- Colour replacer (multiple languages) - flood fill a colour manually with file manipulation
- Docker Compose for deployment of a full stack application: database, cache layer (Redis), NGX or Apache web server, JavaScript front-end all deployed with Docker
- Build an OAuth2 authorisation server (using a library) with PKCE (Proof Key Code Exchange) - read the OAuth docs
- Implement a Sudoku solver - bonus points for using concurrency, detect when multiple solutions or no solutions exist
- Extract, transform, load task - like pulling Tweets - with Apache Airflow - pull some data from the internet once an hour, or once a day
From 5 advanced coding projects to expose you to complex concepts by Bennet Garner