docs(linux): park Slice L at L1 checkpoint

AGENTS.md

@@ -390,7 +390,8 @@ scheduler cadence, and every resource dimension inside its ceiling. SIGINT
 produced ACE-confirmed graceful logout for both accounts and a passing final
 `disposed` sample: two converged Runtime roots, zero entities/inventory/host
 or content leases, and disposed shared content. K4 and Slice K are closed;
-Slice L Linux graphical/platform work is active. L0 completed at `66f114b2`:
+Slice L Linux graphical/platform work is parked at its L1 implementation
+checkpoint by user direction on 2026-07-27. L0 completed at `66f114b2`:
 `ApplicationPathSet` is the shared XDG/Windows path authority;
 `GraphicalHostPlatformServices` owns one OS/architecture/RID, native manifest,
 and frame-waiter factory; Linux uses an absolute `CLOCK_MONOTONIC` wait;
@@ -400,7 +401,16 @@ Ubuntu graphical CI/package gate pass. Windows passes 415 Runtime, 67
 Headless, 543 UI, and 3,736 App tests / 3 skips; the complete Release suite
 passes 8,799 / 5 skips. Native Ubuntu passes the portable closure, 14 L0 App
 tests, and exact `linux-x64` publish. L1 context/extension/native-backend
-validation is next.
+validation implementation landed at `11501d52`: immutable
+Win32/X11/Wayland selection, packaged GLFW 3.4 preference, atomic capability
+reporting, and active bindless/draw-parameters/MDI/SSBO/timer/FBO/persistent-
+buffer probes now gate renderer construction. Native Windows AMD passes every
+active probe and terminal graphical/audio ownership converges to zero. WSLg
+X11/Wayland correctly reject Mesa D3D12/llvmpipe because mandatory
+`GL_ARB_bindless_texture` is absent. App tests pass 3,763 / 3 skips and the
+complete Release suite passes 8,826 / 5 skips. A supported physical Linux
+AMD/NVIDIA driver row remains the first gate when work resumes; that gate and
+L2–L6 are deferred.
 J0's rollback is
 `git revert b632672e5ccabfb44c551e08f1c411ab2669c44a`.
 J1's rollback is
@@ -474,6 +484,8 @@ K4's current rollbacks, newest first, are
 `git revert cb512fd0916fbf49285c9b64df1630c5a69a0d20`.
 L0's rollback is
 `git revert 66f114b258c0c37b51a7c0e04ca0d6441f4b1699`.
+L1's implementation-checkpoint rollback is
+`git revert 11501d52cad942850d88f83490710faf1d5cdf28`.
 Slice H's retained UI/frame, bounded-light, and pooled/borrowed/direct network
 work is complete; the exact seven-checkpoint connected lifecycle/reconnect gate
 passes. Slice I is closed in
@@ -509,7 +521,9 @@ closeout is
 closed in `docs/plans/2026-07-26-modern-runtime-slice-k.md`; K4 evidence is
 `docs/research/2026-07-27-slice-k4-resource-telemetry-checkpoint.md`; Slice L
 executes from `docs/plans/2026-07-26-modern-runtime-slice-l.md`; L0 evidence is
-`docs/research/2026-07-27-slice-l0-platform-services.md`. The exact G4 visual
+`docs/research/2026-07-27-slice-l0-platform-services.md`; L1 checkpoint
+evidence is
+`docs/research/2026-07-27-slice-l1-graphical-capability-checkpoint.md`. The exact G4 visual
 rollback
 is `git revert ef1d263337997bb030eadb7b8e71d73dc659907a`; do not revert G3 or
 the portal-warmup corrections. Evidence:

CLAUDE.md

@@ -388,7 +388,8 @@ scheduler cadence, and every resource dimension inside its ceiling. SIGINT
 produced ACE-confirmed graceful logout for both accounts and a passing final
 `disposed` sample: two converged Runtime roots, zero entities/inventory/host
 or content leases, and disposed shared content. K4 and Slice K are closed;
-Slice L Linux graphical/platform work is active. L0 completed at `66f114b2`:
+Slice L Linux graphical/platform work is parked at its L1 implementation
+checkpoint by user direction on 2026-07-27. L0 completed at `66f114b2`:
 `ApplicationPathSet` is the shared XDG/Windows path authority;
 `GraphicalHostPlatformServices` owns one OS/architecture/RID, native manifest,
 and frame-waiter factory; Linux uses an absolute `CLOCK_MONOTONIC` wait;
@@ -398,7 +399,16 @@ Ubuntu graphical CI/package gate pass. Windows passes 415 Runtime, 67
 Headless, 543 UI, and 3,736 App tests / 3 skips; the complete Release suite
 passes 8,799 / 5 skips. Native Ubuntu passes the portable closure, 14 L0 App
 tests, and exact `linux-x64` publish. L1 context/extension/native-backend
-validation is next.
+validation implementation landed at `11501d52`: immutable
+Win32/X11/Wayland selection, packaged GLFW 3.4 preference, atomic capability
+reporting, and active bindless/draw-parameters/MDI/SSBO/timer/FBO/persistent-
+buffer probes now gate renderer construction. Native Windows AMD passes every
+active probe and terminal graphical/audio ownership converges to zero. WSLg
+X11/Wayland correctly reject Mesa D3D12/llvmpipe because mandatory
+`GL_ARB_bindless_texture` is absent. App tests pass 3,763 / 3 skips and the
+complete Release suite passes 8,826 / 5 skips. A supported physical Linux
+AMD/NVIDIA driver row remains the first gate when work resumes; that gate and
+L2–L6 are deferred.
 J0's rollback is
 `git revert b632672e5ccabfb44c551e08f1c411ab2669c44a`.
 J1's rollback is
@@ -472,6 +482,8 @@ K4's current rollbacks, newest first, are
 `git revert cb512fd0916fbf49285c9b64df1630c5a69a0d20`.
 L0's rollback is
 `git revert 66f114b258c0c37b51a7c0e04ca0d6441f4b1699`.
+L1's implementation-checkpoint rollback is
+`git revert 11501d52cad942850d88f83490710faf1d5cdf28`.
 Slice H's retained UI/frame, bounded-light, and pooled/borrowed/direct network
 work is complete; the exact seven-checkpoint connected lifecycle/reconnect gate
 passes. Slice I is closed in
@@ -507,7 +519,9 @@ closeout is
 closed in `docs/plans/2026-07-26-modern-runtime-slice-k.md`; K4 evidence is
 `docs/research/2026-07-27-slice-k4-resource-telemetry-checkpoint.md`; Slice L
 executes from `docs/plans/2026-07-26-modern-runtime-slice-l.md`; L0 evidence is
-`docs/research/2026-07-27-slice-l0-platform-services.md`. The exact G4 visual
+`docs/research/2026-07-27-slice-l0-platform-services.md`; L1 checkpoint
+evidence is
+`docs/research/2026-07-27-slice-l1-graphical-capability-checkpoint.md`. The exact G4 visual
 rollback
 is `git revert ef1d263337997bb030eadb7b8e71d73dc659907a`; do not revert G3 or
 the portal-warmup corrections. Evidence:

docs/architecture/acdream-architecture.md

@@ -272,6 +272,13 @@ src/
     Platform/
       GraphicalHostPlatformServices.cs -> one startup OS/architecture/RID,
                                           native-manifest, path, pacing owner
+      GraphicalWindowBackendSelection.cs -> immutable GLFW 3.4
+                                             Win32/X11/Wayland selection and
+                                             packaged-native preference
+      GraphicalCapabilityRecord.cs -> pre-render platform/GL/audio/input
+                                      capability report and startup guard
+      GraphicalGlFunctionProbe.cs -> active modern-GL shader/MDI/SSBO/
+                                     timer/FBO/persistent-buffer validation
       GraphicalLegacyConfigurationMigrator.cs -> no-overwrite Windows
                                                   LocalAppData migration
     Physics/

docs/plans/2026-04-11-roadmap.md

@@ -1,13 +1,18 @@
 # acdream — strategic roadmap
 
-**Status:** Living document. Updated 2026-07-27. **M3 landed; M4 is active.** M3's retail casting/UI, R6 locomotion/collision/projectile/teleport/radar rebaseline, deterministic fresh-login/portal world lifecycle, and final two-client portal observer flow are user-gated. All eight slices of the behavior-preserving ownership campaign in [`docs/architecture/code-structure.md`](../architecture/code-structure.md), their automated closeout, and the user's connected visual matrix are complete. Modern Runtime J3 canonical entity/object lifetime and J4 gameplay-state ownership are closed at `89e6b207`; J5.1 canonical selection/combat/target-mode ownership is closed at `b298f99f`, J5.2 interaction transactions at `f5f7b417`, J5.3 combat/magic intent at `20df9d15`, J5.4 local movement/outbound cadence at `aa3f4a60`, J5.5 per-session physics/remote simulation at `7e6033d0`, J5.6 projectile simulation at `2aee3356`, and J5.7 combined simulation closeout at `cdee7a4b`. J6.1 world-environment ownership is closed at `902076c0`; J6.2 canonical reveal generation and typed destination readiness is closed at `a6860d55` plus `acb845d8`; J6.3 exact F751/Position destination correlation is closed at `6a063a27`; J6.4 exact graphical-host acknowledgement and owner cleanup is closed at `18d17d8b`. J7's one graphical `GameRuntime` root is closed at `ce41efb9`, including the user's 2026-07-27 exact post-cutover visual acceptance. J8 closed Slice J at `a9a822f2` with one shared graphical/no-window root and generation-reset transaction. Slice K Linux headless/multi-session work is closed. K0's tested no-presentation Windows/Linux boundary closed at `aada8a37`, K1's portable single-session host at `f8cb840f`, K2's deterministic scheduler and shared bot API at `7e8acb74` plus `38e83640`, and K3's shared-content/isolation plus connected observer gate at `3f340125`. K4 closed through `776482da`: 1/5/10/30-root isolation and two-hour simulated endurance, death/randomized cancellation, committed resource ceilings, ten minutes of exact native Linux two-account connected sampling, ACE-confirmed graceful logout, and zero-debt Runtime/content convergence all pass. Slice L Linux graphical/platform work is active. Issue #225's lifestone/particle alpha comparison remains a separate rendering visual gate.
+**Status:** Living document. Updated 2026-07-27. **M3 landed; M4 is active.** M3's retail casting/UI, R6 locomotion/collision/projectile/teleport/radar rebaseline, deterministic fresh-login/portal world lifecycle, and final two-client portal observer flow are user-gated. All eight slices of the behavior-preserving ownership campaign in [`docs/architecture/code-structure.md`](../architecture/code-structure.md), their automated closeout, and the user's connected visual matrix are complete. Modern Runtime J3 canonical entity/object lifetime and J4 gameplay-state ownership are closed at `89e6b207`; J5.1 canonical selection/combat/target-mode ownership is closed at `b298f99f`, J5.2 interaction transactions at `f5f7b417`, J5.3 combat/magic intent at `20df9d15`, J5.4 local movement/outbound cadence at `aa3f4a60`, J5.5 per-session physics/remote simulation at `7e6033d0`, J5.6 projectile simulation at `2aee3356`, and J5.7 combined simulation closeout at `cdee7a4b`. J6.1 world-environment ownership is closed at `902076c0`; J6.2 canonical reveal generation and typed destination readiness is closed at `a6860d55` plus `acb845d8`; J6.3 exact F751/Position destination correlation is closed at `6a063a27`; J6.4 exact graphical-host acknowledgement and owner cleanup is closed at `18d17d8b`. J7's one graphical `GameRuntime` root is closed at `ce41efb9`, including the user's 2026-07-27 exact post-cutover visual acceptance. J8 closed Slice J at `a9a822f2` with one shared graphical/no-window root and generation-reset transaction. Slice K Linux headless/multi-session work is closed. K0's tested no-presentation Windows/Linux boundary closed at `aada8a37`, K1's portable single-session host at `f8cb840f`, K2's deterministic scheduler and shared bot API at `7e8acb74` plus `38e83640`, and K3's shared-content/isolation plus connected observer gate at `3f340125`. K4 closed through `776482da`: 1/5/10/30-root isolation and two-hour simulated endurance, death/randomized cancellation, committed resource ceilings, ten minutes of exact native Linux two-account connected sampling, ACE-confirmed graceful logout, and zero-debt Runtime/content convergence all pass. Slice L Linux graphical/platform work is parked at its L1 implementation checkpoint by user direction on 2026-07-27. Issue #225's lifestone/particle alpha comparison remains a separate rendering visual gate.
 **Purpose:** One source of truth for where the project is and where it's going. Every observed defect or missing feature has a named phase that owns it; when something looks wrong in-game, look here to find the phase that'll address it. Implementation details live in per-phase specs under `docs/superpowers/specs/`, not in this file.
 
 **Slice L checkpoint:** L0 closed at `66f114b2` with one typed graphical
 platform/native manifest, shared XDG/Windows paths, factory-selected
 Windows/Linux frame waits, portable persistence/plugin discovery, RID-safe
-App publish, and an Ubuntu graphical CI/package gate. Slice L1
+App publish, and an Ubuntu graphical CI/package gate. L1's implementation
-context/extension/native-backend validation is active.
+checkpoint landed at `11501d52`: immutable Win32/X11/Wayland selection,
+packaged GLFW 3.4 preference, atomic capability reporting, and active modern-GL
+probes gate renderer construction. Native Windows passes. WSLg X11/Wayland
+correctly report that Mesa D3D12/llvmpipe lacks mandatory bindless textures.
+A supported physical Linux AMD/NVIDIA driver row remains the first gate when
+Slice L resumes; the physical gate and L2–L6 are deferred.
 
 ---
 
@@ -1822,7 +1827,11 @@ port in any phase — no separate listing here.
 > Headless tests pass 67/67 and the complete Release suite passes 8,784 / 5
 > skips. The exact two-account connected soak then passed 20 periodic samples,
 > ACE-confirmed graceful logout, and a zero-debt `disposed` record. Slice K is
-> closed. Slice L0 completed at `66f114b2`; L1 is active.
+> closed. Slice L0 completed at `66f114b2`; L1's implementation checkpoint
+> landed at `11501d52`. Native Windows passes every active capability and
+> shutdown probe; WSLg X11/Wayland correctly fail the mandatory bindless
+> requirement. By user direction on 2026-07-27, the supported physical Linux
+> driver row and L2–L6 are deferred; resume at that physical gate.
 > The historical exact cutover
 > rollback remains
 > `git revert ef1d263337997bb030eadb7b8e71d73dc659907a`. Slice H is complete:
@@ -1869,7 +1878,11 @@ hitch and follows.
 > no-window Linux host and approximately 30-session target from
 > [`2026-07-26-modern-runtime-slice-k.md`](2026-07-26-modern-runtime-slice-k.md);
 > Slice L executes the graphical Linux/platform work. K0-K4 and Slice K are
-> complete through `776482da`. L0 is complete at `66f114b2`; L1 is active.
+> complete through `776482da`. L0 is complete at `66f114b2`; L1's
+> implementation checkpoint is `11501d52`, with native Windows positive and
+> WSLg X11/Wayland negative capability rows recorded. A supported physical
+> Linux AMD/NVIDIA row and L2–L6 are deferred by user direction; resume at the
+> physical L1 gate.
 > K's automated 1/5/10/30-root
 > isolation, two-hour simulated endurance, death/cancellation, and committed
 > resource-envelope gates pass; the exact two-account connected process added

docs/plans/2026-05-12-milestones.md

@@ -316,7 +316,8 @@ residency is `0/0/0` at every stable checkpoint and teardown converges. Slice I
   dimension inside its ceiling. SIGINT then produced ACE-confirmed graceful
   logout for both accounts and a passing `disposed` record with two converged
   Runtime roots, zero entities/inventory/host/content leases, and disposed
-  shared content. K4 and Slice K are closed; Slice L is active.
+  shared content. K4 and Slice K are closed; Slice L is parked at its L1
+  implementation checkpoint by user direction on 2026-07-27.
   L0 completed at `66f114b2`: one startup-owned graphical platform/native
   manifest, the shared Runtime XDG/Windows path set, factory-selected Windows
   and absolute-monotonic Linux frame waits, portable settings/keybindings/
@@ -325,8 +326,17 @@ residency is `0/0/0` at every stable checkpoint and teardown converges. Slice I
   3,736 App tests / 3 skips; the complete Release suite passes 8,799 / 5
   skips. Native Ubuntu passes the portable Runtime/Headless/UI and 14 L0 App
   tests, and the exact `linux-x64` package contains resolved GLFW, OpenAL
-  Soft, cimgui, shaders, and smoke plugin. Slice L1 context/extension/native-
+  Soft, cimgui, shaders, and smoke plugin. Slice L1's implementation checkpoint
-  backend validation is next.
+  landed at `11501d52`: immutable Win32/X11/Wayland backend selection,
+  packaged GLFW 3.4 preference, atomic capability reporting, and active
+  bindless/draw-parameters/MDI/SSBO/timer/FBO/persistent-buffer probes now
+  reject unsupported contexts before renderer construction. The native
+  Windows AMD gate passes all probes and completes graphical/audio teardown;
+  WSLg X11 and Wayland correctly reject its Mesa D3D12/llvmpipe contexts
+  because `GL_ARB_bindless_texture` is absent. App tests pass 3,763 / 3 skips
+  and the complete Release suite passes 8,826 / 5 skips. A supported physical
+  Linux AMD/NVIDIA driver row remains mandatory when Slice L resumes; its
+  physical gate and L2–L6 are deferred.
 Slice-I closeout evidence is
 [`../research/2026-07-25-slice-i7-closeout.md`](../research/2026-07-25-slice-i7-closeout.md).
 Slice-J2 closeout evidence is

docs/plans/2026-07-26-modern-runtime-slice-l.md

@@ -1,6 +1,7 @@
 # Modern runtime Slice L — Linux graphical host and evidence-gated GPU work
 
-**Status:** ACTIVE — L0 COMPLETE; L1 NEXT
+**Status:** DEFERRED 2026-07-27 — L0 COMPLETE; L1 IMPLEMENTATION CHECKPOINT
+COMPLETE; PHYSICAL-LINUX DRIVER GATE AND L2–L6 PARKED
 **Parent:** `2026-07-24-modern-runtime-architecture.md`, Slice L
 **Authorization:** the user approved Slices F–L on 2026-07-24
 **Purpose:** ship the existing modern OpenGL client on supported Linux drivers
@@ -177,6 +178,18 @@ frame waiters and portable paths; no Windows P/Invoke executes on Linux.
 
 ### L1 — context, extensions, and native backends
 
+**Implementation checkpoint at `11501d52` (2026-07-27).** The exact packaged
+GLFW 3.4 backend is selected before window creation; X11/Wayland choice,
+complete passive capabilities, active modern-GL calls, optional OpenAL smoke,
+atomic reports, actionable exit 4, and zero-debt successful/rejected Studio
+shutdown are implemented. Windows AMD passes the supported smoke. WSLg X11,
+Wayland, and AMD D3D12 paths correctly reject only missing
+`GL_ARB_bindless_texture`. These are negative rows. At the user's direction on
+2026-07-27, physical Mesa/RadeonSI/NVIDIA supported-driver evidence and L2–L6
+are deferred; when Slice L resumes, that physical gate remains first and L2
+must not begin before it passes. Exact evidence is
+[`../research/2026-07-27-slice-l1-graphical-capability-checkpoint.md`](../research/2026-07-27-slice-l1-graphical-capability-checkpoint.md).
+
 - Create a Linux window and OpenGL 4.3 core context under X11 and Wayland.
 - Capture the full capability record before renderer construction.
 - Verify mandatory bindless and shader-draw-parameter calls, MDI, SSBOs,
@@ -304,3 +317,15 @@ exact `git revert <sha>` after each focused/Linux/Windows/connected/visual
 gate. GPU candidates each receive their own plan, commit, measurement, visual
 gate, and rollback; rejected experiments are reverted rather than hidden
 behind dormant alternate paths.
+
+L0 rollback:
+
+```text
+git revert 66f114b258c0c37b51a7c0e04ca0d6441f4b1699
+```
+
+L1 implementation-checkpoint rollback:
+
+```text
+git revert 11501d52cad942850d88f83490710faf1d5cdf28
+```

docs/research/2026-07-27-slice-l1-graphical-capability-checkpoint.md

@@ -0,0 +1,122 @@
+# Slice L1 graphical capability checkpoint
+
+**Date:** 2026-07-27
+**Production commit:** `11501d52cad942850d88f83490710faf1d5cdf28`
+**Status:** implementation complete; further Linux graphical work deferred by
+the user on 2026-07-27. The supported physical-Linux driver matrix remains the
+first gate when Slice L resumes.
+
+## Scope
+
+This checkpoint establishes the Linux/Windows graphical startup oracle before
+renderer construction. It does not add a renderer fallback and does not change
+gameplay or visual behavior.
+
+`GraphicalHostPlatformServices` now owns an immutable GLFW backend selection.
+`ACDREAM_DISPLAY_PROTOCOL=auto|x11|wayland` is consumed once before
+`Window.Create`. The platform owner configures the exact
+`GlfwProvider.UninitializedGLFW` instance used by Silk's window backend.
+
+Silk 2.23 asks for `libglfw.so.3.3`, while its packaged multi-backend GLFW 3.4
+asset is `libglfw.so.3`. The default native search order previously selected
+Ubuntu's machine-global GLFW 3.3 before reaching the packaged 3.4 library.
+Startup now prioritizes the application directory inside Silk's path resolver,
+so X11/Wayland selection and package provenance are deterministic.
+
+Before any renderer object is created, the client records:
+
+- OS, RID, requested and active display protocol, GLFW backend/version;
+- GL vendor, renderer, version, GLSL, context flags/profile, limits, and every
+  extension;
+- default framebuffer color/depth/stencil/MSAA/sRGB facts;
+- window, monitor, refresh, framebuffer/logical size, and input-device facts;
+- audio request/availability/playback/disposal state;
+- window/GL/input/audio ownership and terminal shutdown state.
+
+Advertisement is not treated as proof. A balanced active probe executes:
+
+- bindless texture handle, resident, and non-resident calls;
+- a shader using `gl_DrawIDARB`/`gl_BaseInstanceARB` plus MDI;
+- SSBO allocation and binding;
+- a timer query;
+- an sRGB color plus depth/stencil framebuffer;
+- persistent coherent mapping whenever buffer storage is advertised.
+
+Unsupported hardware receives one actionable report and exit code 4. The
+Studio smoke defers native close until after `RenderStack.EndFrame`, so both
+successful and rejected startup release every owned context resource before
+the final report is atomically rewritten.
+
+## Positive supported gate
+
+Windows 11 Pro build 26200, AMD Radeon RX 9070 XT, driver
+`32.0.31021.5001`:
+
+- GLFW `3.4.0 Win32 WGL`;
+- OpenGL `4.3.0 Core Profile Context 26.6.4.260624`;
+- 240 Hz monitor, 1280 x 720 logical/framebuffer smoke;
+- bindless, shader draw parameters, MDI, SSBO, timer query, sRGB
+  depth/stencil, and persistent coherent storage all actively pass;
+- OpenAL Soft default device opens, accepts the 50 ms smoke wave, and disposes;
+- the 1280 x 720 retained-UI mockup screenshot is visually intact;
+- process exits 0 with zero owned window, GL, input, and audio resources and
+  `ShutdownComplete=true`.
+
+## Linux backend and negative-capability gates
+
+Package: exact framework-dependent `linux-x64` publish of
+`11501d52cad942850d88f83490710faf1d5cdf28`.
+
+Host: Ubuntu 24.04.3 LTS under WSL2 kernel
+`6.6.87.2-microsoft-standard-WSL2`, WSLg X11 and Wayland endpoints.
+
+Both explicit backends create an OpenGL 4.5 core context, expose one keyboard
+and one mouse, capture their framebuffer/monitor facts, and identify the
+packaged multi-backend GLFW 3.4:
+
+| Protocol | Monitor | Renderer | Result |
+|---|---|---|---|
+| X11 | `XWAYLAND0`, 60 Hz | Mesa llvmpipe 25.2.8 | exit 4: bindless absent |
+| Wayland | `weston rdp`, 60 Hz | Mesa llvmpipe 25.2.8 | exit 4: bindless absent |
+| X11 + `GALLIUM_DRIVER=d3d12` | `XWAYLAND0`, 60 Hz | D3D12 (AMD Radeon RX 9070 XT), GL 4.6 | exit 4: bindless absent |
+
+Each final report names only `GL_ARB_bindless_texture` as the mandatory
+missing feature, preserves the complete capability record, and reports zero
+window/GL/input/audio ownership with `ShutdownComplete=true`. This is the
+intended mandatory-modern-renderer failure, not an accepted Linux driver row.
+
+The Ubuntu graphical CI job now builds/publishes the App, runs the focused
+platform/capability tests, checks the native package closure, and verifies the
+same actionable X11 software-driver rejection under Xvfb.
+
+## Automated gates
+
+- graphical backend/capability/Studio focused tests: 29/29;
+- App Release tests: 3,763 passed / 3 skipped;
+- complete Release solution: 8,826 passed / 5 skipped;
+- Release solution build: zero warnings and zero errors;
+- Windows supported smoke: exit 0, screenshot present, all function probes
+  pass, audio playback submitted, all terminal ledgers zero;
+- WSLg X11 and Wayland negative gates: exit 4, exact bindless diagnostic,
+  all terminal ledgers zero;
+- concurrent two-account Linux headless process remained 2/2 in-world with
+  zero faults/reconnects/resource-envelope violations throughout the gates.
+
+## Deferred L1 acceptance
+
+Do not claim Linux graphical support from WSLg. L1 still requires at least one
+physical supported Linux row and the committed driver matrix:
+
+- AMD Mesa/RadeonSI X11 and Wayland;
+- NVIDIA proprietary X11 and supported Wayland;
+- Intel only when every mandatory capability is present.
+
+On each supported row, rerun the packaged screenshot/input/audio/teardown
+smoke. Only then close L1 and begin the connected L2 route. This work and
+Slices L2–L6 were explicitly parked by the user on 2026-07-27.
+
+## Rollback
+
+```text
+git revert 11501d52cad942850d88f83490710faf1d5cdf28
+```

memory/project_linux_graphical.md

@@ -4,6 +4,8 @@
 
 Slice L0 completed at
 `66f114b258c0c37b51a7c0e04ca0d6441f4b1699`.
+Slice L1's implementation checkpoint landed at
+`11501d52cad942850d88f83490710faf1d5cdf28`.
 
 The same `AcDream.App` now builds and publishes for `linux-x64`; there is no
 Linux gameplay or renderer fork.
@@ -44,22 +46,51 @@ Rollback:
 git revert 66f114b258c0c37b51a7c0e04ca0d6441f4b1699
 ```
 
-## Next work — L1
+## L1 implementation checkpoint
 
-Do not claim Linux graphical support merely from publish success. L1 must:
+Canonical seams:
 
-1. start the exact package under the available X11 and Wayland sessions;
+- `ACDREAM_DISPLAY_PROTOCOL=auto|x11|wayland` selects one immutable backend
-2. capture OS/display/compositor/GPU/driver/OpenGL vendor, renderer, version,
+  before `Window.Create`.
-   mandatory extensions, swap interval, refresh, DPI, and audio backend before
+- `GraphicalWindowBackendSelection` configures Silk's exact GLFW backend and
-   renderer construction;
+  makes the packaged GLFW 3.4 native library win over older system installs.
-3. create the OpenGL 4.3 core context and reject missing bindless texture or
+- `GraphicalCapabilityRecord` captures platform, RID, display protocol, GL
-   shader draw parameters with one actionable report;
+  identity/extensions/limits, framebuffer, input/window, audio, and terminal
-4. validate GLFW window/input callbacks, relative mouse/focus, framebuffer
+  ownership into one atomic report.
-   sizing, clipboard, and monitor facts;
+- `GraphicalGlFunctionProbe` actively validates bindless texture,
-5. initialize OpenAL fail-open exactly as current Windows behavior permits;
+  draw-parameters plus MDI, SSBO, timer query, sRGB/depth/stencil FBO, and
-6. render a packaged smoke scene, capture a screenshot, and close with zero
+  persistent coherent buffer behavior before renderer construction.
-   GL/OpenAL/window debt.
+- Unsupported contexts exit with code 4 and a precise report. No legacy
+  renderer or fabricated fallback is introduced.
+- Studio screenshot shutdown is deferred until the completed render frame;
+  accepted and rejected startup paths both report zero terminal ownership.
 
-Historical test-only issue: two installed-DAT App tests still hard-code
+Evidence:
-`C:\Turbine\Asheron's Call`. They are not production blockers, but clean them
+
-before claiming the complete App test suite on a clean Linux runner.
+- native Windows 11 + AMD Radeon RX 9070 XT: every active GL probe passes,
+  OpenAL submits playback and disposes, the packaged smoke frame is intact,
+  and terminal ownership is zero;
+- WSLg X11 and Wayland: packaged GLFW 3.4 and protocol selection are correct,
+  but llvmpipe lacks mandatory `GL_ARB_bindless_texture`;
+- WSLg with `GALLIUM_DRIVER=d3d12` reaches the AMD GPU and OpenGL 4.6, but
+  still lacks mandatory `GL_ARB_bindless_texture`; this is a WSLg/Mesa
+  capability limit, not an acdream package-resolution defect;
+- App tests pass 3,763 / 3 skips; the complete Release suite passes
+  8,826 / 5 skips;
+- checkpoint:
+  `docs/research/2026-07-27-slice-l1-graphical-capability-checkpoint.md`.
+
+Rollback:
+
+```text
+git revert 11501d52cad942850d88f83490710faf1d5cdf28
+```
+
+## Deferred continuation
+
+Do not claim native Linux graphical support from WSLg. Run the exact
+`linux-x64` package on a physical Linux AMD RadeonSI or supported NVIDIA
+driver under the available X11/Wayland sessions. It must pass the same
+capability report, packaged smoke frame, input/window/audio checks, and
+zero-debt shutdown. The user deferred this physical-driver gate and Slices
+L2–L6 on 2026-07-27. L2 has not started; resume at the physical L1 gate.

memory/project_modern_runtime_headless.md

@@ -67,16 +67,16 @@ for both accounts. The final `disposed` sample had two converged Runtime roots,
 zero entities/inventory/host/content leases, disposed shared content, and
 `withinCeilings=true`.
 
-## Next work
+## Deferred graphical continuation
 
-Slice L is active under
+Slice L is parked under
 `docs/plans/2026-07-26-modern-runtime-slice-l.md`. L0 completed at
-`66f114b2`: the shared path owner, graphical platform/native manifest,
+`66f114b2`, and L1's immutable backend/capability implementation checkpoint
-factory-selected Linux wait, portable persistence/plugins, RID-safe publish,
+landed at `11501d52`. Native Windows passes; WSLg correctly rejects its missing
-and Ubuntu graphical package gate pass. Continue from
+mandatory bindless-texture capability. By user direction on 2026-07-27,
-`memory/project_linux_graphical.md`; L1 must prove the actual Linux
+physical Linux validation and L2–L6 are deferred. Resume from
-window/context/input/audio lifecycle rather than revisiting headless
+`memory/project_linux_graphical.md` at the physical supported-driver L1 gate;
-ownership.
+do not revisit headless ownership or add a renderer fallback.
 
 Final K3 automated counts: Runtime 412, Headless 47, App 3,722 / 3 skips,
 complete Release 8,764 / 5 skips.