Things I would build if I worked at GitHub
These are great, but they're bugfixes.  You'd finish them in the first few months.  Then what are you going to do?  Stare at an aquarium all day?  Here's what I would build if I worked at github:* Github CI - simple CI for every language, integrating with:* Github Artifacts - repository for versioned deployable build packages (binaries, tar.gz files, ios builds, android builds...), integrating with:* Github Deploy - deploy tooling for deploying runnable artifacts or artifact combinations to either your own infrastructure, or to aws/azure/google, or:* Github Cloud - instances/containers as a serviceand the 'fork' button would be a pulldown that would include the options 'fork', 'fork and test', 'fork, test and deploy'.  Now that's a nice little 3-4 year career.