Web UI¶

smelt includes a built-in web interface for visualizing your model dependency graph and triggering runs.

Launching the UI¶

smelt ui

By default, the UI is served at http://127.0.0.1:3000.

Options¶

Flag	Default	Description
`--host`	`127.0.0.1`	Host address to bind to.
`--port`	`3000`	Port to serve the UI on.
`--project-dir`	`.`	Path to the smelt project root.

Example with custom host and port:

smelt ui --host 0.0.0.0 --port 8080

Features¶

Dependency graph¶

Interactive visualization of your model DAG using React Flow. See how models connect and identify upstream/downstream relationships at a glance. Click a model node to open its detail panel.

Model detail panel¶

Click any model in the graph to see:

Columns with inferred types and nullability
Upstream and downstream dependencies
Incremental configuration (granularity, partition column, etc.)
Batch safety indicators (green/yellow/red badges)
Diagnostics -- parse errors, type errors, and undeclared column warnings

Run planner¶

Plan runs interactively before executing:

Select models to include (with tag filtering)
Set time range for incremental models
Configure batch size and per-partition execution
Preview the execution plan with per-batch detail before committing

Run execution and monitoring¶

Execute runs directly from the UI with real-time progress:

Progress bars for each model and batch
Live event log streamed via WebSocket
Cancellation -- stop a running pipeline between batches
Run history -- browse past runs with expandable details

Only one run can execute at a time.

Live file watching¶

The UI watches your project files for changes. When you save a model or configuration file, the UI automatically recompiles and updates the graph, diagnostics, and model details -- no manual refresh needed.