Cuber gem

Judgement

What it is

Developer tool

What it does

A Ruby command-line tool that builds an app with buildpacks and deploys it to Kubernetes from a short Cuberfile, generating the manifests for you.

Adopt it when

You want to deploy web apps to Kubernetes without writing YAML and your team is comfortable with Ruby tooling.

Watch out

Small user base, and activity has slowed since early 2026.

Ready for

Usable

Runs as

Command line

Built with

Ruby, Kubernetes and Buildpacks

How established

Established: started 5 years ago, latest release v1.14.0.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Cuber gem → Ruby → GCC → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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