Why are you not using Signal / Textsecure or any other of these new apps which have privacy in mind. IIRC they even said Hemlis won't be open source according to their FAQ so I don't think these 3 guys would've pulled this off any better than Telegram even with their dubious encryption.
I can use these apps but in order to be able to recommend it to my friends as an app that can replace Whatsapp or Viber, it should have a comparable UI/UX. I too was concerned about their source availability approach. What will you suggest that meets these criteria?
Seems they changed their mind about open source, according to the comments section "We’ll release the usable parts of the code as free software with the most free license we can. It belongs to the community (and the community paid for it)."
Neat and I like the presentation with asciinema, but couldn't you just use zsh's built in "cmd + r" command to search in history for commands you used in the past? I usually use that + a good old alias for things I use a lot.
Advantage: It's available everywhere and you don't need to remember new commands if you SSH into another server where butler isn't installed.
One of it's features is that it's "A single PHP file of less than 100 lines of code." - Adding all these things you listed would just make it more complicated for no good reason. I'm all for sticking to best practises but in that case it'd make no sense. This is supposed to be deployed easily on shared web hosts, installing dependencies wouldn't work there.
Well it could be 5 lines of code. To edit the output you would have to fork the project for no good reason. Templating exists so you don't have to do stuff like that. Regarding dependencies, you can provide a pre-built zip archive with the dependencies installed already. Then it's just a matter of uploading the folder.