TL;DR

Make and CMake are gradually being replaced by more powerful, flexible, and scalable build systems like Bazel and Nix. These new tools offer better dependency management, faster builds, and cross-platform support. If you're still using Make for anything larger than a pet project, it might be time for an upgrade.

The Old Guard: Make and CMake

Before we explore the new kids on the block, let's pour one out for our old friends:

  • Make: The granddaddy of build systems. Simple, ubiquitous, but shows its age when dealing with complex projects.
  • CMake: The evolution of Make. More powerful and flexible, but can become a tangled mess in large projects.

These tools have served us well, but as projects grow in complexity and scale, their limitations become more apparent. Enter the new generation of build systems.

The Rising Stars: Bazel and Nix

Bazel: Google's Secret Weapon

Bazel, originally developed by Google, is like the Swiss Army knife of build tools (but cooler and without the corkscrew). It's designed for large-scale, multi-language projects and offers some serious advantages:

  • Hermetic builds: Bazel isolates each build step, ensuring reproducibility.
  • Incremental and parallel builds: Only rebuild what's necessary, and do it fast.
  • Language-agnostic: Works with Java, C++, Python, and more.
  • Remote caching and execution: Speed up builds by leveraging distributed resources.

Let's see Bazel in action with a simple example:


# BUILD file
load("@rules_cc//cc:defs.bzl", "cc_binary")

cc_binary(
    name = "hello-world",
    srcs = ["hello-world.cc"],
)

This BUILD file defines a C++ binary target. To build it, you'd run:


bazel build //:hello-world

Simple, right? But Bazel's real power shines in large, complex projects with multiple languages and dependencies.

Nix: The Functional Approach

If Bazel is the Swiss Army knife, Nix is the laser-guided missile of build systems. It takes a unique, functional approach to package management and building:

  • Reproducible builds: Nix ensures that builds are bit-for-bit reproducible.
  • Declarative configuration: Describe what you want, not how to get it.
  • Atomic upgrades and rollbacks: No more "it worked on my machine" issues.
  • Multi-user support: Different users can have different environments on the same system.

Here's a taste of Nix:


{ stdenv, fetchFromGitHub }:

stdenv.mkDerivation rec {
  pname = "hello-world";
  version = "1.0.0";

  src = fetchFromGitHub {
    owner = "example";
    repo = "hello-world";
    rev = "v${version}";
    sha256 = "0000000000000000000000000000000000000000000000000000";
  };

  buildPhase = "gcc -o hello-world hello-world.c";
  installPhase = "mkdir -p $out/bin; install -t $out/bin hello-world";
}

This Nix expression defines how to build a "hello-world" program from a GitHub repository. It's declarative, version-controlled, and reproducible.

Practical Use Cases: When to Choose What

So, when should you reach for these new tools? Let's break it down:

Choose Bazel when:

  • You're working on a large, multi-language project
  • Build speed is crucial (who are we kidding, it always is)
  • You need fine-grained control over dependencies
  • You want to leverage remote caching and execution

Go for Nix when:

  • Reproducibility is your top priority
  • You're managing complex system configurations
  • You need to support multiple user environments
  • You're into functional programming (and want your builds to be too)

The Catch: It's Not All Sunshine and Rainbows

Before you rush to rewrite all your Makefiles, consider these potential pitfalls:

  • Learning curve: Both Bazel and Nix have steep learning curves. Be prepared to invest time in understanding their concepts.
  • Ecosystem support: While growing, the ecosystem for these tools isn't as mature as Make or CMake. You might need to write custom rules or packages.
  • Team buy-in: Switching build systems is a significant change. Make sure your team is on board and ready for the transition.

Making the Transition: Tips and Tricks

Ready to take the plunge? Here are some tips to ease the transition:

  1. Start small: Begin with a single module or subproject. Don't try to boil the ocean on day one.
  2. Invest in training: These tools are powerful but complex. Invest in proper training for your team.
  3. Leverage the community: Both Bazel and Nix have active communities. Don't hesitate to ask for help.
  4. Be patient: The benefits of these systems often become apparent over time. Don't expect instant miracles.

The Future of Build Systems

As we look to the future, what can we expect from build systems?

  • Increased focus on reproducibility: As software supply chain attacks become more common, reproducible builds will be crucial.
  • Better integration with cloud services: Expect tighter integration with cloud-based build and CI/CD services.
  • More language-agnostic tools: The trend towards polyglot projects will drive the development of more flexible build systems.
  • AI-assisted build optimization: Don't be surprised if AI starts helping us optimize our build configurations.

Wrapping Up: To Build or Not to Build?

The world of build systems is evolving rapidly. While Make and CMake aren't going away anytime soon, tools like Bazel and Nix offer compelling advantages for modern, complex projects. The key is to evaluate your project's needs and choose the tool that best fits your requirements.

Remember, the best build system is the one that lets you focus on writing code, not fighting with build scripts. So, whether you stick with Make or dive into the world of Bazel and Nix, choose the tool that makes your life easier and your builds faster.

"The best build is the one you don't notice." - Anonymous Developer (probably)

Now, if you'll excuse me, I have a Makefile to rewrite... in Nix. Wish me luck!