[Master] Wolverine 6.0

[jeremydmiller]

Status: in-flight (AOT pillar + all 13 extension-package AOT flags + cold-start #1577 Tier 1 + foundation re-pin to the alpha.20 matrix + 6.0.0-alpha.5 cut + Marten 9 test alignment + DCB parity all complete; remaining: cold-start #1577 Tier 2/3 + #2728, feature work JasperFx/CritterWatch#239 / #2221, CI/dev-loop #2810, release-cut tasks tracked in #2745)
Target version: Wolverine 6.0
Milestone: 6.0
Part of [Master] Critter Stack 2026 (JasperFx/jasperfx#217).
Pillars: cold-start (JasperFx/jasperfx#212), AOT compliance (JasperFx/jasperfx#213).
Dedupe pillar (JasperFx/jasperfx#214) is not in scope for Wolverine — that pillar is Marten ↔ Polecat consolidation only.

Wolverine 6 is the messaging/orchestration release of the Critter Stack 2026 wave. The work is dominated by the cold-start and AOT pillars, plus accumulated Wolverine-specific items on the 6.0 milestone (defaults flip to ServiceLocationPolicy.NotAllowed, scheduler integrations, Result-pattern support).

Wolverine's runtime codegen stays — per the Critter Stack 2026 blog post, source-generator conversion is architecturally not feasible for Wolverine. The AOT story leans entirely on JasperFx's existing dotnet run -- codegen write pre-generation path: dev-time codegen produces source files; production publish drops JasperFx.RuntimeCompiler and the trimmer drops Roslyn.

Goals for 6.0

1. Cold-start friendly. Drive down first-message latency from a fresh process. Long-standing issue Optimize Cold Start Times #1577 fits squarely under pillar Code generation goes boom when a route pattern has a dash #212.
2. AOT-clean (Static mode). Wolverine apps that pre-generate handlers via codegen write publish AOT-clean. Runtime codegen remains supported but is annotated with [RequiresDynamicCode] / [RequiresUnreferencedCode].
3. Defaults flip toward best-perf config — most visibly, ServiceLocationPolicy.NotAllowed becomes the Wolverine 6 default (Make ServiceLocationPolicy.NotAllowed the Default in Wolverine 6 #2584).
4. Wolverine-as-MediatR ergonomics — formal Result-pattern support (Formal support for the stupid Result pattern in "Wolverine as MediatR" usage #2221).
5. Scheduler integrations — Quartz.Net + TickerQ (#2507).
6. API cleanup — accumulated [Obsolete] APIs since Wolverine 5 are removed.

Out of scope for Wolverine 6

• Source-generator conversion. Per the blog post: "not remotely possible" — architecturally rejected. Wolverine stays on runtime codegen + AOT annotations.
• Dedupe pillar work ([Pillar] Dedupe Marten ↔ Polecat jasperfx#214). That pillar covers Marten ↔ Polecat only.

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✅ Major milestones already landed

• AOT pillar [AOT pillar] Wolverine.csproj IsAotCompatible=true (tracking) #2746 — CLOSED. Wolverine.csproj builds with 0 IL warnings under EnableTrimAnalyzer + EnableAotAnalyzer on net9.0 + net10.0 (chunks A–U, PRs AOT pillar: foundation + Wolverine.AotSmoke regression-guard #2747 / AOT chunk B: annotate Transports/EnvelopeMapper.cs (#2746) #2753–AOT chunk U: HandlerGraph.cs codegen + bootstrap suppressions (#2746) #2778). Every reflective entry point in runtime-codegen (HandlerGraph.Compile, Forwarders.FindForwards, EnvelopeMapper, all CloseAndBuildAs sites in routing/partitioning/batching/sagas) annotated. IsAotCompatible=true is honest.
• [AOT] Eliminate CloseAndBuildAs<T>(runtimeType) calls — design AOT-compliant replacement #2769 — CLOSED. CloseAndBuildAs<T>(runtimeType) AOT-compliant replacement via pre-populated per-message-type caches (PR AOT #2769 Option A: pre-populate per-message-type CloseAndBuildAs caches #2794, "Option A").
• perf(envelope): pool internal Envelope at Executor.cs InvokeAsync sites (#2726) #2741 — MERGED. Envelope-pool perf optimization at Executor.cs InvokeAsync sites ([perf] Pool Envelope instances for the internal receive pipeline #2726 implementation). Benchmark gate tracked in [Release] Wolverine 6.0 Release Punchlist #2745.
• Make ServiceLocationPolicy.NotAllowed the Default in Wolverine 6 #2584 — CLOSED. ServiceLocationPolicy.NotAllowed is now the Wolverine 6 default.
• [AOT] Research: eliminate FastExpressionCompiler in EnvelopeMapper #2755 — replaced FastExpressionCompiler in EnvelopeMapper with delegate dispatch (PR AOT #2755: replace FastExpressionCompiler in EnvelopeMapper with delegate dispatch #2793).
• [AOT] Eliminate Assembly.ExportedTypes scan for IForwardsTo<T> — make registration explicit (BREAKING) #2757 — replaced IForwardsTo<T> assembly scan with explicit registration (PR AOT #2757: explicit IForwardsTo<T> registration replaces assembly scan (BREAKING) #2795, BREAKING).
• Wolverine.AotSmoke + Wolverine.AotSmoke.Static regression-guard projects in src/Testing/. CI workflow aot.yml runs them on every build via ./build.sh CIAotSmoke.
• Per-extension-package AOT flag flips (first wave) — Wolverine.Postgresql, Wolverine.SqlServer, Wolverine.Sqlite, Wolverine.MySql, Wolverine.Oracle, Wolverine.Newtonsoft, Wolverine.DataAnnotationsValidation, Wolverine.FluentValidation carry IsAotCompatible=true (chunks AE–AL, PRs AOT chunk AE: flip IsAotCompatible=true on Wolverine.Postgresql (#2746) #2789–AOT chunk AL: flip IsAotCompatible=true on Wolverine.FluentValidation (#2746) #2803). Second + third waves (HTTP/integration + serializer/transport) landed 2026-05-19 via PRs Wolverine AOT pass: HTTP + integration extension packages (5 packages) #2851 + Wolverine AOT pass: serializer + transport extension packages (8 packages) #2852 — see below.
• Wolverine.Polecat IMessageOutbox bridge — PR Wolverine.Polecat IMessageOutbox bridge (closes #2774) #2814 (closes Wolverine.Polecat: bridge Polecat IMessageOutbox to Wolverine (mirror of MartenToWolverineMessageBatch) #2774).
• WolverineFx.Http.Newtonsoft extracted — PR #2742: extract WolverineFx.Http.Newtonsoft package #2807 (refs Newtonsoft.Json extraction: Wolverine.Http follow-up #2742).
• Saga.Version reflection ambiguity fixed for new int Version subclass shadows — PR Fix Saga.Version reflection ambiguity for subclasses with 'new int Version' shadow #2828.

2026-05-19 landings (foundation re-align + AOT extension sweep + cold-start Tier 1 + DCB)

• PR Wolverine: re-pin to JasperFx.Events alpha.16 / Marten 9.0-alpha.4 / Polecat 4.0-alpha.8 / Weasel 9.0-alpha.6 (foundation re-align) #2848 — foundation re-pin. Re-pinned onto the Critter Stack 2026 alpha matrix (JasperFx 2.0.0-alpha.20 / JasperFx.Events 2.0.0-alpha.21 / SG alpha.13 / Marten 9.0.0-alpha.4→.5 / Polecat 4.0.0-alpha.8→.10 / Weasel 9.0.0-alpha.7) + wired JasperFx.Events.SourceGenerator for projection dispatch + adapted to Marten 9 / JasperFx 2.0 API renames. Cut 6.0.0-alpha.5.
• PR Wolverine AOT pass: HTTP + integration extension packages (5 packages) #2851 — HTTP + integration AOT cohort (5 packages). Wolverine.HealthChecks, Wolverine.Polecat, Wolverine.Http.Marten, Wolverine.Http.Polecat, Wolverine.Http.FluentValidation now carry IsAotCompatible=true.
• PR Wolverine AOT pass: serializer + transport extension packages (8 packages) #2852 — serializer + transport AOT cohort (8 packages). Wolverine.MemoryPack, Wolverine.MessagePack, Wolverine.Protobuf, Wolverine.Grpc, Wolverine.FluentValidation.Grpc, Wolverine.CosmosDb, Wolverine.ClaimCheck.AmazonS3, Wolverine.ClaimCheck.AzureBlobStorage flagged (wrapper-level annotations where upstream SDKs are reflection-driven). With Wolverine AOT pass: HTTP + integration extension packages (5 packages) #2851 + Wolverine AOT pass: serializer + transport extension packages (8 packages) #2852, every packaged lib except the intentionally-off Wolverine.RuntimeCompilation now carries the AOT flag — AOT pillar Explore the idea of a command to export external annotations for handlers, endpoints, and generated types #213 is closeable.
• PR Wolverine#1577 Tier 1: pre-generated static handler registry (skip handler discovery scan) #2856 — Optimize Cold Start Times #1577 Tier 1. Pre-generated static handler registry; codegen write emits a handler-discovery manifest so Static-mode boot skips the handler-discovery assembly scan.
• PRs fix(tests): partial aggregates + SG analyzer for live FetchForWriting under Marten 9 #2853 / test(marten): align MartenTests with Marten 9 async-only LINQ and Quick append mode #2854 / test(marten): fix AggregateHandler tests under Marten 9 UseIdentityMapForAggregates default #2858 — Marten 9 test alignment. Partial aggregates + SG analyzer for live FetchForWriting; async-only LINQ + Quick append mode; UseIdentityMapForAggregates default opt-out.
• PR DCB: Marten boundary-model test fix + Polecat parity suite + foundation re-pin #2861 — DCB parity. Marten boundary-model test fix + Polecat DCB parity suite + foundation re-pin. Validates the cross-store DCB story (sibling to JasperFx Add routing diagnostics to diagnostics doc page #324 boundary-aggregate evolver + Marten #4510/#4514).
• PR Bound attacker-controlled length fields in EnvelopeSerializer and TCP transport #2844 — security. Bound attacker-controlled length fields in EnvelopeSerializer + TCP transport.

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What's left

Cold-start (JasperFx/jasperfx#212)

• Optimize Cold Start Times #1577 — Optimize cold start times. Wolverine-side master subtask for the cold-start pillar. Tier 1 shipped via PR Wolverine#1577 Tier 1: pre-generated static handler registry (skip handler discovery scan) #2856 (pre-generated static handler registry — Static-mode boot skips handler-discovery scan). Remaining tiers: HTTP-endpoint + FluentValidation-validator registry pre-generation (Tier 1 follow-ons), and the executor-finder + IoC-scan elimination (Tier 2/3). Tier 2 startup-snapshot design tracked separately in Tier 2 cold-start: extend JasperFx codegen with startup snapshot + optional source-generator applicator #2728 (chip staged at .claude/chips/2728-snapshot-extension.md).
• Handler-factory cache — adopt JasperFx.Core.Reflection.GenericFactoryCache (landed in JasperFx 2.0 PR Marten command handler support without requiring Version property #191) on the per-message handler instantiation hot path. (PR AOT #2769 Option A: pre-populate per-message-type CloseAndBuildAs caches #2794 — Option A: pre-populate per-message-type CloseAndBuildAs caches.)
• Audit assembly scanning in handler/saga/middleware discovery. Replace runtime scanning with cached / source-generated discovery where feasible. (PR AOT #2757: explicit IForwardsTo<T> registration replaces assembly scan (BREAKING) #2795 — explicit IForwardsTo<T> registration replaces assembly scan; further per-call-site audit tracked under Optimize Cold Start Times #1577 sub-issues.)
• Cold-start benchmarks land in JasperFx/CritterStackScalability for side-by-side Wolverine 5 vs. Wolverine 6 measurement. Builds on the existing Scalability.WolverinePerfTest project there. (CSS #3 Wolverine cold-start child binary + CSS #4 runtime perf harness shipped via CSS PR Endpoint Configuration Policies #6. The manual harness run is tracked in #2745 — running the harness to capture release-blog numbers is Jeremy's hands.)

AOT (JasperFx/jasperfx#213)

• Set IsAotCompatible=true on Wolverine.csproj once it builds against JasperFx 2.0 + JasperFx.Events 2.0. (src/Wolverine/Wolverine.csproj — flag is set; tracked via [AOT pillar] Wolverine.csproj IsAotCompatible=true (tracking) #2746 — CLOSED.)
• Annotate Wolverine's runtime-codegen surface with [RequiresDynamicCode] / [RequiresUnreferencedCode]. (Chunks A–U complete, PRs AOT pillar: foundation + Wolverine.AotSmoke regression-guard #2747 / AOT chunk B: annotate Transports/EnvelopeMapper.cs (#2746) #2753–AOT chunk U: HandlerGraph.cs codegen + bootstrap suppressions (#2746) #2778. Every reflective entry point annotated per the csproj header note.)
• Audit reflective discovery in handler/saga/transport registration. Annotate or migrate; specifically verify IJasperFxCommand discovery uses the existing JasperFx source generator (Wolverine CLI commands). (Folded into the per-file annotation chunks under [AOT pillar] Wolverine.csproj IsAotCompatible=true (tracking) #2746.)
• Verify codegen write round-trips Wolverine code correctly — pre-generated handlers/middleware load cleanly under TypeLoadMode = Static with no runtime regen path. (PR #2746 sub-PR I: TypeLoadMode.Static codegen-write round-trip smoke (closes the AOT pillar) #2805 — TypeLoadMode.Static codegen-write round-trip smoke, closes the AOT pillar.)
• AOT smoke test — Wolverine in a Static-mode app passes dotnet publish /p:PublishAot=true with no IL2026 / IL3050 warnings beyond the explicitly-annotated runtime-codegen surface. (src/Testing/Wolverine.AotSmoke + src/Testing/Wolverine.AotSmoke.Static; CI workflow .github/workflows/aot.yml runs ./build.sh CIAotSmoke on every build.)

Wolverine-specific 6.0 work (existing milestone issues)

• Make ServiceLocationPolicy.NotAllowed the Default in Wolverine 6 #2584 — Make ServiceLocationPolicy.NotAllowed the default. Breaking default flip; aligns with the "defaults reflect best-observed-perf config" cross-cutting initiative. (CLOSED.)
• #2507 — First-class integration with Quartz.Net and TickerQ. (Tracked in [Release] Wolverine 6.0 Release Punchlist #2745 follow-up triage; Jeremy wants involvement before this lands.)
• Formal support for the stupid Result pattern in "Wolverine as MediatR" usage #2221 — Formal support for the Result pattern in "Wolverine as MediatR" usage. (Tracked in [Release] Wolverine 6.0 Release Punchlist #2745 follow-up triage; Jeremy wants involvement before this lands.)

CI / dev-loop

• Optimize Marten CI build wall-clock by combining test invocations #2810 — Optimize Marten CI build wall-clock by combining test invocations. CIMarten spawns dotnet test once per test class (111 classes in MartenTests); the process-spawn + fixture-init overhead is the gating job on most cross-stack pin-bump PRs (see PR Bump JasperFx pins to alpha.12 / Events alpha.7 + AOT chunk M #2806). Options: batch classes, enable xUnit collection-level parallelism, or split slow daemon tests into a separate project. Same pattern applies to CIPersistence / CIEfCore / other RunSingleProjectOneClassAtATime consumers. (Chip staged at .claude/chips/2810-marten-ci-build-time.md; paused per Jeremy's preference for manual involvement.)

Foundation bump

• Adopt JasperFx 2.0 + JasperFx.Events 2.0 when alphas stabilize. (Directory.Packages.props via PR Wolverine: re-pin to JasperFx.Events alpha.16 / Marten 9.0-alpha.4 / Polecat 4.0-alpha.8 / Weasel 9.0-alpha.6 (foundation re-align) #2848: JasperFx 2.0.0-alpha.20, JasperFx.Events 2.0.0-alpha.21, JasperFx.Events.SourceGenerator 2.0.0-alpha.13 (wired for projection dispatch), JasperFx.RuntimeCompiler 5.0.0-alpha.5, Marten 9.0.0-alpha.5, Polecat 4.0.0-alpha.10, Weasel 9.0.0-alpha.7. Note: Marten + Polecat are one Events alpha behind (alpha.20); the alpha.21 delta is the DCB boundary-aggregate evolver — a convergence re-pin will follow once Marten #4514 lands.)
• TFM alignment: drop net8.0; targets become net9.0;net10.0. Add net11.0 when JasperFx does. (Directory.Build.props sets net9.0;net10.0 as the default for all packaged projects.)
• Version bump to 6.0.0-alpha.1 on all packaged Wolverine projects. (Currently on 6.0.0-alpha.5 per PR Wolverine: re-pin to JasperFx.Events alpha.16 / Marten 9.0-alpha.4 / Polecat 4.0-alpha.8 / Weasel 9.0-alpha.6 (foundation re-align) #2848.)
• Wolverine.RuntimeCompilation project review — its scope and packaging story relative to JasperFx.RuntimeCompiler. (Reviewed: kept as a separate opt-in package WolverineFx.RuntimeCompilation. Description on the csproj explains the contract: production deployments that pre-generate via codegen write don't reference this package; the trimmer drops Roslyn.)

Documentation

• AOT publishing guide specific to Wolverine: pre-generate with codegen write at dev time, publish with Static mode and no AddRuntimeCompilation(), no runtime code generation in production. (docs/guide/aot.md.)
• Migration guide Wolverine 5 → Wolverine 6: TFM bump, ServiceLocationPolicy default change, JasperFx 2.0 adoption, API removals. (docs/guide/migration.md. Pre-release spot-check tracked in [Release] Wolverine 6.0 Release Punchlist #2745.)

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Cross-product dependencies

• JasperFx 2.0 ([Master] JasperFx 2.0 jasperfx#215) and JasperFx.Events 2.0 ([Master] JasperFx.Events 2.0 jasperfx#216) — Wolverine consumes both; AOT and cold-start completion are blocked on their stabilization.
• JasperFx's dotnet run -- codegen write must produce byte-stable output that round-trips cleanly into Wolverine's Static mode. Tracked in the JasperFx 2.0 plan; flagging the dependency here.
• Wolverine does not participate in the dedupe pillar; Marten 9 ↔ Polecat 4 coordination doesn't gate Wolverine 6.

Open design questions

• Cold-start budget: does Wolverine 6 commit to a numeric "first-message latency under N ms in a Lambda-equivalent" or just "trend down, no regressions"? Open question on pillar Code generation goes boom when a route pattern has a dash #212; punted here.

Explicitly out of scope for Wolverine 6

• Source-generator conversion of Wolverine's codegen layer (architectural — out).
• Marten ↔ Polecat dedup work (different pillar, different products).

Linked implementation work

• Cold-start pillar — [Pillar] Cold-start performance jasperfx#212
• AOT pillar — [Pillar] AOT compliance jasperfx#213
• JasperFx 2.0 master plan — [Master] JasperFx 2.0 jasperfx#215
• JasperFx.Events 2.0 master plan — [Master] JasperFx.Events 2.0 jasperfx#216
• Wolverine 6.0 release punchlist (release-cut manual tasks) — [Release] Wolverine 6.0 Release Punchlist #2745