Content deployment systems and methods are provided for continuously integrating and deploying selected content items from a plurality of content sources into a specific release as part of the specific release. For example, a first content source stores a plurality of first content items for potential inclusion in the specific release. A manifest record for the specific release specifies release items that are allowed to be part of the specific release. A proxy can periodically retrieve selected ones of the first content items that are specified in the manifest record, and push them to a content publishing engine. Any content items that are not specified in the manifest record are rejected by the proxy. A processor of the content publishing engine can allow for continuous integration of the selected ones of the first content items into the specific release.