Containerized build steps

A system comprising:

• data processing hardware;
• and
• memory hardware in communication with the data processing hardware, the memory hardware storing instructions that when executed by the data processing hardware cause the data processing hardware to perform operations comprising:
• receiving a user-defined pipeline from a user device associated with a user, the user-defined pipeline comprising a set of build steps with build step criteria for a build step process, the set of build steps comprising a compiling build step, a unit test build step, and a deployment build step, the build step process configured to generate, as output, a deployment container using the set of build steps, the deployment container comprising a software application configured to execute on a distributed system;
• receiving a notification indicating that the user is authenticated and authorized to access one or more private registries identified by a respective build step of the set of build steps;
• and
• based on the received notification:
• executing the compiling build step to build executable code of the software application from source code originating from the one or more private registries;
• executing the unit test build step to determine that the executable code of the software application satisfies the build step criteria;
• and
• executing the deployment build step to package the executable code of the software application for the deployment container, the deployment container comprising a runtime environment for the executable code of the software application.