snkmcb · Sep 23, 2026 · Sep 23, 2026 · Sep 23, 2026
diff --git a/backends/physicsJolt/cmake/physicsJoltConfig.cmake.in b/backends/physicsJolt/cmake/physicsJoltConfig.cmake.in
@@ -6,6 +6,7 @@ if(NOT TARGET physicsCore::physicsCore)
 endif()
 @PHYSICSJOLT_FIND_JOLT_DEPENDENCY@
 
+set(physicsJolt_BACKEND_AVAILABLE @PHYSICSJOLT_BACKEND_AVAILABLE@)
 set(_physicsJolt_requires_jolt @PHYSICSJOLT_BACKEND_AVAILABLE@)
 if(_physicsJolt_requires_jolt)
   set(_physicsJolt_jolt_target [==[@PHYSICSJOLT_BACKEND_TARGET@]==])

diff --git a/docs/README.md b/docs/README.md
@@ -4,12 +4,12 @@ Documentation is organized by responsibility. The taxonomy follows
 `usd-mmd-plugins`: design says what is intended, architecture fixes structure,
 reference reports what exists, and the roadmap contains incomplete work.
 
-**Current tree (2026-09-23): Phase 2 backend extraction in progress.** The root
-build, packages, boundary checks, and installed-consumer test exist. Neutral
-rigid transform values, typed handles, validated descriptors, the single-owner
-world contract, optional segment and ground queries, and the initial Jolt
-backend are implemented; its OpenStrata intent passes locally. Hosted backend
-evidence, an OpenUSD bridge, and a release are not. The
+**Current tree (2026-09-23): Phase 2 complete; Phase 3 migration in progress.**
+The root build, packages, boundary checks, and installed-consumer test exist.
+Neutral rigid transform values, typed handles, validated descriptors, the
+single-owner world contract, optional segment and ground queries, and the Jolt
+backend are implemented and pass local and hosted Windows/Linux evidence.
+Stage Runner migration, an OpenUSD bridge, and a release are not complete. The
 [capability matrix](reference/CAPABILITY_MATRIX.md) is the only page that may
 claim implementation status.
 

diff --git a/docs/architecture/PACKAGE_CONTRACT.md b/docs/architecture/PACKAGE_CONTRACT.md
@@ -1,6 +1,6 @@
 # Installed package contract
 
-> **Status: accepted, revised 2026-09-22.** `physicsCore` and `physicsJolt`
+> **Status: accepted, revised 2026-09-23.** `physicsCore` and `physicsJolt`
 > install and pass a clean-prefix consumer test. `physicsCore` now includes
 > neutral values, typed handles, validated descriptors, typed errors, and the
 > single-owner world plus optional segment and ground query interfaces and
@@ -18,7 +18,7 @@ not need this repository's source tree.
 | Package | Imported target | Provides | Planned phase |
 | --- | --- | --- | --- |
 | `physicsCore` | `physicsCore::physicsCore` | Version surface plus neutral vector, quaternion, transform, typed handles, validated box/body/fixed-constraint descriptors, semantic collision filters, typed errors, world lifecycle/state, and optional segment and ground query interfaces | Phase 1 surface present |
-| `physicsJolt` | `physicsJolt::physicsJolt` | `backendAvailable()` plus `createWorld()`; a Jolt-enabled build provides shapes, bodies, fixed constraints, commands, stepping, changed state, segment queries, and ground queries, while a no-Jolt build reports typed unavailability | Phase 2 implementation present; hosted evidence pending |
+| `physicsJolt` | `physicsJolt::physicsJolt` | `physicsJolt_BACKEND_AVAILABLE` package metadata, `backendAvailable()`, and `createWorld()`; a Jolt-enabled build provides shapes, bodies, fixed constraints, commands, stepping, changed state, segment queries, and ground queries, while a no-Jolt build reports typed unavailability | Phase 2 complete |
 | `physicsUsd` | `physicsUsd::physicsUsd` | USD translation, mappings, and synchronization records | 4 |
 | `secondaryMotion` | `secondaryMotion::secondaryMotion` | generic secondary-motion contracts | 6, if admitted |
 | `secondaryMotionVerlet` | `secondaryMotionVerlet::secondaryMotionVerlet` | first CPU solver | 6, if admitted |

diff --git a/docs/design/DESIGN_POLICY.md b/docs/design/DESIGN_POLICY.md
@@ -1,7 +1,7 @@
 # usd-physics-plugins design policy
 
-> **Status: proposed, revised 2026-09-22.** This policy defines intended
-> behavior while Phase 1 extracts the neutral runtime contract. The
+> **Status: proposed, revised 2026-09-23.** This policy defines intended
+> behavior while Phase 3 migrates Stage Runner to the extracted packages. The
 > [capability matrix](../reference/CAPABILITY_MATRIX.md) is the only source for
 > implementation claims.
 >

diff --git a/docs/reference/CAPABILITY_MATRIX.md b/docs/reference/CAPABILITY_MATRIX.md
@@ -4,16 +4,17 @@ This page is the only source of truth for what the current repository tree
 implements. Design documents describe intended behavior; they do not upgrade a
 capability on this page.
 
-> **Tree status (2026-09-23): Phase 2 backend extraction in progress.**
+> **Tree status (2026-09-23): Phase 2 complete; Phase 3 migration in progress.**
 > Buildable and installable `physicsCore` and `physicsJolt` package boundaries
 > exist.
 > `physicsCore` provides neutral rigid-transform values, typed handles, and
 > validated box/body/fixed-constraint descriptors with semantic collision
 > filters, a single-owner world contract, and optional segment and ground
 > query interfaces. `physicsJolt` implements those contracts when a compatible
 > Jolt package is present and retains a typed unavailable fallback otherwise.
-> The Jolt-required OpenStrata intent passes locally; hosted backend evidence
-> and an OpenUSD plugin do not exist yet.
+> The Jolt-required OpenStrata intent passes locally and in hosted Windows and
+> Linux CI. Stage Runner has not migrated to the installed packages, and an
+> OpenUSD plugin does not exist yet.
 
 ## 1. Status vocabulary
 
@@ -62,8 +63,8 @@ capability on this page.
 
 | Capability | Status | Evidence / note |
 | --- | --- | --- |
-| `physicsJolt` package | partial | Installable `physicsJolt::physicsJolt` exposes `backendAvailable()` and `createWorld()`; Jolt-enabled and typed unavailable clean-prefix consumers pass on Windows and Linux, and the Jolt-required OpenStrata intent passes locally; hosted evidence remains open |
-| Jolt initialization and lifetime | partial | Reference-counted factory/type registration, per-world temporary allocator and job system, explicit resource cleanup, and typed errors are covered by Windows/Linux plain-CMake and local Windows OpenStrata evidence; hosted evidence remains open |
+| `physicsJolt` package | supported | Installable `physicsJolt::physicsJolt` exposes `backendAvailable()` and `createWorld()`; Jolt-enabled and typed unavailable clean-prefix consumers pass on Windows and Linux, and the Jolt-required OpenStrata intent passes locally and in the [hosted backend report](../reports/2026-09-23-phase2-hosted-backend.md) |
+| Jolt initialization and lifetime | supported | Reference-counted factory/type registration, per-world temporary allocator and job system, explicit resource cleanup, and typed errors are covered by Windows/Linux plain-CMake, local Windows OpenStrata, and [hosted Windows/Linux](../reports/2026-09-23-phase2-hosted-backend.md) evidence |
 | Jolt body/shape/constraint conversion | supported | Box shapes, static/dynamic bodies, normalized rotations, mass, semantic filters, fixed constraints, force/velocity commands, stepping, state, and cleanup pass focused Windows and Linux tests |
 | Jolt collision and support queries | supported | Closest segment hit, ignored body, support identity, upward normal, distance, validation, and cross-world rejection pass focused Windows and Linux tests |
 | Alternative rigid-body backend | unsupported | No implementation phase committed |

diff --git a/docs/reports/2026-09-23-phase2-hosted-backend.md b/docs/reports/2026-09-23-phase2-hosted-backend.md
@@ -0,0 +1,37 @@
+# 2026-09-23 Phase 2 hosted backend verification
+
+## Scope
+
+This report records the hosted Windows and Linux verification of the extracted
+`physicsJolt` implementation at commit
+`0851d9e3717e11401e1ee1d3ef442a2f29e88781`. GitHub Actions run
+[`35754385903`](https://github.com/animu-sphere/usd-physics-plugins/actions/runs/35754385903)
+was triggered for the `codex/physics-jolt-backend` pull request and completed
+successfully on 2026-09-22 UTC.
+
+The run used the generated OpenStrata source-CI workflow, the `jolt` intent,
+OpenStrata 0.23.2, and Jolt Physics 5.5.0 at commit
+`23dadd0e603f1b321142d4c74df07fce85064989`.
+
+## Result
+
+All three hosted jobs completed successfully:
+
+- `workspace-graph-pr` validated the CI manifest and workspace dependency
+  graph on `ubuntu-24.04`;
+- `workspace-pr-linux` built the pinned Jolt dependency, materialized and
+  validated the pinned runtime, built the workspace, and passed the workspace
+  test suite on `ubuntu-24.04`; and
+- `workspace-pr-windows` performed the equivalent Jolt-required build and test
+  path on `windows-2022`.
+
+Both platform cells passed the `ost build --intent jolt` and
+`ost test --intent jolt` steps. This exercises the focused backend behavior and
+clean-prefix installed-consumer path described by the local Windows and Linux
+Phase 2 reports through the hosted OpenStrata composition.
+
+## Conclusion
+
+The hosted evidence closes the remaining Phase 2 roadmap item. The extracted
+`physicsJolt` package has passing local and hosted Windows/Linux evidence, and
+Stage Runner package migration can begin as Phase 3.
diff --git a/docs/reports/README.md b/docs/reports/README.md
@@ -8,3 +8,4 @@ remain in the [capability matrix](../reference/CAPABILITY_MATRIX.md).
 - [2026-09-22 Phase 0 hosted CI verification](2026-09-22-phase0-hosted-ci.md)
 - [2026-09-22 Phase 2 Windows backend verification](2026-09-22-phase2-windows-backend.md)
 - [2026-09-22 Phase 2 Linux backend verification](2026-09-22-phase2-linux-backend.md)
+- [2026-09-23 Phase 2 hosted backend verification](2026-09-23-phase2-hosted-backend.md)
diff --git a/docs/roadmap/README.md b/docs/roadmap/README.md
@@ -9,8 +9,7 @@ status and ordering.
 
 | Phase | Status | Current outcome |
 | --- | --- | --- |
-| 2 — extract `physicsJolt` | not started | The complete installed Phase 1 contract and selected Jolt 5.5.0 dependency are ready for backend extraction. |
-| 3 — Stage Runner migration | not started | Waits for installable Phase 1–2 packages. |
+| 3 — Stage Runner migration | in progress | Consume the installed Phase 1–2 packages without changing Stage Runner orchestration or compatibility behavior. |
 | 4 — `physicsUsd` foundation | not started | Waits for the neutral rigid-body contract. |
 | 5 — MMD validation | not started | Waits for the USD bridge and a generated vertical-slice fixture. |
 | 6 — secondary-motion core | not started | Deferred until rigid-body extraction is stable and a VRM slice validates the descriptor. |
@@ -22,7 +21,7 @@ version plan exists; release numbers do not belong in the phase definitions.
 
 ## Current plan
 
-[current.md](current.md) contains the ordered Phase 2 extraction work.
+[current.md](current.md) contains the ordered Phase 3 migration work.
 Completed items leave that page and are reflected in the
 [capability matrix](../reference/CAPABILITY_MATRIX.md).
 

diff --git a/docs/roadmap/current.md b/docs/roadmap/current.md
@@ -1,53 +1,67 @@
-# Current roadmap — Phase 2 `physicsJolt` extraction
+# Current roadmap — Phase 3 Stage Runner migration
 
-> **Status: in progress, 2026-09-23.** The Jolt-backed runtime and Windows/Linux
-> plain-CMake/installed-consumer slices are implemented, and the Jolt-required
-> OpenStrata intent passes locally on Windows. Hosted evidence remains before
-> Phase 2 is complete.
+> **Status: in progress, 2026-09-23.** Phase 2 is complete: the installed
+> `physicsCore` and `physicsJolt` packages pass local and hosted Windows/Linux
+> verification. The next slice migrates Stage Runner to those packages while
+> preserving its orchestration and authored compatibility behavior.
 
 ## 1. Outcome
 
-Phase 2 produces an installed `physicsJolt` package that constructs a
-solver-backed world while keeping every Jolt type, identifier, allocator, job
-system, layer, and query implementation private.
+Phase 3 makes `usd-stage-runner` a consumer of the installed packages instead
+of an owner of the neutral physics and Jolt backend implementations.
 
 ```text
-installed physicsCore contract
-        -> physicsJolt world factory
-        -> Jolt resource lifecycle and fixed stepping
-        -> changed state, segment queries, and ground queries
+installed physicsCore + physicsJolt
+        -> Stage Runner composition boundary
+        -> fixed-step orchestration and gameplay capabilities
+        -> incremental runtime-layer synchronization
 ```
 
 ## 2. Available prerequisites
 
-- Phase 1 provides installed neutral values, typed handles, validated
-  descriptors, typed errors, world lifecycle/state, and optional `SegmentQuery`
-  and `GroundQuery` interfaces.
-- Jolt Physics 5.5.0 at commit
-  `23dadd0e603f1b321142d4c74df07fce85064989` is selected in the
-  [dependency contract](../architecture/DEPENDENCIES.md).
-- The Stage Runner extraction baseline records the proven initialization,
-  lifecycle, stepping, changed-state, ignored-body segment, and support-contact
-  behavior to preserve.
-- The package scaffold, exported target, boundary checks, and clean-prefix
-  installed-consumer path already exist.
-
-## 3. Remaining Phase 2 work
-
-- Run the configured Jolt-enabled hosted Windows/Linux Phase 2 cells and
-  record dated evidence.
-- Reconcile any platform-specific Jolt compile options discovered by those
-  cells with the dependency contract before changing the capability claim to
-  fully supported.
-
-## 4. Phase 2 completion criteria
-
-- Falling-body, cleanup, changed-state, segment-query, and ground-query tests
-  pass through the installed `physicsCore` contract.
-- Public `physicsCore` and `physicsJolt` headers expose no Jolt type or native
-  resource identifier.
-- The backend preserves Phase 1 stale, cross-world, validation, error, and
-  changed-state ordering behavior.
-- Package metadata and the `jolt` OpenStrata intent describe the same private
-  Jolt dependency edge.
-- The capability matrix claims only the backend behavior exercised by tests.
+- Phase 1 provides the installed neutral values, handles, descriptors, errors,
+  world contract, and optional segment and ground query capabilities.
+- Phase 2 provides the installed Jolt-backed world factory with passing local
+  and hosted Windows/Linux evidence.
+- The Stage Runner extraction inventory fixes the current public surface,
+  consumers, compatibility importer, fixed-step order, and deterministic parity
+  evidence at its recorded source revision.
+- `StageSession::PhysicsWorldFactory` already gives the standalone and usdview
+  hosts one backend-selection seam.
+
+## 3. Completed locally
+
+- Replaced Stage Runner's repository-local `physicsCore` and `physicsJolt`
+  source edges with installed-package discovery and equivalent OpenStrata
+  requirements.
+- Adapted Stage Runner includes, namespace usage, and math values explicitly at
+  the composition boundary.
+- Moved prim/body mapping, dirty synchronization, and fixed-step delegation from
+  the local `PhysicsRuntime` into `stageRuntime` without moving `PrimId` or
+  `RuntimeWorld` into the external package.
+- Kept the Runner physics schema importer in Stage Runner as a temporary
+  compatibility path that produces neutral external descriptors.
+- Preserved `StageSession::PhysicsWorldFactory` and used the same external Jolt
+  factory in standalone and usdview hosts.
+- Removed the repository-local physics libraries after the installed package
+  path passed all 48 local Windows parity tests.
+
+## 4. Remaining Phase 3 work
+
+- Publish immutable OCI sources for the pinned Windows package artifacts.
+- Produce and publish equivalent Linux package artifacts.
+- Run the Stage Runner hosted Windows and Linux suites from fresh artifact
+  caches and record the evidence.
+
+## 5. Phase 3 completion criteria
+
+- Existing falling-body, character grounding, jump-support, and camera
+  collision scenarios pass against installed `physicsCore` and `physicsJolt`.
+- Stage Runner no longer owns the reusable neutral physics implementation or
+  the Jolt backend, and no Jolt type crosses a public Stage Runner boundary.
+- Prim/body mapping, fixed-step ordering, changed-state synchronization, and
+  discardable runtime-layer behavior remain owned and tested by Stage Runner.
+- Runner physics schema fixtures continue to work through the local
+  compatibility importer; no new `runner:physics:*` property is added.
+- Plain CMake, OpenStrata, standalone, and usdview resolve the same package and
+  world-factory graph.
diff --git a/tests/installed_consumer/CMakeLists.txt b/tests/installed_consumer/CMakeLists.txt
@@ -3,10 +3,20 @@ project(UsdPhysicsInstalledConsumer LANGUAGES CXX)
 
 if(TEST_FAKE_INCOMPATIBLE_JOLT)
   add_library(Jolt::Jolt INTERFACE IMPORTED)
+  set_property(TARGET Jolt::Jolt PROPERTY INTERFACE_COMPILE_DEFINITIONS
+    USD_PHYSICS_TEST_INCOMPATIBLE_JOLT_ABI=1)
 endif()
 
 find_package(physicsCore CONFIG REQUIRED)
 find_package(physicsJolt CONFIG REQUIRED)
+if(NOT DEFINED physicsJolt_BACKEND_AVAILABLE)
+  message(FATAL_ERROR "physicsJolt package must report backend availability")
+endif()
+if(NOT "${physicsJolt_BACKEND_AVAILABLE}" STREQUAL
+       "${EXPECT_PHYSICSJOLT_BACKEND_AVAILABLE}")
+  message(FATAL_ERROR
+    "physicsJolt backend metadata does not match the installed package")
+endif()
 
 add_executable(usd_physics_installed_consumer main.cpp)
 target_compile_features(usd_physics_installed_consumer PRIVATE cxx_std_17)

diff --git a/tests/run_installed_consumer.cmake b/tests/run_installed_consumer.cmake
@@ -5,6 +5,10 @@ endif()
 set(_prefix "${PROJECT_BUILD_DIR}/installed-consumer-prefix")
 set(_build "${PROJECT_BUILD_DIR}/installed-consumer-build")
 set(_mismatch_build "${PROJECT_BUILD_DIR}/incompatible-jolt-consumer-build")
+set(_expected_backend_available OFF)
+if(TEST_JOLT_DIR)
+  set(_expected_backend_available ON)
+endif()
 file(REMOVE_RECURSE "${_prefix}" "${_build}" "${_mismatch_build}")
 
 execute_process(
@@ -38,6 +42,7 @@ set(_configure_args
   -B "${_build}"
   -G "${TEST_GENERATOR}"
   "-DCMAKE_BUILD_TYPE=${TEST_CONFIG}"
+  "-DEXPECT_PHYSICSJOLT_BACKEND_AVAILABLE=${_expected_backend_available}"
   "-DCMAKE_PREFIX_PATH=${_prefix}")
 if(TEST_GENERATOR_PLATFORM)
   list(APPEND _configure_args -A "${TEST_GENERATOR_PLATFORM}")