Messaging library built on top of NATS JetStream: commands, queries, requests and events with pluggable serialization, OpenTelemetry instrumentation, outbox, sagas, distributed locks, key-value/object stores and caching.

Source, issues and full documentation: https://github.com/MiloszKrajewski/K4os.NatsTransit

Packages

All packages depend on K4os.NatsTransit.Abstractions and are peers, not layers (unless noted):

K4os.NatsTransit — message bus (needs .Serialization)
K4os.NatsTransit.Serialization, .NewtonsoftJson, .GoogleProtobuf — serializers
K4os.NatsTransit.Storage, .Storage.AdoNet — value store / object store (NATS KV, Object Store, SQL)
K4os.NatsTransit.Locking — distributed locks
K4os.NatsTransit.Caching, .Caching.FusionCache — IDistributedCache / FusionCache backplane
K4os.NatsTransit.Outbox, .Outbox.EF — outbox pattern
K4os.NatsTransit.Sagas — stateful long-running workflows
K4os.NatsTransit.HealthChecks, .OpenTelemetry — observability

For AI agents: cheat sheet

Opinionated, recipe-style briefs for bootstrapping a service with these packages ship inside K4os.NatsTransit.Abstractions (every package depends on it), in its doc/cheat-sheet/ folder. Once the package is restored it is in the NuGet global-packages cache:

<global-packages>/k4os.natstransit.abstractions/<version>/doc/cheat-sheet/index.md

If you are reading this file from the cache (<global-packages>/k4os.natstransit.<package>/<version>/README.md), the same file is at ../../k4os.natstransit.abstractions/<version>/doc/cheat-sheet/index.md. Inside the Abstractions package itself it is simply doc/cheat-sheet/index.md.
<version> is the currently referenced version of the package.
<global-packages> is usually ~/.nuget/packages, or the folder in the NUGET_PACKAGES environment variable when it is set. If neither helps, dotnet nuget locals global-packages -l prints the actual location.

Start with index.md, then read only the files matching the packages you use.