I've been a long time Blink user and recently switched to ShellFish:
https://apps.apple.com/us/app/secure-shellfish-ssh-client/id...
Like Blink it is fast, but it also has great support for the files app & shortcuts, and widgets. The widgets are actually useful because they have the option to turn on "Location Persistence" which must use an API similar to navigation apps.
[1] I wonder how long this will last before Apple wises up.
Also consider PyTO for Python on iOS. It’s fully open source and in active development, but much less polished than Pythonista which unfortunately has been moribund for several years now.
Further development options include Codea that’s an excellent Lua dev environment, and Apple’s Swift Playgrounds that provides access to SwiftUI, and later this year will enable uploading apps developed in it to the store.