Feature Request: Support native window snapping

[Leroy-X]

I would love to see SwiftShift support the native window snapping feature. Specifically, dragging a window to the side edges to snap it to 1/2 of the screen, and dragging it to the top to maximize it to full screen, just like the built-in system behavior.

Thanks your great app.

[pablopunk]

@Leroy-X seems like it's not possible, we need to use the Accessibility API to move windows and this does not trigger the native behavior. I've explored simulating the mouse event dragging the title bar but that seems to literary move the mouse to the title bar which sucks.

Another thing I could do is make swift shift detect the edges, and then trigger these manually

but that's also not exposed by all apps

needs investigation. This is not a #bug btw, it's a feature request

[Leroy-X]

@pablopunk Thank you for the information, I found that the built-in command supports window snapping, but it must hold down the mouse to drag. btw, The built-in commands seem a bit smoother than SwiftShift, looking forward to SwiftShift being this smooth too.

defaults write -g NSWindowShouldDragOnGesture -bool true

[pablopunk]

@Leroy-X what do you mean "build-in" command? if you are referring to something native, we cannot emulate what apple does. The only way of moving windows programmatically is using the AX API which is not meant for it (I'm just literally recalculating all coordinates a few times per second and "teleporting" the window there). It's as smooth as Apple wants it to be (0). You can see it in all other window managers, they never feel native, because Apple does not provide the APIs needed for it

[Leroy-X]

Thanks for the explanation, yes, I tried multiple window managers and they all felt a bit damped

[chid]

Tackling this from a different angle than native tiling: I've been prototyping magnetic screen-edge snapping inside SwiftShift's own snap system (the same mechanism added in #150 for window-to-window snapping), rather than trying to trigger macOS's native snap — which, as discussed above, the AX API doesn't really expose.

The approach:

• Each display's visibleFrame becomes a set of snap edges, so a window's edge pulls flush to the screen edge while dragging.
• For moves, screen-edge snapping is cursor-driven — you push the cursor toward a screen edge and the window's matching edge snaps flush. This turned out to be important: keying off the window's edge feels broken, because if you grab a window away from the edge you're snapping to, its edge overshoots far past the screen boundary before the cursor gets there.
• Interior seams shared between adjacent monitors are excluded, so windows still cross between displays freely (this needed care with mismatched-size monitors).
• Optional "Hold ⌥ to snap" preference, off by default. (not working at all)

⚠️ Still WIP — multi-monitor behaviour with differently-sized displays isn't fully correct yet, so I'm not putting up a PR until it's solid. Sharing in case it's useful or someone wants to build on it. Branch: feature/screen-edge-snapping.

Can you please take a look to see if this is what you're after? f3b22ba

Not as nice as native, NSWindowShouldDragOnGesture but it is slightly more configurable

[pablopunk]

hey @chid , thanks for the effort. Pls open a PR and we'll continue the discussion in there. I think I'd like

• native-snapping parity: i.e. 2 horizontal halves, 4 quarters, top for full screen...
• just one setting (enable snapping) should be enough. No alt to snap or similar, I'd like to keep it simple (you either want snapping all the time or not). At least for now.
• some sort of indicator that the window is going to snap and where, i.e. just like any other snapping app. not sure how i would implement this visually. The native snapping feels nice, it's vvery minimal: just the window borders (where the window would end up) with an inner shadow

let's start from there!

also I tried your POC and it is snapping but not growing to be half, is that expected?

CleanShot.2026-06-05.at.20.09.44.yafw.balanced.mp4

[chid]

No worries, thanks for making this open source project! I've tried to address your feedback (using AI to code it) though it looked good to me.

With regards to the PoC snapping not rowing, this was actually for my use case (which is why I wanted to code this up), I had an ultrawide and wanted to arrange my terminal windows into sixths which was tedious without a nice hotkey (this app!). Growing the windows would've ruined the experience (and I already have a hotkey for that - as do you).

There are still quite a few janky parts (multi-monitor) and it can probably be improved but would add a bit of complexity (hence my thought to have a separate option key - which I believe replicates "native" behaviour).

Oddly, I have not found anywhere online detailed documentation for the option NSWindowShouldDragOnGesture - with a bit more research, I think it could be possible to trigger it but I expect it won't be stable should Apple change the API.