In the specifications in the above table of contents, the keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" are to be interpreted as described in [RFC 2119](http://tools.ietf.org/html/rfc2119) (Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997).
Application bundle builders can create a [bundle](bundle.md) directory that includes all of the files required for launching an application as a container.
The bundle contains OCI [configuration files](config.md) where the builder can specify host-independent details such as [which executable to launch](config.md#process-configuration) and host-specific settings such as [mount](runtime-config.md#mount-configuration) locations, [hook](runtime-config.md#hooks) paths, Linux [namespaces](runtime-config-linux.md#namespaces) and [cgroups](runtime-config-linux.md#control-groups).
Because the configuration includes host-specific settings, application bundle directories copied between two hosts may require configuration adjustments.
[Hook](runtime-config.md#hooks) developers can extend the functionality of an OCI-compliant runtime by hooking into a container's lifecycle with an external application.
Example use cases include sophisticated network configuration, volume garbage collection, etc.
#### Runtime Developers
Runtime developers can build runtime implementations that run OCI-compliant bundles and container configuration, containing low-level OS and host specific details, on a particular platform.
Everyone is welcome to participate in the [BlueJeans call][BlueJeans].
An initial agenda will be posted to the [mailing list](#mailing-list) earlier in the week, and everyone is welcome to propose additional topics or suggest other agenda alterations there.
Minutes are posted to the [mailing list](#mailing-list) and minutes from past calls are archived to the [wiki](https://github.com/opencontainers/specs/wiki) for those who are unable to join the call.
The sign-off is a simple line at the end of the explanation for the patch, which certifies that you wrote it or otherwise have the right to pass it on as an open-source patch.
The rules are pretty simple: if you can certify the below (from [developercertificate.org](http://developercertificate.org/)):
Read more on [How to Write a Git Commit Message](http://chris.beams.io/posts/git-commit/) or the Discussion section of [`git-commit(1)`](http://git-scm.com/docs/git-commit).
1. Separate the subject from body with a blank line
2. Limit the subject line to 50 characters
3. Capitalize the subject line
4. Do not end the subject line with a period
5. Use the imperative mood in the subject line
6. Wrap the body at 72 characters
7. Use the body to explain what and why vs. how
* If there was important/useful/essential conversation or information, copy or include a reference
8. When possible, one keyword to scope the change in the subject (i.e. "README: ...", "runtime: ...")