# Script-log Engine Emit + Scripted-Alarm Runtime — Implementation Plan > **For Claude:** REQUIRED SUB-SKILL: use superpowers-extended-cc:subagent-driven-development > (or executing-plans) to implement this plan task-by-task. **Goal:** Make the Script-log page tail real script output, and stand up scripted alarms end-to-end including real OPC UA Part 9 condition nodes + client ack. **Architecture:** Three sequenced layers off one shared seam (a root script logger fanning to file + companion + a new DPS topic sink). Layer 0 = emit (F8 live). Layer 1 = F9 engine runtime on the Akka equipment-namespace runtime. Layer 2 = F14b real Part 9 nodes + events + inbound ack. Design: `docs/plans/2026-06-10-script-log-and-scripted-alarm-runtime-design.md`. Verified gap analysis: `pending.md`. **Tech:** .NET 10, Akka.NET, EF Core (SQL prod / InMemory tests), Serilog, OPC Foundation UA .NET Standard, xUnit + Shouldly, Akka TestKit. No bUnit. **Hard rules (every task):** stage by explicit path — never `git add .`; never stage `sql_login.txt` or `src/Server/ZB.MOM.WW.OtOpcUa.Host/pki/`; never echo the gateway API key into a new tracked file; no force-push, no `--no-verify`. **No Configuration entity / EF migration change** (`ScriptedAlarmState` table already exists). Agent does **not** sign in to the AdminUI — the user drives live `/run`. **Branch:** `feat/scriptlog-alarm-runtime` off `master @ df4c2657` (design committed there). **Reference patterns to mirror:** `VirtualTagHostActor` (host actor shape), `EfAlarmActorStateStore` (EF store shape), the `{{equip}}` two-seam parity work (`Phase7Composer` ↔ `DeploymentArtifact`), `RoslynVirtualTagEvaluator` (evaluator). --- # LAYER 0 — Shared script-log emit + F8 live ### Task 0: Branch + test-project check **Classification:** small · **~2 min** · **Parallelizable with:** none **Files:** none created (branch + verification only) **Steps:** 1. `git switch -c feat/scriptlog-alarm-runtime` (off `master @ df4c2657`). 2. Confirm `tests/Core/ZB.MOM.WW.OtOpcUa.Core.Scripting.Tests/` exists and is in the `.slnx` (it does — `ScriptLoggerFactoryTests.cs` lives there). New Layer-0 tests land here. Confirm `tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/` for Layer-1 tests. 3. `dotnet build ZB.MOM.WW.OtOpcUa.slnx` — green baseline. Commit nothing. --- ### Task 1: `IScriptLogPublisher` + `ScriptLogTopicSink` **Classification:** standard · **~4 min** · **Parallelizable with:** none **Files:** - Create: `src/Core/ZB.MOM.WW.OtOpcUa.Core.Scripting/IScriptLogPublisher.cs` - Create: `src/Core/ZB.MOM.WW.OtOpcUa.Core.Scripting/ScriptLogTopicSink.cs` - Test: `tests/Core/ZB.MOM.WW.OtOpcUa.Core.Scripting.Tests/ScriptLogTopicSinkTests.cs` - Maybe modify: `Core.Scripting.csproj` (add ProjectReference to `Commons` for `ScriptLogEntry` if not already referenced — verify first). **Step 1 — failing tests** (`ScriptLogTopicSinkTests`): - A `LogEvent` (Information) with properties `ScriptId="S1"`, `VirtualTagId="V1"`, `EquipmentId="EQ1"`, message `"hello"` → publisher receives one `ScriptLogEntry` with those fields, `Level=="Information"`, `Message=="hello"`. - `AlarmId` property maps to `ScriptLogEntry.AlarmId`; absent properties → null fields. - A `Debug` event with default `minLevel=Information` → publisher receives **nothing**. - Template message renders (`"v={V}"` + prop V=3 → `"v=3"`). Use a fake `IScriptLogPublisher` capturing entries. **Step 2 — run, expect fail** (types don't exist). **Step 3 — implement:** ```csharp public interface IScriptLogPublisher { void Publish(ScriptLogEntry entry); } public sealed class ScriptLogTopicSink : ILogEventSink { private readonly IScriptLogPublisher _publisher; private readonly LogEventLevel _min; public ScriptLogTopicSink(IScriptLogPublisher publisher, LogEventLevel min = LogEventLevel.Information) { _publisher = publisher; _min = min; } public void Emit(LogEvent e) { if (e is null || e.Level < _min) return; string? P(string k) => e.Properties.TryGetValue(k, out var v) && v is ScalarValue { Value: string s } ? s : null; _publisher.Publish(new ScriptLogEntry( ScriptId: P("ScriptId") ?? P("ScriptName") ?? "unknown", Level: e.Level.ToString(), Message: e.RenderMessage(), TimestampUtc: e.Timestamp.UtcDateTime, VirtualTagId: P("VirtualTagId"), AlarmId: P("AlarmId"), EquipmentId: P("EquipmentId"))); } } ``` (Property-name constants — reuse/extend `ScriptLoggerFactory`'s `ScriptNameProperty`; add `ScriptIdProperty`/`VirtualTagIdProperty`/`AlarmIdProperty`/`EquipmentIdProperty`.) **Step 4 — run tests, expect pass. Step 5 — commit** (`git add` the 3 files by path). --- ### Task 2: Root script logger + `DpsScriptLogPublisher` + Host wiring **Classification:** standard · **~5 min** · **Parallelizable with:** none (depends T1) **Files:** - Create: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Scripting/DpsScriptLogPublisher.cs` (or Host — wherever the `ActorSystem`/`Mediator` is reachable at construction). - Create: `src/Server/ZB.MOM.WW.OtOpcUa.Host/Logging/ScriptRootLoggerFactory.cs` (builds the root `ILogger`: rolling `scripts-*.log` + `ScriptLogCompanionSink` + `ScriptLogTopicSink`). - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Host/Program.cs` (build + register root logger; register `IScriptLogPublisher`). - Test: `tests/.../Core.Scripting.Tests/ScriptRootLoggerFanoutTests.cs` (or Host.Tests). **Steps (TDD):** 1. Failing test: a logger built by `ScriptRootLoggerFactory` with a fake publisher + in-memory companion → an `Error` event reaches the companion mirror AND the topic publisher; a `Debug` event reaches neither topic nor companion (file only). (Assert via fakes; don't assert the physical file.) 2. Implement `DpsScriptLogPublisher` — ctor takes the DPS mediator `IActorRef` (or `ActorSystem`); `Publish` → `mediator.Tell(new Publish("script-logs", entry))` (topic constant `VirtualTagActor.ScriptLogsTopic`). 3. Implement `ScriptRootLoggerFactory.Build(IScriptLogPublisher, config)` → `LoggerConfiguration().WriteTo.File(...).WriteTo.Sink(new ScriptLogCompanionSink(Log.Logger)) .WriteTo.Sink(new ScriptLogTopicSink(publisher, minLevel)).CreateLogger()`. 4. `Program.cs`: resolve the mediator after the ActorSystem is up; register `IScriptLogPublisher` (singleton) + the root `ILogger` (keyed/named for scripts). Min-level from config (`Scripting:LogTopicMinLevel`, default `Information`). 5. Run + commit by path. --- ### Task 3: Rewire evaluators to the root script logger **Classification:** standard · **~5 min** · **Parallelizable with:** none (depends T1, T2) **Files:** - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Host/Engines/RoslynVirtualTagEvaluator.cs` - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Host/Engines/RoslynScriptedAlarmEvaluator.cs` - Modify: `src/Core/ZB.MOM.WW.OtOpcUa.Core.Scripting/ScriptLoggerFactory.cs` (bind the full property set, not just `ScriptName`). - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Host/Program.cs` (inject root logger into the evaluators). - Test: `tests/.../Core.Scripting.Tests/` — evaluator emits via fake publisher. **Steps:** 1. Failing test: a `RoslynVirtualTagEvaluator` built with a root logger wired to a fake publisher; evaluate a script `ctx.Logger.Information("hi"); return 1;` → publisher gets one entry with `ScriptId`/`VirtualTagId` bound and `Message=="hi"`. 2. Replace the static `ScriptLogger` field with a ctor-injected root `ILogger`. Per evaluation, `var log = _root.ForContext("ScriptId", id).ForContext("VirtualTagId", virtualTagId)` (+ `EquipmentId` when available) and pass into the `VirtualTagContext`. Same for the alarm evaluator (binds `AlarmId`). 3. `ScriptLoggerFactory`: add a `Create(scriptId, virtualTagId?, alarmId?, equipmentId?)` overload binding the standard properties (keep the old `Create(scriptName)` for compatibility). 4. `Program.cs`: pass the root logger to both evaluator registrations. 5. Run + commit by path. > Note: `IVirtualTagEvaluator.Evaluate` carries `virtualTagId`; in the live path > `scriptId == virtualTagId`, so Layer 0 binds both from it. Threading a distinct > `EquipmentId` (nice-to-have on the page) is optional here — if it requires an > interface change, defer it to a Layer-1 follow-up rather than expanding T3. --- ### Task 4: Live-verify Layer 0 **Classification:** verification · **Parallelizable with:** none (depends T2, T3) **Steps:** 1. Rebuild docker-dev central nodes (user-driven `/run`). Author a virtual tag whose script calls `ctx.Logger.Information(...)`. 2. Open `/script-log`; drive the dependency so the script evaluates; confirm the line appears live with the right ScriptId/level. Confirm Debug stays off the page, Information+ shows. 3. **Agent does not sign in** — user signs in and drives. Record outcome. No code unless a defect surfaces (→ new fix task). --- # LAYER 1 — F9 engine runtime ### Task 5: `EquipmentScriptedAlarmPlan` + Phase7Composer enrichment **Classification:** standard · **~5 min** · **Parallelizable with:** Task 7, Task 8 **Files:** - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/Phase7Composer.cs` (new record + build the enriched list from `ScriptedAlarm` + `Script` rows). - Test: `tests/Server/ZB.MOM.WW.OtOpcUa.Server.Tests/Phase7/` (or wherever Phase7Composer is tested) — new `Phase7ComposerScriptedAlarmTests.cs`. **Steps:** 1. Failing test: compose two equipments each with a scripted alarm referencing a script; assert each `EquipmentScriptedAlarmPlan` carries the resolved `PredicateSource`, extracted `DependencyRefs` (via `DependencyExtractor`), `AlarmType`, `Severity`, `MessageTemplate`, `HistorizeToAveva`, `Retain`, `Enabled`, `Name`. 2. Add `public sealed record EquipmentScriptedAlarmPlan(string ScriptedAlarmId, string EquipmentId, string Name, string AlarmType, int Severity, string MessageTemplate, string PredicateScriptId, string PredicateSource, IReadOnlyList DependencyRefs, bool HistorizeToAveva, bool Retain, bool Enabled);` 3. In `Compose`: join `ScriptedAlarm.PredicateScriptId → Script.SourceCode`; run `DependencyExtractor.Extract(source).Reads` (∪ `MessageTemplate` token paths) for `DependencyRefs`; project into the new list on the composition result. Skip `Enabled=false` alarms (or carry the flag — carry it; host decides). Drop alarms whose script is missing with a structured warning (don't throw the whole compose). 4. Run + commit by path. --- ### Task 6: DeploymentArtifact parity for the alarm plan **Classification:** standard · **~5 min** · **Parallelizable with:** Task 7, Task 8 (depends T5) **Files:** - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DeploymentArtifact.cs` (encode/decode `EquipmentScriptedAlarmPlan`; add `Phase7CompositionResult.EquipmentScriptedAlarms`; filter-by-equipment like `EquipmentVirtualTags` at :263). - Test: `tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/` — artifact round-trip + parity with the Composer for the same input. **Steps:** 1. Failing test: build a composition via `Phase7Composer`, serialize to artifact, parse back → `EquipmentScriptedAlarms` is byte-identical (same discipline as the `{{equip}}` parity tests). Equipment-filter test (only alarms for resident equipment survive). 2. Add the field to `Phase7CompositionResult`; mirror the `EquipmentVirtualTags` encode/decode/filter exactly (`:202`, `:263`). 3. Run + commit by path. --- ### Task 7: `DependencyMuxTagUpstreamSource` **Classification:** standard · **~4 min** · **Parallelizable with:** Task 5, Task 6, Task 8 **Files:** - Create: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/ScriptedAlarms/DependencyMuxTagUpstreamSource.cs` (implements `Core.ScriptedAlarms`/`Core.VirtualTags` `ITagUpstreamSource`). - Test: `tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/ScriptedAlarms/DependencyMuxTagUpstreamSourceTests.cs` **Steps:** 1. Failing tests: `Push(path, snapshot)` updates cache so `ReadTag(path)` returns it; `SubscribeTag(path, obs)` → `obs` fires on the next `Push`; `ReadTag` for an unknown path returns a Bad-quality snapshot; dispose removes the observer. 2. Implement: a thread-safe cache (`ConcurrentDictionary`) + per-path observer list; `Push` updates cache then invokes observers; `ReadTag` reads cache (Bad if absent); `SubscribeTag` returns an `IDisposable` that deregisters. The host actor calls `Push` from its `DependencyValueChanged` handler. Value wrap: `new DataValueSnapshot(value, StatusCode:0, ts, ts)`. 3. Run + commit by path. --- ### Task 8: `EfAlarmConditionStateStore : IAlarmStateStore` **Classification:** standard · **~5 min** · **Parallelizable with:** Task 5, Task 6, Task 7 **Files:** - Create: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/ScriptedAlarms/EfAlarmConditionStateStore.cs` - Test: `tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/ScriptedAlarms/EfAlarmConditionStateStoreTests.cs` (in-memory EF). **Steps:** 1. Failing tests (in-memory `OtOpcUaConfigDbContext`): `SaveAsync(state)` then `LoadAsync(alarmId)` round-trips Enabled/Acked/Confirmed/Shelving(+UnshelveAtUtc)/ LastAck*/LastConfirm*/Comments; `LoadAsync` of an unknown id → null; `ActiveState` is **not** persisted (a saved state's Active is ignored on load — load returns the stored operator state, Active defaults). Comments JSON round-trips. 2. Implement mapping `AlarmConditionState` ↔ `ScriptedAlarmState` entity (mirror `EfAlarmActorStateStore`'s `IDbContextFactory` upsert pattern; serialize `ImmutableList` ↔ `CommentsJson`). Map enum states ↔ the entity's string columns. 3. Run + commit by path. --- ### Task 9: `ScriptedAlarmHostActor` **Classification:** high-risk · **~5 min** · **Parallelizable with:** none (depends T6, T7, T8; needs Layer 0 T2/T3 root logger) **Files:** - Create: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/ScriptedAlarms/ScriptedAlarmHostActor.cs` - Test: `tests/Server/ZB.MOM.WW.OtOpcUa.Runtime.Tests/ScriptedAlarms/ScriptedAlarmHostActorTests.cs` (Akka TestKit + a real engine with the fake upstream, or a fake engine seam). **Design:** mirrors `VirtualTagHostActor`. Owns one `ScriptedAlarmEngine` (built with the `DependencyMuxTagUpstreamSource`, the `EfAlarmConditionStateStore`, a `ScriptLoggerFactory` wrapping the **Layer 0 root logger**, and the engine's root logger). Message `ApplyScriptedAlarms(IReadOnlyList Plans)`. **Steps:** 1. Failing TestKit tests: - `ApplyScriptedAlarms` with one alarm → engine loaded (assert via a probe/seam); registers interest with the (probe) mux for the alarm's dep refs. - A `DependencyValueChanged` that makes the predicate true → the host tells the (probe) `OpcUaPublishActor` a `WriteAlarmState(alarmId, active:true, …)`, tells the (probe) historian an `AlarmHistorianEvent` (when `HistorizeToAveva`), and publishes an `AlarmTransitionEvent` on `alerts`. - Re-`ApplyScriptedAlarms` with a different set reloads the engine (LoadAsync replace). 2. Implement: on `ApplyScriptedAlarms`, build `ScriptedAlarmDefinition`s from the plans (map `AlarmType`→`AlarmKind`, `Severity`→`AlarmSeverity`, `EquipmentId`→`EquipmentPath`), `engine.LoadAsync`; register mux interest for `⋃ DependencyRefs`; on `DependencyValueChanged` → `_upstream.Push(...)`. Subscribe `engine.OnEvent` once → map `ScriptedAlarmEvent.Condition` to `(active, acknowledged)` → `OpcUaPublishActor.WriteAlarmState`; map → `AlarmHistorianEvent` → historian (if Historize); publish `AlarmTransitionEvent` on `alerts`. Dispose engine in `PostStop`. 3. Run targeted tests (`dotnet test --filter ScriptedAlarmHostActor`). Commit by path. --- ### Task 10: Spawn + apply in DriverHostActor **Classification:** standard · **~4 min** · **Parallelizable with:** none (depends T9) **Files:** - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DriverHostActor.cs` (spawn `ScriptedAlarmHostActor` next to `VirtualTagHostActor` ~:197; tell `ApplyScriptedAlarms(composition.EquipmentScriptedAlarms)` next to the vtag apply ~:532; add an override field for tests like `_virtualTagHostOverride`). - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/ServiceCollectionExtensions.cs` if the host needs new injected deps (EF store factory, root logger, historian ref). - Test: extend `DriverHostActorTests` — apply pushes `ApplyScriptedAlarms`. **Steps:** mirror the VirtualTag spawn/apply exactly; thread `_opcUaPublishActor`, `_dependencyMux`, the EF store, the root logger, the historian actor ref. Run + commit. --- ### Task 11: Retire the orphaned actor + F9b evaluator **Classification:** small · **~3 min** · **Parallelizable with:** none (depends T9, T10) **Files:** - Delete: `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/ScriptedAlarms/ScriptedAlarmActor.cs` (+ its tests) and `src/Server/ZB.MOM.WW.OtOpcUa.Host/Engines/RoslynScriptedAlarmEvaluator.cs`. - Modify: `src/Server/ZB.MOM.WW.OtOpcUa.Host/Program.cs` (remove F9b DI registration, lines ~110-114) and any `IScriptedAlarmEvaluator` references. Keep `EfAlarmActorStateStore` only if nothing else uses it — otherwise delete with the actor. **Steps:** delete, fix build, run full `dotnet test` for the touched projects, commit by path. (If something unexpectedly depends on these, stop and surface — don't expand scope.) --- ### Task 12: Live-verify Layer 1 **Classification:** verification · **Parallelizable with:** none (depends T10, T11) **Steps:** rebuild docker-dev; author a scripted alarm whose predicate references a live tag; drive the tag; confirm the alarm node flips active/clear, the historian queue advances (`/alarms/historian`), the `alerts`/Alerts page shows it, and predicate `ctx.Logger` output appears on `/script-log`. User drives sign-in. Defects → new tasks. --- # LAYER 2 — F14b real Part 9 + client ack ### Task 13: SDK research spike (DeepWiki) **Classification:** small (research) · **~5 min** · **Parallelizable with:** Layer-1 tasks **Steps:** Use the DeepWiki MCP (`OPCFoundation/UA-.NETStandard`) to confirm: how to create + add an `AlarmConditionState` (and Limit/OffNormal/Discrete subtypes) under a parent in a `CustomNodeManager2`; how to set ActiveState/AckedState/ConfirmedState/ ShelvingState/Severity/Retain; how transitions fire events (`ReportEvent`); how inbound `Acknowledge`/`Shelve`/`Confirm` method calls are dispatched + where to hook them. Write findings to `docs/v2/f14b-part9-sdk-notes.md` (committed). This de-risks T14-T17. --- ### Task 14: Real condition-node materialisation **Classification:** high-risk · **~5 min** · **Parallelizable with:** none (depends T13) **Files:** `src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/OtOpcUaNodeManager.cs` (replace the placeholder `[active, ack]` variable in `WriteAlarmState` / add a `MaterialiseAlarmCondition` path per `AlarmType`); `Phase7Applier.cs` (call the new materialiser); tests where the SDK allows (node existence/type assertions). **Steps:** create real condition nodes on materialise; keep `WriteAlarmState` as a thin shim during transition or replace its callers. Run + commit. (SDK threading: all via the pinned `OpcUaPublishActor` dispatcher.) --- ### Task 15: Richer alarm-state bridge **Classification:** standard · **~4 min** · **Parallelizable with:** Task 17 (depends T14, T9) **Files:** `src/Server/ZB.MOM.WW.OtOpcUa.Runtime/OpcUa/OpcUaPublishActor.cs` (new message carrying the full `AlarmConditionState`, not 2 bools); `ScriptedAlarmHostActor` bridge (send the richer message); `OtOpcUaNodeManager` (apply full state to the condition). Tests: message mapping. --- ### Task 16: Event firing on transition **Classification:** high-risk · **~5 min** · **Parallelizable with:** none (depends T14, T15) **Files:** `OtOpcUaNodeManager.cs` (`condition.ReportEvent(...)` on state change). Tests: mapping/coverage where feasible; behaviour proven in T19. --- ### Task 17: Inbound method dispatch + ack plumbing **Classification:** high-risk · **~5 min** · **Parallelizable with:** Task 15 (depends T14) **Files:** `OtOpcUaNodeManager.cs` (wire Acknowledge/Confirm/AddComment/OneShotShelve/ TimedShelve/Unshelve handlers → route to a control-plane message → `ScriptedAlarmHostActor` → `engine.Async(conditionId, principal, comment, ct)`); the security gate at the `AlarmAck` tier (reuse the LDAP-group→OPC-UA-permission map). Tests: method→engine routing with a fake engine; permission gate allows/denies by tier. --- ### Task 18: AdminUI ack/shelve control **Classification:** standard · **~4 min** · **Parallelizable with:** none (depends T17) **Files:** `src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Components/Pages/ScriptedAlarms.razor` (+ a control-plane command service) — ack/shelve buttons route to the same engine ops as T17. Tests: the control-plane command service (no bUnit; live-verify the razor in T19). --- ### Task 19: Live-verify Layer 2 (Client.CLI) **Classification:** verification · **Parallelizable with:** none (depends T16, T17, T18) **Steps:** with docker-dev up, use `Client.CLI` `alarms` + `subscribe` to confirm a real condition appears, fires events on transition, and a client `Acknowledge` round-trips (state flips, event fires, persists). Confirm AdminUI ack does the same. User drives. --- ### Task 20: Docs + finish **Classification:** small · **~5 min** · **Parallelizable with:** none (depends all) **Files:** update `docs/ScriptedAlarms.md`, `docs/VirtualTags.md`, `docs/v2/Runtime.md` (F8/F9 now wired), **correct the stale `docs/v2/phase-7-status.md` alarm-runtime status**, add a CLAUDE.md note for the script-log emit + scripted-alarm runtime. Delete/condense `pending.md` (its content now lives in the design + these docs). Then run superpowers-extended-cc:finishing-a-development-branch (full `dotnet test`, merge to master). --- ## Execution notes - **Parallel dispatch:** Layer 0 is serial (T1→T2→T3→T4). Layer 1: **T5→T6** serial (composer→artifact parity); **T7, T8 parallel** with T5/T6 (disjoint files); T9 waits on T6/T7/T8; T10→T11→T12 serial. Layer 2: T13 first; **T15 ∥ T17** after T14; T16 after T15; T18 after T17; T19/T20 last. - **One writer at a time** within a shared file (Program.cs touched by T2/T3/T11; OtOpcUaNodeManager by T14/T15/T16/T17 — serialize those). - **Layer boundaries are natural checkpoints** — Layer 0 is independently shippable; pause for review after T4 and after T12 before committing to the Layer 2 SDK epic.