Setup a caching repository proxy like nexus: https://github.com/sonatype/nexus-public https://github.com/sonatype/nexus-public This is a little server you run

Setup a caching repository proxy like nexus: https://github.com/sonatype/nexus-public https://github.com/sonatype/nexus-public This is a little server you run locally and point your package managers like Gradle, pip, npm, etc. at it and it will grab dependencies from their upstream and cache them locally to be available offline later. Once you get it setup go wild adding every dependency you can think of using so it preloads the cache with good stuff. Unfortunately offline caching for package managers is really hit or miss and rarely a priority to support, so expect some pain getting it all setup. Good luck. Also if you haven't already consider installing and learning languages with a good standard library so you can install them once and do a lot of stuff. Python, go, and deno are really good options with capable standard libraries out of the box. Avoid nodejs or similar minimal/no standard library languages. Rust is surprisingly bad/hard to use offline in my experience too (cargo constantly wants to hit the internet and needs a lot of handholding to play nicely).