When comparing Hammerspoon vs Magnet, the Slant community recommends Hammerspoon for most people. In the question“What are the best power user tools for macOS?” Hammerspoon is ranked 38th while Magnet is ranked 51st. The most important reason people chose Hammerspoon is:
https://github.com/Hammerspoon/hammerspoon/issues They do fix issues that come from the community.
Ranked in these QuestionsQuestion Ranking
Pros
Pro 1512 issues are closed in the download page in GitHub
https://github.com/Hammerspoon/hammerspoon/issues
They do fix issues that come from the community.
Pro Deeply customizable
Hammerspoon's Lua scripting and broad API allows you to perform any action you can imagine on your mac. It hooks into many OS APIs directly and has some high-level APIs to manipulate things like Spotify or iTunes. See the full list here.

Pro Automate actions based on the operating system
Hammerspoon lets you hook into OS level events and trigger any action you can imagine. From setting up a simple keyboard shortcut to launching a complex workflow using multiple apps and scripts.
Pro Keyboard centric
Easy to learn keyboard shortcuts.
Pro Intuitive handling
Just drag the window to one of the sides of the screen and it snaps there. This is especially useful for those who can't be bothered remembering the shortcuts.
Pro Cheap
At $0.99, it is not that expensive.
Pro Mouse controllable
Supports dragging a window along the edges of the screen to activate.
Pro Do not have to learn or remember keyboard shortcuts
Pro It's often on sale
For example, at the writing of this pro it's currently at $1.
Pro Up to six external displays supported
Cons
Con Has 324 issues on their download page in GitHub
https://github.com/Hammerspoon/hammerspoon/issues
I can not list all the issues.
Con Some knowledge of programming required
Hammerspoon is scripted in the Lua programming language, and some familiarity with programming in general will be needed to use it. Some plugins exist that can be used by adding some files to a specific folder, but this will not give the flexibility that is so key to Hammerspoon
Con Cannot setup custom sizes and window positions
Unfortunately, you can only move windows to preset positions.
Con Can only be purchased from the App Store
Magnet is only available in App Store.
Con Can't hide the menu bar icon
It would've been nice to be able to hide the icon so it doesn't clutter the menu bar.
Con Interference when switching between folders
Default Folder-X app "warns" that Magnet App may interfere with it's ability to switch between folders in Open and Save dialogue boxes.
Con Causes cursor bugs in IntelliJ IDEs
Unfortunately, Magnet causes the caret to bounce around in IntelliJ IDEs, this is very annoying.
