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3rd November 2026CritterWatch 1.2: See Inside Your Event Store, Documents, Sagas and SchedulesCritterWatch 1.2 turns the console into a real explorer for what your Critter Stack services hold: an overview of every event store, a Step Through tab for projections, a Document Store Explorer that checks your documents still deserialize, saga instances with their state and pending timeouts, a Schedule Explorer that tells you what a schedule is actually doing, and an Event Model you can drill into.
19th October 2026Rebuilding Projections Without DowntimeWolverine 6.51 adds a warm-up node role for blue/green deployments: spin up the new release's nodes with no messaging at all, let them rebuild the new versions of your Marten or Polecat projections off to the side, and only cut over once they've caught up. Here's how that fits together with Marten's versioned projections, Wolverine's capability-based agent assignment, and the new side-effect gate, and why a client with a very large system and a habit of revising projections needed all of it.
15th October 2026Wolverine's Agent Assignment at ScaleHow Wolverine's leadership election and agent assignment subsystem grew up: why it exists, what 512 databases and 18,000 agents taught us about reassignment swarms and hysteresis, how we test it now, and a preview of dedicated warm-up nodes for blue/green projection deployments.
30th September 2026Event Sourcing on SQL Server with PolecatIf your shop runs on SQL Server and you've been eyeing Event Sourcing, Polecat is the most full featured event store you can get for SQL Server in .NET. It's built on the same shared infrastructure and a decade of production lessons from Marten, it has a first class Wolverine integration for CQRS, CritterWatch can monitor it, and JasperFx Software supports it. Here's the tour.
21st September 2026Every Lever Marten Gives You for Scaling a Big Event Sourcing SystemA tour of everything in Marten and Wolverine for scaling large event sourced systems: Quick Append, hot/cold event archiving, stream compacting, binary event serialization, read replicas, per-tenant partitioning, database per tenant and sharding, ancillary stores per module, projection lifecycles, strongly consistent async projections, partitioned projection data, and Wolverine-managed projection distribution.9th September 2026Event Sourcing Quick Start with MartenLet's get up and running with event sourcing using Marten
18th August 2026Meet Fisher, and One Handler Across Three Databases: The Critter Stack Since August 2ndSixty-three releases in sixteen days across Marten, Wolverine, Polecat, Fisher, Weasel, and the shared JasperFx libraries. Fisher brings event sourcing and document storage to SQLite with no server at all, the shared contracts wave means the same Wolverine handler now runs on PostgreSQL, SQL Server, or SQLite without naming a store, and a projection loader bug that silently skipped events makes this an upgrade you should not sit on.
14th August 2026What a Critter Stack Workshop Actually Looks LikeWe've run Critter Stack workshops for several teams now, and no two have been the same. One went deep on asynchronous messaging, another on Wolverine's HTTP endpoint and message handler hybrids, a third on using Marten projections to build denormalized views for reporting screens. The material is built and ready — what it turns into depends on what your team actually needs.11th August 2026Event Sourcing Without the Eventual Consistency Tax: Strong Consistency Options in Marten and PolecatMost event sourcing stacks make eventual consistency mandatory: events in one database, read models in another, and a subscription in between. Marten and Polecat keep events and read models in one database, which unlocks a dial no one else offers — projections snapshotted in the same transaction as the events, FetchLatest reads that are accurate even with async projections, wait-for-non-stale queries, and test automation that makes asynchronous projections actually testable.5th August 2026Metadata All the Way Down: Correlation, Causation, and Headers Across Wolverine, Marten, and PolecatEvery serious event sourced system eventually needs to answer 'what caused this event, and who did it?' The Critter Stack establishes correlation, causation, saga, user, and tenant metadata on Wolverine message envelopes — seeded straight from OpenTelemetry activities — then relays all of it onto the events Marten and Polecat store, with storage you can dial from lean to rich.
27th July 2026Announcing CritterWatch 1.0 RC 1The first release candidate for CritterWatch 1.0 — a purpose-built monitoring and operations console for the Critter Stack that shows you the system you actually shipped, watches it for you, hands your AI assistant a real control surface, and gives you a proper cockpit for the event store.21st July 2026Never Skip an Event: Hardening Marten's High Water DetectionA deep look at the recent hardening of Marten's async projection high water detection -- why an in-flight transaction gap is dangerous, and how transaction evidence keeps projections from ever silently skipping an event.11th June 2026Polecat: A SQL Server-Native Event Store and Document DatabasePolecat is an event store and lightweight document database for .NET, backed by SQL Server 2025. It brings the proven Marten development model — same IDocumentStore API, projections, and async daemon — to SQL Server shops without a database migration.22nd March 2026Announcing Polecat: Event Sourcing with SQL ServerPolecat is a new JasperFx library that brings Marten's proven Event Sourcing and document database model to SQL Server 2025 — the best technical option for Event Sourcing with SQL Server in .NET.13th December 2023Practical Introduction to Event SourcingOskar Dudycz's webinar for anyone interested in Event Sourcing but unsure where to start.
15th November 2023The Critter Stack at .NET 2023Jeremy's .NET 2023 talk on CQRS with Event Sourcing using Marten and Wolverine: lower code ceremony, a great local developer story, testable domain logic, and built-in diagnostics.30th July 2023CQRS is Easier than You Think!Oskar Dudycz's talk on why CQRS does not have to be scary, and how the Critter Stack keeps it approachable on .NET.27th July 2023Marten as Event StoreMarten pairs its document database with a full event store on PostgreSQL. A short orientation, with pointers to the CoDe Magazine article and Oskar's NDC Oslo 2023 talk.
Event Sourcing
Posts tagged Event Sourcing
3rd November 2026CritterWatch 1.2: See Inside Your Event Store, Documents, Sagas and SchedulesCritterWatch 1.2 turns the console into a real explorer for what your Critter Stack services hold: an overview of every event store, a Step Through tab for projections, a Document Store Explorer that checks your documents still deserialize, saga instances with their state and pending timeouts, a Schedule Explorer that tells you what a schedule is actually doing, and an Event Model you can drill into.19th October 2026Rebuilding Projections Without DowntimeWolverine 6.51 adds a warm-up node role for blue/green deployments: spin up the new release's nodes with no messaging at all, let them rebuild the new versions of your Marten or Polecat projections off to the side, and only cut over once they've caught up. Here's how that fits together with Marten's versioned projections, Wolverine's capability-based agent assignment, and the new side-effect gate, and why a client with a very large system and a habit of revising projections needed all of it.15th October 2026Wolverine's Agent Assignment at ScaleHow Wolverine's leadership election and agent assignment subsystem grew up: why it exists, what 512 databases and 18,000 agents taught us about reassignment swarms and hysteresis, how we test it now, and a preview of dedicated warm-up nodes for blue/green projection deployments.30th September 2026Event Sourcing on SQL Server with PolecatIf your shop runs on SQL Server and you've been eyeing Event Sourcing, Polecat is the most full featured event store you can get for SQL Server in .NET. It's built on the same shared infrastructure and a decade of production lessons from Marten, it has a first class Wolverine integration for CQRS, CritterWatch can monitor it, and JasperFx Software supports it. Here's the tour.21st September 2026Every Lever Marten Gives You for Scaling a Big Event Sourcing SystemA tour of everything in Marten and Wolverine for scaling large event sourced systems: Quick Append, hot/cold event archiving, stream compacting, binary event serialization, read replicas, per-tenant partitioning, database per tenant and sharding, ancillary stores per module, projection lifecycles, strongly consistent async projections, partitioned projection data, and Wolverine-managed projection distribution.9th September 2026Event Sourcing Quick Start with MartenLet's get up and running with event sourcing using Marten18th August 2026Meet Fisher, and One Handler Across Three Databases: The Critter Stack Since August 2ndSixty-three releases in sixteen days across Marten, Wolverine, Polecat, Fisher, Weasel, and the shared JasperFx libraries. Fisher brings event sourcing and document storage to SQLite with no server at all, the shared contracts wave means the same Wolverine handler now runs on PostgreSQL, SQL Server, or SQLite without naming a store, and a projection loader bug that silently skipped events makes this an upgrade you should not sit on.14th August 2026What a Critter Stack Workshop Actually Looks LikeWe've run Critter Stack workshops for several teams now, and no two have been the same. One went deep on asynchronous messaging, another on Wolverine's HTTP endpoint and message handler hybrids, a third on using Marten projections to build denormalized views for reporting screens. The material is built and ready — what it turns into depends on what your team actually needs.11th August 2026Event Sourcing Without the Eventual Consistency Tax: Strong Consistency Options in Marten and PolecatMost event sourcing stacks make eventual consistency mandatory: events in one database, read models in another, and a subscription in between. Marten and Polecat keep events and read models in one database, which unlocks a dial no one else offers — projections snapshotted in the same transaction as the events, FetchLatest reads that are accurate even with async projections, wait-for-non-stale queries, and test automation that makes asynchronous projections actually testable.5th August 2026Metadata All the Way Down: Correlation, Causation, and Headers Across Wolverine, Marten, and PolecatEvery serious event sourced system eventually needs to answer 'what caused this event, and who did it?' The Critter Stack establishes correlation, causation, saga, user, and tenant metadata on Wolverine message envelopes — seeded straight from OpenTelemetry activities — then relays all of it onto the events Marten and Polecat store, with storage you can dial from lean to rich.27th July 2026Announcing CritterWatch 1.0 RC 1The first release candidate for CritterWatch 1.0 — a purpose-built monitoring and operations console for the Critter Stack that shows you the system you actually shipped, watches it for you, hands your AI assistant a real control surface, and gives you a proper cockpit for the event store.21st July 2026Never Skip an Event: Hardening Marten's High Water DetectionA deep look at the recent hardening of Marten's async projection high water detection -- why an in-flight transaction gap is dangerous, and how transaction evidence keeps projections from ever silently skipping an event.11th June 2026Polecat: A SQL Server-Native Event Store and Document DatabasePolecat is an event store and lightweight document database for .NET, backed by SQL Server 2025. It brings the proven Marten development model — same IDocumentStore API, projections, and async daemon — to SQL Server shops without a database migration.22nd March 2026Announcing Polecat: Event Sourcing with SQL ServerPolecat is a new JasperFx library that brings Marten's proven Event Sourcing and document database model to SQL Server 2025 — the best technical option for Event Sourcing with SQL Server in .NET.13th December 2023Practical Introduction to Event SourcingOskar Dudycz's webinar for anyone interested in Event Sourcing but unsure where to start.15th November 2023The Critter Stack at .NET 2023Jeremy's .NET 2023 talk on CQRS with Event Sourcing using Marten and Wolverine: lower code ceremony, a great local developer story, testable domain logic, and built-in diagnostics.30th July 2023CQRS is Easier than You Think!Oskar Dudycz's talk on why CQRS does not have to be scary, and how the Critter Stack keeps it approachable on .NET.27th July 2023Marten as Event StoreMarten pairs its document database with a full event store on PostgreSQL. A short orientation, with pointers to the CoDe Magazine article and Oskar's NDC Oslo 2023 talk.