Run
Immutable execution plan
Open docs →● FastSim vNext · Alpha
Turn robot simulation into an inspectable, reproducible application
FastSim composes configuration, registries, scenarios, plugins and UniRoboSim backends into one deterministic run that can be validated and locked before physics starts.
git clone https://github.com/FastSim-Benchmark/FastSim.gitConfiguration to runtime
A complete simulation application runtime
Core owns stable lifecycle and capability boundaries. Tasks, models, teleoperation and data products remain plugins.
Registry
Traceable component resolution
Open docs →Scenario
Scene, behavior and evaluation boundaries
Open docs →Plugins
Scoped services and control arbitration
Open docs →UniRoboSim
Portable multi-backend simulation
Open docs →Developer experience
Inspect, script and serve the same compiled run
The CLI, Python API and optional Server all operate on the same compiled execution plan.
Validate and explain
Validate and explain
Locate field provenance and diagnostics before launch.
Learn more →TERMINAL
fastsim config validate examples/quickstart/run.yaml --json
fastsim config expand examples/quickstart/run.yaml
fastsim config explain examples/quickstart/run.yaml runtime.physics_hzTERMINAL
fastsim config lock examples/quickstart/run.yaml --output quickstart.lock --json
fastsim config verify-lock quickstart.lock --jsonPython application API
Python application API
Control embedded applications through the same lifecycle.
Learn more →TERMINAL
import asyncio
import fastsim
async def main():
async with fastsim.app("run.yaml") as simulation:
await simulation.start()
print(await simulation.control.targets())
asyncio.run(main())HTTP Server
HTTP Server
Expose async run, control and scene operations through an optional plugin.
Learn more →TERMINAL
fastsim-server examples/quickstart/run.yaml --host 127.0.0.1 --port 8000
curl http://127.0.0.1:8000/health/ready
curl http://127.0.0.1:8000/api/v1/capabilitiesConfiguration
Configuration is more than a parameter file
It is an application declaration resolved, validated, locked and traced before runtime.
schema · backend · runtimeRun
A top-level boundary and source in the run declaration.
registries · trust · cacheProject
A top-level boundary and source in the run declaration.
scene · behavior · evaluationScenario
A top-level boundary and source in the run declaration.
component://Registry
Resolved at compile time into the immutable plan.
plugin://Plugins
Resolved at compile time into the immutable plan.
object://Objects
Resolved at compile time into the immutable plan.
robot://Robots
Resolved at compile time into the immutable plan.
sensor://Sensors
Resolved at compile time into the immutable plan.
sha256Resources
Resolved at compile time into the immutable plan.
fastsim-lock/1Lock
Resolved at compile time into the immutable plan.
artifactsOutputs
Resolved at compile time into the immutable plan.
Extensibility
Add product capabilities without changing Core
Each plugin receives only the scoped services and control authority declared by its manifest.
Manifest
Declare capabilities, avoid implicit imports
Package manifests participate in discovery, resolution and locking.
Scoped Services
Least-authority runtime services
Observation, geometry, control and output services are granted by declaration.
Recordplugin
Replayplugin
Serverplugin
Visualizerplugin
TUIplugin
MCPplugin
Missionplugin
Modelplugin
Teleopplugin
Agentplugin
Debugplugin
Customplugin
Advanced
Capability boundaries for real robotics workflows
01
Lock & reproduce
Content-addressed locks, pinned inputs and atomic outputs make a Run auditable.
02
Control arbitration
Authority, priority and cancellation let multiple control sources share one runtime.
03
Atomic observations
WorldState and Observation are read from the same committed tick.
04
Planning geometry
Stable queries expose collision worlds, frames and geometry snapshots.
05
Pluggable kinematics
Solvers connect through a separate SPI with explicit capability reporting.
06
Realtime media
On-demand camera streams and Server sessions stay outside the core path.
07
Output integrity
Staging, validation, atomic publication and cleanup protect run artifacts.
Backend architecture
Core, UniRoboSim and physics providers have distinct jobs
APPLICATIONFastSim Core
Run · Plan · Lock · Lifecycle
PORTABLE APIUniRoboSim
Scene · State · Control
PROVIDERSIsaac Lab · MuJoCo
Native physics & rendering
PROVIDERPyBullet · Custom
Project-specific capability
Start with a verifiable Run
Inspect configuration without a simulator, then choose the Provider your project needs.
Get started →