feat: support Apple Vision Pro simulator slimming and speed up no-reboot slims

CLAUDE.md

@@ -4,7 +4,7 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 
 ## What this is
 
-simslim runs many more iOS, tvOS, and watchOS simulators on one Mac by disabling the background
+simslim runs many more iOS, tvOS, watchOS, and visionOS simulators on one Mac by disabling the background
 daemons a simulator doesn't need, cutting each simulator's memory ~4x. It is a Go
 CLI plus a SwiftUI macOS app that wraps it. Everything is driven through
 `xcrun simctl`; the tool only ever touches the simulators you point it at, never
@@ -67,20 +67,28 @@ testable capability needs. `doctor` reads a booted simulator's disabled labels
 and reports any required feature whose daemons are down, exiting non-zero — a CI
 preflight. `features_test.go` asserts every feature label is slimmable.
 `slim.go`'s `ensure()` rejects a non-empty slim profile on runtimes older than
-iOS/tvOS 18.5 or watchOS 11.5 before booting or mutating the device, then reads the currently disabled
+iOS/tvOS 18.5, watchOS 11.5, or visionOS 2.5 before booting or mutating the device, then reads the currently disabled
 labels, computes a `delta` against the desired set, and applies the changes with
 `launchctl disable/enable` run inside the simulator via `simctl spawn`, a pool of
 `spawnWorkers` (8) at a time. It reboots
 and reads the state back before reporting persistence. `on` disables the profile;
 `off` remains available on every runtime and re-enables the whole managed set.
 `Profile.DesiredForDevice` keeps `com.apple.homed` enabled on watchOS, which
-re-enables that service after startup. Slimming, verification, and per-device
+re-enables that service after startup, and `com.apple.mobileassetd` on visionOS,
+whose simulated surroundings are mobile assets. Slimming, verification, and per-device
 status totals use this platform-specific profile; `Profile.Desired` remains the
 platform-independent catalog for profile editors. `Device.Platform` identifies
-iOS, tvOS, or watchOS; an empty platform defaults to iOS for library callers.
+iOS, tvOS, watchOS, or visionOS (CoreSimulator's `xrOS` runtimes); an empty platform defaults to iOS for library callers.
 `EnableSlimNoReboot` (`on --no-reboot`) skips the reboot: it runs `launchctl
 disable` + `launchctl bootout` per label so the daemon stops in the current boot
 session, which is the only slimming possible on runtimes older than iOS 18.5.
+Before that per-label pass, `unloadInBatch` stops most labels at once: it finds
+each label's job plist under the runtime's RuntimeRoot (`Device.RuntimeID` →
+`runtimeRoot`, used only when the plist's own `Label` matches) and passes them to
+one `launchctl unload -w` per 64 plists, which writes the same override as
+`disable` and removes the job like `bootout`. It then reads `print-disabled` and
+`launchctl list` back, and only labels still enabled or loaded take the
+per-label path; any failure in the batch just means more labels do.
 
 **The offline fast path.** On a runtime with persistent overrides `ensureOffline`
 takes over: `disabled_store.go` writes the overrides directly and boots the
@@ -90,7 +98,8 @@ there too — an override only takes effect at the next boot, so `ensure` reads
 live state, returns early when the profile already matches, and otherwise spends
 the shutdown the device already owed before handing off. There is no shell inside
 any iOS runtime (`RuntimeRoot/bin` holds only `df` and `launchctl`), so batching
-transitions through a spawned `/bin/sh` is not an option; the pool is. `launchd_sim` is a *host* process, so that store is not in the
+transitions through a spawned `/bin/sh` is not an option; the offline path uses
+the pool. `launchd_sim` is a *host* process, so that store is not in the
 device's data directory — it sits beside the device's `launchd.log` in
 `/private/var/tmp/com.apple.CoreSimulator.SimDevice.<UDID>/disabled.plist`, keyed
 only by UDID. It is an undocumented CoreSimulator detail, so treat it as

README.md

@@ -1,6 +1,6 @@
 # simslim
 
-Run a lot more iOS, Apple TV (tvOS), and Apple Watch (watchOS) simulators on one Mac by turning off the background daemons a simulator doesn't need.
+Run a lot more iOS, Apple TV (tvOS), Apple Watch (watchOS), and Apple Vision Pro (visionOS) simulators on one Mac by turning off the background daemons a simulator doesn't need.
 
 A freshly booted iOS simulator starts around 180 background services: Siri, Spotlight indexing, photo analysis, News, wallpaper posters, iCloud sync, and so on. None of it matters when you're using the simulator for development, testing, or CI. simslim switches those services off, which cuts each simulator's memory roughly 4x. On the same laptop you go from a handful of simulators to a screenful.
 
@@ -38,18 +38,24 @@ or
 go install github.com/mobai-app/simslim/cmd/simslim@latest
 ```
 
-macOS only, and you need Xcode with an iOS, tvOS, or watchOS Simulator runtime,
-since simslim drives simulators through `xcrun simctl`.
+macOS only, and you need Xcode with an iOS, tvOS, watchOS, or visionOS Simulator
+runtime, since simslim drives simulators through `xcrun simctl`.
 
-All three platforms use the same commands and service profiles. `list`, `top`,
+All four platforms use the same commands and service profiles. `list`, `top`,
 and the macOS app show each device's platform; JSON device records include
-`platform` (`iOS`, `tvOS`, or `watchOS`) alongside the numeric `osVersion`.
-The existing memory figures and category estimates were measured on iOS;
-savings on Apple TV and Apple Watch depend on their runtime and workload.
+`platform` (`iOS`, `tvOS`, `watchOS`, or `visionOS`) alongside the numeric
+`osVersion`. The existing memory figures and category estimates were measured on
+iOS; savings on Apple TV, Apple Watch, and Apple Vision Pro depend on their
+runtime and workload.
 The profile is an allowlist of disable overrides, so labels absent from a
 particular runtime do not represent running processes or additional savings.
 watchOS keeps `com.apple.homed` enabled because it re-enables the service after
 startup; profile verification and managed totals account for this exception.
+visionOS keeps `com.apple.mobileassetd` enabled: the simulated surroundings
+are mobile assets, and without it the simulator boots into a black space
+around the Home View, although apps still launch. A visionOS simulator stays
+expensive even when slim, because rendering its surroundings keeps
+`backboardd` busy.
 For Watch connectivity tests, keep `connectivity,messaging`; for HealthKit or
 fitness tests, also keep `health`, for example:
 
@@ -247,6 +253,12 @@ each daemon and then boots it out of launchd, so the process stops now and
 cannot respawn, with no shutdown/boot cycle. It takes the same
 `--profile`/`--except`/`--keep` selection as `on`.
 
+Most daemons are stopped together: one `launchctl unload -w` with the job plists
+from the runtime writes the same disable override and removes the running job,
+so a busy host does not pay for two `launchctl` spawns per daemon. The result is
+read back, and any daemon still enabled or loaded is then disabled and booted out
+on its own.
+
 ```sh
 simslim on <udid> --no-reboot --profile ci.json
 ```
@@ -364,10 +376,10 @@ Applying a profile normally costs no `launchctl` call at all: the overrides are
 
 The earliest runtime with verified persistence is iOS 18.5. iOS 17.x and 18.3
 accept each `launchctl disable`, but the simulator comes back stock after a
-reboot. The persistent-slimming version gate is iOS/tvOS 18.5 or watchOS 11.5
-and newer. The tvOS and watchOS cutoffs follow the corresponding iOS release
-generation; they are not independent measurements of the earliest persistent
-runtime. `simslim on` rejects older versions before booting or changing launchd
+reboot. The persistent-slimming version gate is iOS/tvOS 18.5, watchOS 11.5, or
+visionOS 2.5 and newer. The tvOS, watchOS, and visionOS cutoffs follow the
+corresponding iOS release generation; they are not independent measurements of
+the earliest persistent runtime. `simslim on` rejects older versions before booting or changing launchd
 state and points at `--no-reboot`, which slims the current boot session only
 (see [Slimming without a reboot](#slimming-without-a-reboot)). Every platform is
 read back after boot, and the command fails instead of claiming success if any

cmd/simslim/main.go

@@ -949,7 +949,7 @@ func fatal(msg string) {
 }
 
 func usage() {
-	fmt.Print(`simslim runs more iOS, tvOS, and watchOS simulators on the same Mac by disabling the
+	fmt.Print(`simslim runs more iOS, tvOS, watchOS, and visionOS simulators on the same Mac by disabling the
 background daemons a simulator does not need.
 
 USAGE

gui/AppModel.swift

@@ -93,8 +93,10 @@ final class AppModel: ObservableObject {
   func disabledDaemonCount(for device: SimulatorDevice) -> Int {
     let allLabels = categories.reduce(into: Set<String>()) { $0.formUnion($1.labels) }
     var disabled = allLabels.subtracting(effectiveKeptLabels)
-    // Keep in sync with Profile.DesiredForDevice: watchOS re-enables homed.
+    // Keep in sync with Profile.DesiredForDevice: watchOS re-enables homed, and
+    // visionOS needs mobileassetd for its surroundings.
     if device.platform == "watchOS" { disabled.remove("com.apple.homed") }
+    if device.platform == "visionOS" { disabled.remove("com.apple.mobileassetd") }
     return disabled.count
   }
 

gui/ContentView.swift

@@ -321,7 +321,7 @@ struct ContentView: View {
               systemImage: "rectangle.slash",
               description: Text(
                 searchText.isEmpty
-                  ? "Install an iOS, tvOS, or watchOS Simulator runtime in Xcode."
+                  ? "Install an iOS, tvOS, watchOS, or visionOS Simulator runtime in Xcode."
                   : "Try a different name, UDID, or OS version.")
             )
             .frame(width: geometry.size.width, height: geometry.size.height)
@@ -791,7 +791,7 @@ private struct ProfileSidebar: View {
           .font(.subheadline.weight(.semibold))
           .foregroundStyle(.green)
         Text(
-          "Core workflow and deadlock-prone daemons are never disabled. HomeKit’s homed service stays enabled on watchOS."
+          "Core workflow and deadlock-prone daemons are never disabled. HomeKit’s homed stays enabled on watchOS, and the asset service mobileassetd on visionOS."
         )
         .font(.caption)
         .foregroundStyle(.secondary)

gui/Models.swift

@@ -26,6 +26,7 @@ struct SimulatorDevice: Decodable, Identifiable, Equatable {
     switch platform {
     case "tvOS": return "appletv"
     case "watchOS": return "applewatch"
+    case "visionOS": return "visionpro"
     default: return "iphone"
     }
   }

launchd_batch.go

@@ -0,0 +1,100 @@
+package simslim
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+// launchdJobDirs are the RuntimeRoot directories holding the job plists that
+// launchd_sim bootstraps into the simulator's system domain.
+var launchdJobDirs = []string{"System/Library/LaunchDaemons", "System/Library/LaunchAgents"}
+
+// unloadChunk bounds how many plist paths go into one `launchctl unload`, so
+// the argument list stays far below ARG_MAX however long the profile grows.
+const unloadChunk = 64
+
+func parseRuntimeRoot(out []byte, runtimeID string) (string, error) {
+	var parsed struct {
+		Runtimes []struct {
+			Identifier  string `json:"identifier"`
+			RuntimeRoot string `json:"runtimeRoot"`
+		} `json:"runtimes"`
+	}
+	if err := json.Unmarshal(out, &parsed); err != nil {
+		return "", fmt.Errorf("parse simctl list runtimes: %w", err)
+	}
+	for _, r := range parsed.Runtimes {
+		if r.Identifier == runtimeID && r.RuntimeRoot != "" {
+			return r.RuntimeRoot, nil
+		}
+	}
+	return "", fmt.Errorf("runtime %s has no runtimeRoot", runtimeID)
+}
+
+// launchdJobPlists maps each label to the job plist that defines exactly that
+// label. A plist is only used when its own Label key matches, so a renamed or
+// shared file can never unload a daemon outside the allowlist; labels without
+// a matching plist are left for the per-label path.
+func launchdJobPlists(ctx context.Context, root string, labels []string, plistLabel func(context.Context, string) (string, error)) map[string]string {
+	paths := make(map[string]string, len(labels))
+	for _, label := range labels {
+		if ctx.Err() != nil {
+			break
+		}
+		for _, dir := range launchdJobDirs {
+			path := filepath.Join(root, dir, label+".plist")
+			if _, err := os.Stat(path); err != nil {
+				continue
+			}
+			if got, err := plistLabel(ctx, path); err == nil && got == label {
+				paths[label] = path
+				break
+			}
+		}
+	}
+	return paths
+}
+
+// readPlistLabel reads a job plist's Label with the host's plutil, which
+// handles both XML and binary plists.
+func readPlistLabel(ctx context.Context, path string) (string, error) {
+	out, err := exec.CommandContext(ctx, "plutil", "-extract", "Label", "raw", "-o", "-", path).Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(out)), nil
+}
+
+// parseLaunchctlList reads `launchctl list` rows: "PID<TAB>Status<TAB>Label",
+// with "-" as the PID of a loaded job that is not running.
+func parseLaunchctlList(output string) map[string]bool {
+	loaded := map[string]bool{}
+	for _, line := range strings.Split(output, "\n") {
+		fields := strings.Fields(line)
+		if len(fields) != 3 || fields[2] == "Label" {
+			continue
+		}
+		loaded[fields[2]] = true
+	}
+	return loaded
+}
+
+// stillToStop keeps the labels the batch did not finish: no disable override
+// yet, or still loaded. A few jobs stay listed even with their override in
+// place (on a slim visionOS 27.0 simulator, for example siri.context.service
+// and TrustedPeersHelper), so they always take the per-label bootout; the old
+// path booted out every label, so this is never more work than before.
+func stillToStop(labels []string, disabled, loaded map[string]bool) []string {
+	var rest []string
+	for _, l := range labels {
+		if !disabled[l] || loaded[l] {
+			rest = append(rest, l)
+		}
+	}
+	return rest
+}