Because I’ve worked in at least 3 companies who want to do this. Nobody had a good solution
There are good solutions: Use proper package managers with automated build support like dpkg, pacman, pip or perhaps uv, or even better Guix. Companies not doing that are just cutting corners here.
That can work in some cases, but it’s usually not that great for first party projects where you want to be able to see and edit the code, and most package managers are OS or language specific so they don’t work well with multi-language project or projects using a language that doesn’t have a good package manager (SystemVerilog for example).
There are good solutions: Use proper package managers with automated build support like dpkg, pacman, pip or perhaps uv, or even better Guix. Companies not doing that are just cutting corners here.
That can work in some cases, but it’s usually not that great for first party projects where you want to be able to see and edit the code, and most package managers are OS or language specific so they don’t work well with multi-language project or projects using a language that doesn’t have a good package manager (SystemVerilog for example).