Mac guides for developers
Where your disk space and memory actually go on a Mac you build on, and how to get them back with built-in tools and Terminal commands. Every guide explains what is safe to remove and what is not. WTMemory is an optional shortcut, not a requirement.
Disk space
- Free up disk space on a developer Mac
A step-by-step playbook: measure first, then clear caches, snapshots and downloads safely.
- Why System Data is so large on Mac
What macOS counts as System Data, how to see inside it and what you can safely reduce.
- Where Ollama, Hugging Face and LM Studio store models
Find local AI models, see their sizes and remove the ones you no longer use.
- Delete Xcode DerivedData, DeviceSupport and old simulators
Reclaim the gigabytes Xcode quietly collects, without breaking symbolication.
- Clear npm, pnpm, Yarn, Bun, Cargo and Gradle caches
The right command for each package manager, plus finding old node_modules folders.
- Docker taking up space on Mac
Understand Docker.raw, see usage with docker system df and prune without losing data.
Memory and processes
- What is using my memory on Mac?
Memory pressure, swap and compressed memory explained, and how to find the culprit.
- Port 3000 already in use on Mac
Find the process holding a port with lsof and stop it cleanly, including forgotten dev servers.
Choosing a tool
- CleanMyMac alternative for developers
An honest comparison, plus the free built-in options.