# How to Upgrade

## Versioning

Concordia Compiler's versions are based on [Semantic Versioning](https://semver.org).

Although Semantic Versioning is conceived for [API](https://en.wikipedia.org/wiki/Application_programming_interface)s instead of for applications, we adopt a very similar convention. Thus, changes become predictable and you can know, from the version numbers, when a version is no more compatible with a previous version.

Given a version `MAJOR`.`MINOR`.`UPDATE`:

* `MAIOR` is increased when the **Compiler** or the **Language** is no more compatible with the previous version.
* `MINOR` is increased when adding functionality in a backwards-compatible manner.
* `UPDATE` is increased when there are fixes, little changes or little novelties - all of them backwards-compatible.

Examples:

* `0.2.0` is compatible with `0.1.0`
* `0.1.1` is compatible with `0.1.0`
* `1.0.0` is *not* compatible with `0.2.0`

## Upgrade

{% hint style="success" %}
NPM upgrades without breaking compatibility (when `MINOR`or`UPDATE changes`).
{% endhint %}

{% hint style="warning" %}
For migrating a `MAJOR` version (*e.g.*, `1.x` to `2.x`) please read our [Migration Guide](https://concordialang.gitbook.io/concordialang/upgrade/migration-guide).
{% endhint %}

To upgrade a **local installation**:

```bash
npm upgrade concordialang
```

To upgrade a **global installation**:

```bash
npm upgrade -g concordialang
```