The latest articles on DEV Community by Dominik Bullo (@dominikbullo). https://dev.to/dominikbullo https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3949581%2F015fbdbc-b772-497f-b097-f343f2fc19fa.jpeg https://dev.to/dominikbullo en Dominik Bullo Sun, 24 May 2026 21:15:46 +0000 https://dev.to/dominikbullo/half-a-day-not-a-week-one-nix-flake-for-three-machines-515k https://dev.to/dominikbullo/half-a-day-not-a-week-one-nix-flake-for-three-machines-515k <p>My personal MacBook had a disagreement with a little bit of water. Got drowned. Basically all data lost.</p> <p>When it came back from repair, I cloned the repo and ran one command: <code>nix run .#build-switch</code>. About ninety minutes later, the Dock looked right, zsh was configured, Homebrew was installed with all the casks, and my terminal opened with the correct font.</p> <p>I have never not appreciated that.</p> <p>The setup is one <a href="https://nixos.wiki/wiki/Flakes" rel="noopener noreferrer">Nix flake</a> managing three machines: personal MacBook, work MacBook, NixOS desktop. They share a 70+ package core — same shell, same tools, same muscle memory everywhere. The 10% that differs (work casks, personal side projects, different Dock layouts) lives in per-host config.</p> <p>A few things that were more interesting to build than I expected:</p> <ul> <li> <strong>Declarative Dock management</strong> — an activation script that diffs the current layout against a declared list, removes extras, adds missing entries. Fresh machine: correct Dock, automatically.</li> <li> <strong>launchd automation with guard files</strong> — one-time agents that run once, write a sentinel file, then skip on every subsequent rebuild. Colima starts at login. Spotlight loses Cmd+Space to Raycast. All in config.</li> <li> <strong>Brave profile launchers</strong> — generated shell scripts (<code>brave-personal</code>, <code>brave-work</code>) that appear in PATH automatically.</li> </ul> <p>The part I found hardest to explain to people: this isn't a shell script that installs things. It's a description of desired state. Remove a package from the config and rebuild — it's gone. The system converges to what the config says, not what happened to accumulate over years.</p> <p>The full post covers the four-layer architecture, the shared/per-host split in detail, how agenix + YubiKey handle secrets, and the real trade-offs (first setup is ~90 minutes; the Nix language will confuse you; "reproducible" has limits macOS permissions won't let you cross).</p> <p><strong><a href="https://bullo.sk/blog/nix-darwin-multi-host-setup" rel="noopener noreferrer">Read the full post on bullo.sk →</a></strong></p> <p>Config repo: <a href="https://github.com/dominikbullo/nix-config" rel="noopener noreferrer">github.com/dominikbullo/nix-config</a></p> automation cli productivity tooling