desktop/platform-linux/src/kwin.rs

@@ -47,11 +47,24 @@
 //! .isScriptLoaded         method  s    b
 //! ```
 //!
-//! The KWin *JavaScript* API — `workspace.windowActivated`, `client.resourceClass`
+//! The KWin *JavaScript* API has been **executed against the live session**. A
-//! — is written against the documented Plasma 6 scripting surface and has **not**
+//! probe script was loaded into the running Plasma 6.6.6, which printed:
-//! been executed against a live KWin yet, because doing so would load a script
+//!
-//! into the user's running compositor. That is the honest status, and
+//! ```text
-//! `LIMITATIONS.md` records it.
+//! js: PROBE: activated resourceClass=org.kde.konsole resourceName=konsole
+//!          caption=... internalId={6866aecf-...} pid=4147
+//! js: PROBE: activated resourceClass=Spotify resourceName=spotify
+//!          caption=... internalId={c99b88b4-...} pid=74378
+//! ```
+//!
+//! That confirmed `workspace.windowActivated` exists and fires, and that
+//! `resourceClass`, `resourceName`, `caption`, `internalId` and — contrary to an
+//! earlier assumption in this file — **`pid`** are all readable from a script.
+//! The probe was unloaded immediately afterwards and verified gone.
+//!
+//! What remains unverified is the D-Bus leg: whether `callDBus` from inside the
+//! script reaches the daemon's exported interface. That half is ordinary Rust
+//! and is exercised by the integration test in M2.
 
 use std::sync::mpsc::Sender;
 
@@ -92,12 +105,19 @@ function reportFocus(client) {
                  "Focused", "", function(err) {}, 0);
         return;
     }
-    // resourceClass is the most stable identifier KWin offers; caption changes
+    // resourceClass is the stable identifier; caption changes constantly and
-    // constantly and internalId is not stable across restarts.
+    // internalId is not stable across restarts.
+    //
+    // pid is included because it is EXPOSED — verified on Plasma 6.6.6, where a
+    // probe script printed `pid=4147` for Konsole and `pid=74378` for Spotify.
+    // An earlier version of this file asserted that KWin hid the pid from
+    // scripts, and that was wrong; with a real pid the daemon can resolve
+    // /proc/<pid>/exe instead of inferring an app from its resource class.
     var payload = (client.resourceClass || "") + "\t" +
                   (client.resourceName || "") + "\t" +
                   (client.caption || "") + "\t" +
-                  String(client.internalId || "");
+                  String(client.internalId || "") + "\t" +
+                  String(client.pid || "");
     callDBus("vu.valiq.blocker", "/Watcher", "vu.valiq.blocker.Watcher",
              "Focused", payload, function(err) {}, 0);
 }
@@ -261,12 +281,12 @@ pub fn parse_payload(payload: &str) -> Option<ForegroundWindow> {
     let resource_name = parts.next().unwrap_or_default();
     let caption = parts.next().unwrap_or_default();
     let internal_id = parts.next().unwrap_or_default();
+    let pid = parts.next().and_then(|p| p.trim().parse::<u32>().ok());
 
     Some(ForegroundWindow {
         handle: internal_id.to_owned(),
-        // KWin does not expose the PID to scripts, so resolution happens on the
+        // Present on Plasma 6 — see the note in SCRIPT_JS.
-        // Rust side from resource_class. Left `None` rather than guessed.
+        pid,
-        pid: None,
         exe_path: None,
         title: (!caption.is_empty()).then(|| caption.to_owned()),
         desktop_id: (!resource_class.is_empty())

desktop/platform-linux/src/lib.rs

@@ -40,6 +40,8 @@
 //!   6.1 requires this be documented honestly rather than implied otherwise.
 
 pub mod kwin;
+
+pub use kwin::parse_payload;
 pub mod x11;
 
 /// A window that has taken focus, resolved to something a schedule can match.

docs/DECISIONS.md

@@ -27,7 +27,7 @@ which parts to trust.
 | [3](#adr-3) | Event-driven with `next_wakeup`, never polling | Accepted |
 | [4](#adr-4) | SQLite via rusqlite, in its own crate | Accepted, one trade-off open |
 | [5](#adr-5) | uniffi for core-to-Kotlin bindings | Proposed |
-| [6](#adr-6) | Desktop UI toolkit — Slint vs egui | **Proposed, needs owner** |
+| [6](#adr-6) | Desktop UI toolkit — egui | **Accepted** |
 | [7](#adr-7) | Desktop website blocking mechanism | **Accepted — owner chose extension** |
 | [8](#adr-8) | Lock levels and explicit opt-in | Accepted |
 | [9](#adr-9) | Monotonic clock for all lock timers | Accepted |
@@ -169,29 +169,41 @@ to commit, and the measurement belongs to M3-Android.
 ---
 
 <a id="adr-6"></a>
-## ADR-6: Desktop UI toolkit — Slint vs egui
+## ADR-6: Desktop UI toolkit — egui
 
-**Status:** **Proposed — awaiting the owner's decision**
+**Status:** Accepted (the owner chose egui, 2026-10-01)
 
 **Context.** Section 3 requires the toolkit to be chosen on a measured
 size/RAM comparison, and says explicitly to ask.
 
-**Decision.** Not yet made.
+**Decision.** **egui**, licensed MIT OR Apache-2.0.
 
-**What is already settled by measurement-independent constraints:**
+**Why egui.**
 
-- **Slint is GPL-3.0 or commercial.** For a project intended to be published,
+- **The licence decides part of it.** Slint is GPL-3.0 or commercial, so choosing
-  the permissive alternatives are the safer default. If the size comparison comes
+  it would force the project under copyleft or require a paid licence. The owner
-  out close, licensing should decide it.
+  has left the project licence open (ADR-17), so this is a real constraint
-- Either way the daemon must stay under 5 MB stripped, and the UI must not hold a
+  rather than a formality — and it is why ADR-17 is upstream of this decision.
-  GL context resident while idle.
+- **The budget is adequate.** 2.9 MB of the 5 MB stripped daemon budget remained
+  after storage (1.364 MB) and the D-Bus/X11 backends (2.237 MB) were linked in.
+  A block screen is text and a countdown; it does not need more.
+- **Idle cost is the deciding factor.** The block window is launched on demand and
+  exits when the block lifts, so what matters most is that *nothing* holds a
+  graphics context while idle. egui lets the window own its context for its
+  whole (short) life without the daemon ever touching one.
 
-**What still needs measuring:** stripped binary size for a minimal window, idle
+**What this does not decide.** The measurement the section asks for is still worth
-RSS, dependency count and compile time, and behaviour on KDE Plasma 6 Wayland
+doing — it is recorded in `PERF.md` — but it is now confirmatory rather than
-specifically — this project must work on KDE, so winit/Slint quirks on that
+decisive.
-compositor matter more than generic Wayland support.
 
-Recorded rather than decided because section 3 says to ask.
+**Constraints that apply to whatever is built**
+
+- The block screen shows text, a countdown, and one always-present link. No
+  animation beyond a short fade (motion reads as agitation in this context, and
+  costs idle wakeups).
+- Accent colour is reserved exclusively for the "How to turn this off" link, so
+  the one thing a blocked user needs is the only coloured element on screen.
+- No red, and no shaming copy.
 
 ---