt;.sequence(): Either&lt;E, Iterable&lt;A&gt;&gt; =
    either.eager { this@sequence.map { it.bind() } }

listOf(1.right(), 2.right(), 3.right()).sequence()```

Or more generally:
```fun &lt;E, A, B&gt; Iterable&lt;A&gt;.traverse(f: (A) -&gt; Either&lt;E, B&gt;): Either&lt;E, Iterable&lt;B&gt;&gt; =
    either.eager { this@traverse.map { f(it).bind() } }

fun &lt;E, A&gt; Iterable&lt;Either&lt;E, A&gt;&gt;.sequence(): Either&lt;E, Iterable&lt;A&gt;&gt; =
    this.traverse(::identity)```

These methods will be added in the next version of Arrow, since we want to get rid of `fix` and by extension `Kind`.

This is the PR for `Either`. <https://github.com/arrow-kt/arrow-core/pull/272>

Using `either` or `either.eager` works too as <@UQT3B0JSD> mentioned!