So, I wanted to open a Zed encrypt (secure) archive, but Zed encrypt was not packaged in Nixpkgs (and thus available on NixOS). I could have used a virtual machine to install the provided Debian package, but it would have been over in 30 minutes. Instead, I decided to write a derivation: library path overwrite, library preload, C code for overloading syscalls and change hardcoded path, wrapper scripts: in short, it just works! It took about ~9 hours of work. Totally worth it. #shavingtheyak
Here is the derivation to anyone interested: https://github.com/tcheneau/mynixpkgs/tree/master/pkgs/zed-free
Strace, ltrace and LD_DEBUG environment variable were my friends!