feat(simulate): flow model B5 Content Factory v2 (stacked on #5559)

README.md

@@ -114,7 +114,7 @@ publishing — all backed by YAML provable contracts that fail CI on drift.
 | Metric | Count | Source of truth |
 |-------:|------:|---|
 | Workspace crates | **81** workspace crates | `cargo metadata --no-deps` (NOT `ls crates/` — 4 are `exclude`d, 1 has no Cargo.toml) |
-| Provable contracts | **<!-- CONTRACT_COUNT_START -->1984<!-- CONTRACT_COUNT_END -->** provable contracts | `contracts/census.json` `.n_files` — the set `pv lint` walks (`pv census`, ONT-001 ONT-1; regenerated by `make contracts`, written by `make readme-sync`, guarded by `scripts/check_readme_claims.sh`) |
+| Provable contracts | **<!-- CONTRACT_COUNT_START -->1985<!-- CONTRACT_COUNT_END -->** provable contracts | `contracts/census.json` `.n_files` — the set `pv lint` walks (`pv census`, ONT-001 ONT-1; regenerated by `make contracts`, written by `make readme-sync`, guarded by `scripts/check_readme_claims.sh`) |
 | CLI commands | **113** CLI commands | `contracts/apr-cli-commands-v1.yaml` §`commands` (parse the list; `apr --help` also lists `help` itself, and `grep -c '^  - name:'` gives 119 — other same-indent `name:` keys exist in the file) |
 | Book CLI chapters | **114** chapters | `ls book/src/cli/*.md` |
 | Book lib chapters | **73** chapters | `ls book/src/lib/*.md` (parity with `pub mod`) |
@@ -403,7 +403,7 @@ falsification_tests:
   prediction: apr validate bad-model.apr exits non-zero
 ```
 
-The tree carries <!-- CONTRACT_COUNT_START -->1984<!-- CONTRACT_COUNT_END --> contracts across inference, training, quantization, attention, FFN,
+The tree carries <!-- CONTRACT_COUNT_START -->1985<!-- CONTRACT_COUNT_END --> contracts across inference, training, quantization, attention, FFN,
 tokenization, model formats, CLI safety — and this README itself.
 
 ## Migration from old crates

contracts/contracts.nt

@@ -9716,6 +9716,13 @@
 <https://ont.paiml.dev/v1alpha1/contract/course-flow-batch-wip-v1> <https://ont.paiml.dev/v1alpha1/id> "course-flow-batch-wip-v1"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/contract/course-flow-batch-wip-v1> <https://ont.paiml.dev/v1alpha1/name> "course-flow-batch-wip"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/contract/course-flow-batch-wip-v1> <https://ont.paiml.dev/v1alpha1/version> "1.0.0"^^<http://www.w3.org/2001/XMLSchema#string> .
+<https://ont.paiml.dev/v1alpha1/contract/course-flow-content-factory-v2-v1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/ns/prov#Entity> .
+<https://ont.paiml.dev/v1alpha1/contract/course-flow-content-factory-v2-v1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <https://ont.paiml.dev/v1alpha1/Contract> .
+<https://ont.paiml.dev/v1alpha1/contract/course-flow-content-factory-v2-v1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <https://ont.paiml.dev/v1alpha1/Kernel> .
+<https://ont.paiml.dev/v1alpha1/contract/course-flow-content-factory-v2-v1> <https://ont.paiml.dev/v1alpha1/file> "contracts/course-flow-content-factory-v2-v1.yaml"^^<http://www.w3.org/2001/XMLSchema#string> .
+<https://ont.paiml.dev/v1alpha1/contract/course-flow-content-factory-v2-v1> <https://ont.paiml.dev/v1alpha1/id> "course-flow-content-factory-v2-v1"^^<http://www.w3.org/2001/XMLSchema#string> .
+<https://ont.paiml.dev/v1alpha1/contract/course-flow-content-factory-v2-v1> <https://ont.paiml.dev/v1alpha1/name> "course-flow-content-factory-v2"^^<http://www.w3.org/2001/XMLSchema#string> .
+<https://ont.paiml.dev/v1alpha1/contract/course-flow-content-factory-v2-v1> <https://ont.paiml.dev/v1alpha1/version> "1.0.0"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/contract/cpp-type-preservation-v1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/ns/prov#Entity> .
 <https://ont.paiml.dev/v1alpha1/contract/cpp-type-preservation-v1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <https://ont.paiml.dev/v1alpha1/Contract> .
 <https://ont.paiml.dev/v1alpha1/contract/cpp-type-preservation-v1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <https://ont.paiml.dev/v1alpha1/Kernel> .
@@ -23389,6 +23396,7 @@
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/apr-cli/"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/apr-cli/Cargo.toml"^^<http://www.w3.org/2001/XMLSchema#string> .
+<https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/aprender-compute"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/aprender-compute/"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/aprender-contracts-cli/"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/aprender-contracts-macros/"^^<http://www.w3.org/2001/XMLSchema#string> .
@@ -23413,7 +23421,6 @@
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "crates/aprender-train/"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "docs/BEATS.md"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "docs/specifications/aprender-monorepo-consolidation.md"^^<http://www.w3.org/2001/XMLSchema#string> .
-<https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "docs/ssc-training-status-2026-03-22.md"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "scripts/apr_bin.sh"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "scripts/bump-version.sh"^^<http://www.w3.org/2001/XMLSchema#string> .
 <https://ont.paiml.dev/v1alpha1/llm/claude-md> <https://ont.paiml.dev/v1alpha1/llm/referencedPath> "scripts/check_clippy_current_stable.sh"^^<http://www.w3.org/2001/XMLSchema#string> .

contracts/course-flow-content-factory-v2-v1.yaml

@@ -0,0 +1,85 @@
+metadata:
+  version: "1.0.0"
+  created: "2026-10-18"
+  author: PAIML Engineering
+  registry: true
+  references:
+    - "Little, J.D.C. (1961), A Proof for the Queuing Formula L = lambda W."
+    - "Denning, P.J. and Buzen, J.P. (1978), The Operational Analysis of Queueing Network Models (utilization and forced flow laws)."
+    - "flow model spec, internal (eqs 1, 2, 3, 5, 6, 14)"
+  description: "course_flow Content Factory v2: fan-out to three renditions, rework loop, GPU priority, build work vs elapsed"
+
+name: course-flow-content-factory-v2
+version: "1.0.0"
+scope: "crates/aprender-simulate/src/scenarios/course_flow.rs"
+
+description: |
+  Content Factory v2 is opt-in on CourseFlowConfig; the defaults reproduce the
+  original course_flow model. With fan_out, every master fans out to R = 3
+  renditions with no split, so every course takes the staging lanes and the
+  stage busy fraction meets the utilization law. A rework loop sends a share
+  alpha of masters back to build, so build carries B / (1 - alpha) passes a day.
+  The GPU serves the trunk first while the recent course W exceeds a threshold,
+  else Shorts, and carries LinkedIn feed renders beside the Shorts. Build work
+  time (holds a builder; sizing) is split from build elapsed time (lead time).
+
+equations:
+  fan_out_forced_flow:
+    description: "launches per day = B * R with R = 3 (flow model eq 3)"
+    formula: "launches_per_day = 3 * courses_per_day"
+
+  stage_utilization:
+    description: "stage busy = B * t_sc / (1440 * lanes) = 5 * 360 / (1440 * 2) = 0.625 (flow model eq 6)"
+    formula: "|stage_util - B * t_sc / (1440 * lanes)| <= 0.02"
+
+  rework_build_utilization:
+    description: "build busy = B * t_b / (1440 * N_b) / (1 - alpha); at alpha = 0.16 that is 0.795 / 0.84 <= 0.95 (flow model eqs 2, 14)"
+    formula: "util_build <= 0.95 and |util_build - 0.795 / (1 - alpha)| <= 0.02"
+
+  gpu_utilization:
+    description: "GPU busy = (B * t_g + (B * k + 4) * t_v) / 1440 (flow model eq 5)"
+    formula: "|util_render - (B * t_g + (B * k + 4) * t_v) / 1440| <= 0.02"
+
+  gpu_priority_rule:
+    description: "trunk first while the recent course W > threshold, else Shorts; the rule reorders and cannot add GPU minutes"
+    formula: "pick(render) = course iff W_recent > w_threshold"
+
+  build_work_vs_elapsed:
+    description: "a builder holds t_b_work (sizing); lead time carries t_b_elapsed (flow model eqs 1, 2)"
+    formula: "util_build = B * t_b_work / (1440 * N_b) and dW = t_b_elapsed - t_b_work"
+
+falsification:
+  - id: FALSIFY-COURSE_FLOW_CF_V2_001
+    description: "the stage busy fraction matches the eq 6 law 62.5% within 2 points under fan-out"
+    test: "coursera_stage_matches_the_law_within_two_points in crates/aprender-simulate/src/scenarios/course_flow.rs"
+    evidence: "cargo test -p aprender-simulate --lib course_flow"
+
+  - id: FALSIFY-COURSE_FLOW_CF_V2_002
+    description: "at alpha = 0.16 build busy is at most 95% and within 2 points of 0.795 / (1 - alpha)"
+    test: "rework_at_alpha_016_keeps_build_at_or_under_95_percent in crates/aprender-simulate/src/scenarios/course_flow.rs"
+    evidence: "cargo test -p aprender-simulate --lib course_flow"
+
+  - id: FALSIFY-COURSE_FLOW_CF_V2_003
+    description: "fan-out launches three renditions per master; the legacy split launches one"
+    test: "fan_out_launches_three_renditions_per_master in crates/aprender-simulate/src/scenarios/course_flow.rs"
+    evidence: "cargo test -p aprender-simulate --lib course_flow"
+
+  - id: FALSIFY-COURSE_FLOW_CF_V2_004
+    description: "the GPU serves the trunk first only while W is over the threshold, and only on the GPU"
+    test: "gpu_serves_trunk_first_only_while_w_is_over_the_threshold in crates/aprender-simulate/src/scenarios/course_flow.rs"
+    evidence: "cargo test -p aprender-simulate --lib course_flow"
+
+  - id: FALSIFY-COURSE_FLOW_CF_V2_005
+    description: "GPU busy matches the eq 5 law with Shorts and four LinkedIn feed renders a day"
+    test: "gpu_carries_trunk_shorts_and_four_linkedin_renders in crates/aprender-simulate/src/scenarios/course_flow.rs"
+    evidence: "cargo test -p aprender-simulate --lib course_flow"
+
+  - id: FALSIFY-COURSE_FLOW_CF_V2_006
+    description: "build work sizes the station; build elapsed beyond work moves lead time, not build busy"
+    test: "build_work_sizes_the_station_and_elapsed_drives_lead_time in crates/aprender-simulate/src/scenarios/course_flow.rs"
+    evidence: "cargo test -p aprender-simulate --lib course_flow"
+
+  - id: FALSIFY-COURSE_FLOW_CF_V2_007
+    description: "the v2 inputs round-trip through the ledger inputs and the sim block"
+    test: "v2_inputs_round_trip_through_the_ledger_and_sim_block in crates/aprender-simulate/src/scenarios/course_flow.rs"
+    evidence: "cargo test -p aprender-simulate --lib course_flow"

contracts/witness/811c78184eb2609244c59534f015f0be2f90923120a3027c176ad56723d0d850.json

@@ -1,7 +1,7 @@
 {
-  "census_id_set_sha256": "7597b4ad189f534dd58cda55c9b1fe29e6339ddb77fd5f40969b4a028eed8f88",
+  "census_id_set_sha256": "1ff4f1bffcb59d87af86465a6fb83b5959988801194fa4436da56a73b2c62b8e",
   "relations_sha256": "811c78184eb2609244c59534f015f0be2f90923120a3027c176ad56723d0d850",
-  "reasoner_git_sha": "461bf9ef1921a8fbea4bc338f21b566ec342a95e",
+  "reasoner_git_sha": "4c0a87672d499188eb59bc4ea6969dfdc8beff45",
   "checkable_n": 87,
   "result": {
     "kind": "model",