Installing an older version of a package alongside the newer one for debugging purposes

Help
1

I’m trying to find out which version of sway introduced a change in behavior for me (related to Contradiction in man page and regression in multi-output workspace creation · Issue #8522 · swaywm/sway · GitHub). I’d like to build sway 1.8.1 independently of my system and run it with a command like sway181.
I tried copying the sway 1.8.1 package definition, but it required wlroots 0.16. So I copied it too, but I’m just digging myself into a hole because then there are even more dependencies that do not exist anymore that I would have to copy.

I’m sure there is an easy way for me to simply build sway from a specific commit of nixpkgs, but I’m missing it.
I’m using flakes, here’s my repo: GitHub - sweenu/nixfiles: NixOS home and servers configuration

2

Right.

There’s no necessarily “easy” way around this, because if you just create a second nixpkgs instance (add a new channel and then ((import <nixpkgs-whatever> {}).sway)) and get sway that way, you risk other issues. Since that’s low-effort, you can give that a try, but I would expect a lot of issues due to graphical driver impurity on NixOS.

3

This should explain how to install sway 1.8.1

4

Again, that will probably cause some issues as I alluded to earlier.

And do not use nix-env for the love of everything.

5

Thank you guys for your help. Sway 1.8.1 does launch, but has errors making it crash right away. I’m sure this would have worked better for a simpler program.

Here are the errors if you want to know:

00:00:00.062 [ERROR] [wlr] [render/egl.c:204] EGL_EXT_platform_base not supported
00:00:00.062 [ERROR] [wlr] [render/egl.c:506] Failed to create EGL context
00:00:00.062 [ERROR] [wlr] [render/gles2/renderer.c:679] Could not initialize EGL
00:00:00.062 [DEBUG] [wlr] [render/wlr_renderer.c:271] Failed to create a GLES2 renderer. Skipping!
00:00:00.062 [ERROR] [wlr] [render/wlr_renderer.c:333] Could not initialize renderer
00:00:00.062 [ERROR] [sway/server.c:79] Failed to create renderer

I think it’s related to hardware.opengl which is superseded by hardware.graphics which is enabled in my config :man_shrugging: .