What makes it different
Not a diagram tool.
A running system.
Most system design tools let you draw boxes and arrows. FlowFrame actually runs the logic, captures every hop, and plays it back so you can see what's happening inside.
Run real simulations
The engine actually runs your distributed system. Requests hop from Client → Load Balancer → Server → Redis → Postgres — not just drawn arrows.
Frame-by-frame playback
Every request hop becomes a playback frame. Pause at any moment, scrub backwards, or fast-forward. See exactly what happened and why.
Inspect node state
Open any node's inspector. See Redis key snapshots, server load, capacity, request queues — all updating live as the simulation runs.
Learn as you simulate
Each concept has a guided doc page with a live sim embedded. Read the theory, trigger the failure, watch the recovery — all on one screen.
Supported in v1
4 SCENARIOSPick a scenario. Hit play.
Each scenario is pre-wired with real engine logic. Just select one and watch the architecture run.
Load Balancing
Watch Round Robin and IP Hash distribute requests across 3 servers. Drag capacity to 0 to see failover in action.
Cache-Aside
Three deterministic requests: cache hit, cache miss → DB fallback, and invalid key. See Redis snapshots update frame-by-frame.
API Gateway
Path-based routing with server pools. Set a server's capacity to 0 and watch the gateway return 503 automatically.
Valet Key Pattern
Client requests a signed upload token from the server. Server issues it. Client uploads directly to cloud storage — no proxy.
Interactive Docs
Guided learning for each distributed system concept — theory on the left, live simulation on the right. Read the explanation, trigger the scenario, watch it run.
Custom Sandbox
Drag & drop any component — Clients, Load Balancers, Servers, Redis, Postgres, API Gateways — and wire up your own topology. Then run it.
What's supported right now
✓ Supported
- ✓Round Robin load balancing
- ✓IP Hash load balancing
- ✓Capacity-based server failover
- ✓Cache-Aside pattern (Redis)
- ✓Database fallback (Postgres)
- ✓API Gateway path routing
- ✓Valet Key token issuance
- ✓Frame-by-frame playback
- ✓Node state inspector
- ✓Custom sandbox canvas
- ✓Interactive learning docs
- ✓Dark / Light mode
⏳ Coming next
- ○More LB strategies (Least Conn, Weighted RR)
- ○Circuit Breaker & Retry patterns
- ○Saga / distributed transaction flows
- ○Message Queue simulations (Kafka, RabbitMQ)
- ○Multi-region & CDN scenarios
- ○User-shareable scenario links
Ready to see your architecture run?
Pick a scenario, hit play, and watch every hop of every request — live.