---
area: "Changes"
parent: "Changes"
url: "https://unpoly.com/changes/0.21.0"
released: "2016-03-13"
---
<nav aria-label="Unpoly docs">[All docs](https://unpoly.com/index.md) · [Changes](https://unpoly.com/changes.md)</nav>

# Version 0.21.0

Released on March 13, 2016 with [8 commits](https://github.com/unpoly/unpoly/commits/v0.21.0)

## Compatible changes {#compatible-changes}

- New function [`up.macro()`](https://unpoly.com/api/up.macro.md). This registers a [compiler](https://unpoly.com/api/up.compiler.md) that is run before all other compilers.
- [`up.compiler()`](https://unpoly.com/api/up.compiler.md) has a new options `{ priority }`. Compilers with higher priorities are run first.
- Fix a bug where trying to apply another transition on an element could throw a _Maximum call stack exceeded_ error if the element was already transitioning.

## Breaking changes {#breaking-changes}

- 🧩 `up-toggle` has been renamed to `up-switch`