cup
by sergi0g
Cup is a small, fast tool that checks whether the Docker container images you run have newer versions available. It has a command-line interface and a web page, and it can output results as JSON for other tools to use.
- Stars
- 1.4k
- Licence
- AGPL-3.0
- Runs on
- A small server
- Setup
- Moderate
- Language
- Rust
- Age
- 867 days
What you can do with it
- Check which of your running Docker containers have newer image versions available
- View update status in a web dashboard or from the command line
- Export JSON results to feed dashboards, webhooks or scheduled jobs
Make money with it
A freelancer could offer a low-cost server maintenance service that uses Cup to report on outdated containers for clients.
An idea, not financial advice. Check the licence before charging for anything built on it.
Ways a business could use it
- Keep the containers behind a company's internal tools up to date without manual checking
- Set up a regular update report for client servers you manage as a freelancer
Can you use it commercially?
Free to use. Anything you distribute that includes it must be open-sourced under the same licence. Running it as an online service also counts, so a hosted version must offer its source.
Not legal advice. Read the project's licence file before building a product on it.
Getting it running
It is a small Rust binary that can also run as a Docker container, with installation steps in the online documentation.
Follow the official instructions in the project README.
Things to check
- Only checks for updates; it does not apply them or trigger notifications by itself
- Described by its author as a work in progress with fewer features than alternatives
- AGPL-3.0 licence may matter if you modify and offer it as a service
Who's talking about it
- raiscui (gh-trends): GitHub trends — 2026-10-28 (daily release) Featured in a roundup
Checked 30 Oct 2026. Summary drafted by AI from the project's README.
