> For the complete documentation index, see [llms.txt](https://concordialang.gitbook.io/concordialang/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://concordialang.gitbook.io/concordialang/upgrade/breaking-changes.md).

# Breaking Changes

Information about breaking changes.

## From `1.x` to `2.x`

Please read [Issue #56](https://github.com/thiagodp/concordialang/issues/56).

## From `0.x` to `1.x`

### **Concordia Compiler**

1. It changed the way that all the plug-in operations are handled. See [Issue #34](https://github.com/thiagodp/concordialang/issues/34) for details.
2. The behavior of the following plug-in commands were affected:

| COMMAND            | NOW                                                                           | BEFORE                                                                                               |
| ------------------ | ----------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------- |
| `plugin-list`      | It lists all the plug-ins **installed for the application**.                  | It listed all the plug-ins **available** in the compiler.                                            |
| `plugin-install`   | It installs a **plug-in and its dependencies**.                               | **Only the plugin's dependencies** were installed, since the plug-in was embedded in the compiler.   |
| `plugin-uninstall` | It uninstalls a **plug-in and its dependencies** using `npm`.                 | **Only the plugin's dependencies** were uninstalled, since the plug-in was embedded in the compiler. |
| `plugin-info`      | It shows information about a plug-in **installed for the application**.       | It shows information about a plug-in **available** in the compiler.                                  |
| `plugin-serve`     | It starts a testing server using a plug-in **installed for the application**. | It started a testing server **available** in the compiler.                                           |

👉 See the [Command Documentation](https://app.gitbook.com/s/-LyZeGFeFI9v0gasbqLP/upgrade/commands.md) to know the commands' syntax.

### **Concordia Language**

No compatibility breaks.

### **Other relevant changes**

External tools used by plug-ins are now installed locally, per project, instead of installed globally. Their direct execution (without using Concordia) is now possible through NPX. For instance, the command `codeceptjs run test.js` must now be executed as `npx codeceptjs run test.js`. This change also allows the installation of different versions of external tools, when needed.

### FAQ

1. *Were there any changes in commands' syntaxes?*

   No, there were not.
2. *Is my configuration file still compatible?*

   It depends. All the properties are still compatible, except for `"plugin"`. Whether your configuration file has that property, you should [update it](/concordialang/upgrade/migration-guide.md).
3. *Is it possible now to install or uninstall a plug-in with NPM ?*

   Yes, it is possible to do both now.


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