I have some adjacent experience. Not exactly with that, but I have migrated large C++ build systems, migrated systems to Bazel, etc. I've also written a bunch o

I have some adjacent experience. Not exactly with that, but I have migrated large C++ build systems, migrated systems to Bazel, etc. I've also written a bunch of Bazel build scripts for various open-source C++ libraries so I can better integrate them into projects that use Bazel. Bazel is opinionated. The tradeoff here is that if you can make your project match Bazel's opinions, you get a very good experience--but you can have a bad experience if you disagree with Bazel. If you have Bazel experience, you can look at a project and get a quick sense of the distance between how the project is built and how Bazel "wants" to build the project. The payoff is that once you get your Bazel build system, everything seems a lot more trustworthy. No more "make clean". When you run a Bazel command, it just gives you the correct output, very fast, without worrying about what state your build tree is in. You can make any change to your build scripts and just "bazel build" and get the correct result immediately, as long as you aren't trying to bypass how Bazel works. I never have to do anything like run "make" twice. This is something I've never gotten with systems like Make or CMake, which put more of the onus on individual developers to get things correct. So I can kind of shut off my brain when using Bazel. Depending on the particulars of your project, the most straightforward migration path to Bazel will not be obvious. You may need to make certain choices about how much you modify your project to fit Bazel's expectations, versus how much you adapt Bazel to fit your existing project. One example is include paths... do you modify all of your '#include' directives to match how Bazel expects you to write them? Or do you adapt Bazel to do things your way? The difficulty and payoff is highly variable. My experience has generally been positive, but I also have a lot of familiarity with Bazel. It's easy enough to find an example of a project where I'd just never bother migrating to Bazel, or to find examples of projects (even large ones) where migrating is super easy.