# castle v1.2.1 - Table of Contents

> Runtime Hot-Code Upgrade support for Elixir

## Pages

- [Castle](readme.md)
- [Configuring from environment variables](environment-configuration.md)
- [Changelog](changelog.md)

## Modules

- [Castle](Castle.md): Runtime hot-code upgrade support for Elixir releases.

- Exceptions
  - [Castle.Error](Castle.Error.md): Raised when Castle refuses a command or `:release_handler` returns an error.