Hot Platform
The Hot Platform is a complete backend workflow automation system. It combines a purpose-built programming language with managed infrastructure for running, monitoring, and scaling your workflows.
Start with the Platform Execution Model to see how events, handlers, runs, tasks, retries, workers, and streams fit together.
Architecture Overview
Core Concepts
Runs
A run is one tracked, top-level function execution attempt initiated by the platform. Function calls inside that execution remain part of its trace rather than creating additional runs. Each run has:
- Unique run ID for tracking
- Full execution trace
- Input parameters and return values
- Timing and performance data
- Error details if failed
Events
Events are the primary way to trigger asynchronous workflows. Emit events from your application or external systems, and Hot automatically routes them to registered handlers.
// Define an event handler
on-user-signup meta {on-event: "user:created"}
fn (event) {
send-welcome-email(event.data.email)
create-default-settings(event.data.id)
}
Streams
Streams correlate related events, runs, retries, and tasks into one execution history. The same stream ID also supports live run notifications and user-emitted data for AI responses, progress updates, and other interactive work.
Tasks
Tasks are long-running asynchronous resources started by runs or other tasks. They inherit the current stream and are linked to the run that started them. Task execution is also represented by a task-type run.
Workers
Workers are the execution engine of the Hot Platform. They consume queued events and tasks, execute Hot code or containers, and report results back.
- Scale horizontally by adding more workers
- Process event handlers and scheduled jobs
- Execute in isolated contexts for security
Platform Components
| Component | Purpose |
|---|---|
| Hot API | API for executing functions, sending events, and managing files |
| Workers | Execution engine for running Hot code |
| Alerts | Monitor your applications with notifications for run failures, deployments, and custom events |
| MCP Services | Expose Hot functions as MCP tools for AI agents |
| Webhooks | Turn Hot functions into webhook endpoints for external services |
| Custom Domains | Map your own domain names to your Hot Dev environment |
| Hot App | Real-time monitoring and debugging interface |
Deployment Options
Hot Cloud (Managed)
Deploy to the Hot Cloud with a single command:
hot deploy
Hot Cloud provides:
- Managed workers with auto-scaling
- Global edge deployment
- Built-in observability
- Zero infrastructure management