bazel_rules_qt VS rules_python

I migrated a mid-size polyglot project from Makefiles to Bazel and C++ was a large component of the project.

Some obstacles:

1. Building with QT5 MOC & UI files. There is a great library[0] for it but it has hardcoded paths to the QT binaries and header files assuming a system-wide installation. I had to patch the rule to point to our QT location. Then it worked fine.

2. There is no rule to build a fully static library[1]. Since we were shipping a static library in our Makefile system, that was somewhat annoying.

3. We were using system links like `$PROJECT_ROOT/links/GCC/vX.Y.Z/ -> /opt/gcc/...` to point to all the build tools, but these didn't work in Bazel I think because it required absolute paths for any binaries it calls. We ended up putting them in a .bazelrc but we would need a different one for Windows and Linux.

4. Not good integration with IDEs

Ultimately we did not keep using Bazel because we were building Python binaries and py_binary was too slow on Windows. And we didn't have enough time to write a PyInstaller rule.

[0]: https://github.com/justbuchanan/bazel_rules_qt

[1]: https://github.com/bazelbuild/bazel/issues/1920

Python support in Bazel now looks more promising with `rules_python`: https://github.com/bazelbuild/rules_python

`rules_go` to my understanding is great too.

Over years, Bazel is not as opinionated as before, mostly because adoptions in different orgs force it to be so.

I have personally run converted build systems to Bazel, and use it for personal projects as well.

Bazel 1.0 was released in October 2019. If you were using it "a few years ago", I'm guessing you were using a pre-1.0 version. There's not some cutoff where Bazel magically got easy to use, and I still wouldn't describe it as "easy", but the problem it solves is hard to solve well, and the community support for Bazel has gotten a lot better over the past years.

https://github.com/bazelbuild/rules_python

The difficulty and complexity of using Bazel is highly variable. I've seen some projects where using Bazel is just super simple and easy, and some projects where using Bazel required a massive effort (custom toolchains and the like).

load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive") #------------------------------------------------------------------------------ # Python #------------------------------------------------------------------------------ # enable python rules http_archive( name = "rules_python", url = "https://github.com/bazelbuild/rules_python/releases/download/0.2.0/rules_python-0.2.0.tar.gz", sha256 = "778197e26c5fbeb07ac2a2c5ae405b30f6cb7ad1f5510ea6fdac03bded96cc6f", )