NATS and JetStream on your Mac.
Embedded server. No CLI.
The native macOS app that does NATS pub/sub, an embedded server, JetStream streams and consumers, Key-Value and Object stores, and protobuf payload decode — in one window. No Docker. No nats-server daemon. No Electron.
Screenshots
See it in action
Start the embedded NATS server with one click, then publish and subscribe with wildcard subjects and headers. Watch messages arrive in real time.
Create and inspect streams, browse stored messages, and manage durable consumers with pending and redelivery stats.
Browse Key-Value buckets and keys with history and live watch, and upload or download files from the Object store.
01: Features
A full NATS toolkit. One native window.
Pub/sub, an embedded server, JetStream, KV, Object store, schema-aware payload decode, and server monitoring — all in one native macOS app. No subscriptions. No Electron. No JVM.
Pub / Sub Client
Connect to any NATS server. Publish messages and subscribe with wildcard subjects (* and >). Full message header support, request/reply, and queue groups.
Embedded NATS Server
Start and stop a real NATS server from the GUI for local development and demos. No Docker container, no nats-server binary, no daemon to configure. Click Start and you have a broker.
JetStream Streams
Create, inspect, purge, and delete streams. Browse stored messages with sequence, subject, and timestamp. Export a stream's messages to CSV for offline analysis.
JetStream Consumers
Create durable and ephemeral consumers, fetch the next message, acknowledge, and watch pending counts, ack-pending, and redelivery metrics. Debug pull and push consumers without the CLI.
Key-Value Store
Manage KV buckets and keys: get, put, delete, and revision history. Live-watch a key or a whole bucket and see value changes the instant they land.
Object Store
Browse Object store buckets. Upload files from disk, download objects back, put an inline payload, and list or delete entries — large blobs chunked over JetStream, no extra service.
Protobuf Schema Registry
Import .proto files and bind subject patterns to a protobuf message. Messages on matching subjects decode into readable JSON automatically — you see fields, not hex.
Payload Viewer
Auto-detect JSON, protobuf, or raw bytes. Pretty-print JSON, render bound protobuf messages as fields, and fall back to a hex/string view for everything else.
Server Monitor ($SYS)
Subscribe to $SYS.> for live server stats, connections, accounts, and slow-consumer alerts. Pretty-printed JSON so the monitoring stream is actually readable.
02: Compare
How it compares to the usual NATS workflow
Inspecting NATS today means the nats CLI plus nats-server in Docker, or a web playground. Here's how that stacks up against a native app.
03: Use Cases
Built for NATS developers on macOS.
Microservice messaging, event streams, edge IoT, and protobuf contract testing — inspect and debug it all without leaving your Mac.
Microservice Messaging
Subscribe to orders.* and payments.* across services. Watch the full message flow with headers and payloads, catch missing fields before they hit production.
JetStream Debugging
A consumer not acking? Inspect the stream, fetch the next message, and read pending and redelivery counts. Purge and replay without dropping into the CLI.
Local Development
Run the embedded server, point your apps at nats://localhost:4222, and develop against real JetStream, KV, and Object stores — no Docker Compose file to maintain.
Protobuf Contract Testing
Import your .proto, bind subject patterns, and verify every published message decodes cleanly. Spot schema drift between producer and consumer the moment it ships.
Config & State Inspection
Browse a KV bucket of feature flags or shared config, watch a key for live changes, and read revision history to see who flipped what and when.
Edge IoT Messaging
Bridge device telemetry over NATS at the edge. Monitor $SYS.> for connection drops and slow consumers, and decode protobuf sensor payloads inline.
One-time purchase
The NATS tool your Mac has been missing.
04: FAQ
Common questions
nats-server binary, no CLI. Click Start and your local NATS — with JetStream — is running for development and demos.nats:// or wss://), with TLS and credential or JWT authentication. Works with Synadia Cloud, a self-hosted cluster, or the embedded local server..proto files, then bind a subject pattern (e.g. orders.*) to a protobuf message. Messages on matching subjects are decoded into readable JSON automatically instead of raw bytes, so you see fields, not hex.nats-server daemon to configure. Install the app and you have a full NATS + JetStream environment.Stay Updated
Get notified about new features & schema support
We add schema formats, JetStream tooling, and platform support regularly. No spam, only product updates.
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