From 44d310903ed84d01f2204b6b0f57bb38f297d9b9 Mon Sep 17 00:00:00 2001
From: atagen <boss@atagen.co>
Date: Sun, 15 Feb 2026 11:55:28 +1100
Subject: [PATCH] init

---
 flake.lock         |  7 +++++
 flake.nix          | 35 +++++++++++++++++++++++++
 niri-s76-bridge.nu | 64 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 106 insertions(+)
 create mode 100644 flake.lock
 create mode 100644 flake.nix
 create mode 100755 niri-s76-bridge.nu

diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..5999137
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,7 @@
+{
+  "nodes": {
+    "root": {}
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..8b57775
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,35 @@
+{
+  description = "Passes focused Niri window's PID to System76 Scheduler.";
+
+  outputs = _: {
+
+    nixosModules.default =
+      {
+        config,
+        lib,
+        pkgs,
+        ...
+      }:
+      {
+        options.services.niri-s76-bridge = {
+          enable = lib.mkEnableOption "niri-s76-bridge service";
+        };
+
+        config = lib.mkIf config.services.niri-s76-bridge.enable {
+          systemd.user.services.niri-s76-bridge = {
+            description = "Bridge between niri and System76 Scheduler";
+            after = [ "graphical-session.target" ];
+            partOf = [ "graphical-session.target" ];
+            wantedBy = [ "graphical-session.target" ];
+
+            serviceConfig = {
+              Type = "simple";
+              ExecStart = "${pkgs.nushell} ${./niri-s76-bridge.nu}";
+              Restart = "on-failure";
+              RestartSec = "5";
+            };
+          };
+        };
+      };
+  };
+}
diff --git a/niri-s76-bridge.nu b/niri-s76-bridge.nu
new file mode 100755
index 0000000..2b5a2b1
--- /dev/null
+++ b/niri-s76-bridge.nu
@@ -0,0 +1,64 @@
+
+def main [] {
+    def notify-scheduler [proc_id: int] {
+        print $"Forwarding PID ($proc_id) to scheduler"
+        busctl call com.system76.Scheduler /com/system76/Scheduler com.system76.Scheduler SetForegroundProcess u $"($proc_id)"
+    }
+    
+    print "niri-s76-bridge started"
+    niri msg -j event-stream | lines | reduce --fold [] { |line, windows|
+        let event = $line | from json
+        let event_type = $event | columns | first
+        
+        match $event_type {
+            "WindowsChanged" => {
+                mut acc = $windows
+                for w in $event.WindowsChanged.windows {
+                    if $w.pid != null and $w.is_focused {
+                        notify-scheduler $w.pid
+                    }
+                    if $w.pid != null {
+                        let existing = $acc | where id == $w.id
+                        if ($existing | is-empty) {
+                            $acc = ($acc | append {id: $w.id, pid: $w.pid})
+                        }
+                    }
+                }
+                $acc
+            }
+            "WindowOpenedOrChanged" => {
+                let w = $event.WindowOpenedOrChanged.window
+                if $w.is_focused and $w.pid != null {
+                    notify-scheduler $w.pid
+                }
+                if $w.pid != null {
+                    let existing = $windows | where id == $w.id
+                    if ($existing | is-empty) {
+                        $windows | append {id: $w.id, pid: $w.pid}
+                    } else {
+                        $windows
+                    }
+                } else {
+                    $windows
+                }
+            }
+            "WindowFocusChanged" => {
+                let focused_id = $event.WindowFocusChanged.id
+                if $focused_id != null {
+                    let match = $windows | where id == $focused_id
+                    if not ($match | is-empty) {
+                        let focused_pid = $match.0.pid
+                        if $focused_pid != null {
+                            notify-scheduler $focused_pid
+                        }
+                    }
+                }
+                $windows
+            }
+            "WindowClosed" => {
+                $windows | where id != $event.WindowClosed.id
+            }
+            _ => $windows
+        }
+    }
+}