Aliot SysML v2

Model as code. See the system.

Edit SysML v2 as text and diagrams. Built-in validation and AI tools.

Write .sysml and .kerml models with completion, navigation and diagnostics. Explore and edit the same model through graphical views. The OMG standard library is included. No Java or PlantUML is required.

User guide · Sample models · Website · Report an issue

Captured from Aliot 0.45.0 running in VS Code. View the light screenshot, dark screenshot or editing captures.

Edit the diagram. Update the model.

Use Properties and diagram context menus to add elements, rename them, change values and create supported relationships. Semantic edits are written back to the source. The source and saved layout work with Undo, Redo, Save All and Git.

Edit inherited values and port features

Change an inherited value to create a local override. Here, battery capacity changes from 80 to 95. The Battery definition and spare battery stay at 80. Inspect a port to edit conjugation and directed features.

Navigate the model hierarchy

Choose the Diagram pill beside a Browser element to focus its diagram. Use Up beside the filter to return to the parent's General View.

Get started

1. Open a .sysml or .kerml file, or run SysML: New Model….
2. Wait for the status bar to show SysML: ready.
3. Use Ctrl+Space for completion, or type sysml- for model snippets.
4. Run SysML: Show Diagram, use the editor's diagram button, or choose the Show diagram CodeLens above a supported element.
5. Right-click the canvas or Browser pane to add elements. Select an element to edit its Properties.

Explicit standard view usages open the matching diagram mode on their exposed container. BrowserView reveals the Browser pane. This is a shortcut to the existing editor; custom view filters and renderings are not evaluated.

Use the diagram Save button or File > Save All to save source and layout together. Auto Save also works.

Start with the small rover, then explore the drone or software-defined vehicle.

Modeling support

• Language intelligence: highlighting, completion, hover, signature help, formatting, references, rename and go-to-definition.
• Validation: syntax, name resolution, semantic, unit and style diagnostics, with quick fixes for supported cases.
• Standard library: bundled SysML v2 and KerML definitions, quantities and units. Navigate into read-only library source.
• Optional imports: enable sysml.editor.autoImportOnSave to add unambiguous workspace imports when saving.

Views for different questions

The Browser pane provides model navigation and authoring alongside diagrams. Its eye buttons hide or show single elements on the open diagram. Run SysML: Which Diagram? for help choosing a view.

Diagrams support automatic layout, manual placement, connector routing and SVG export. Grid View supports CSV export. Layouts are stored under .vscode/sysml/diagrams/ and can be committed with the model.

AI tools for your chosen agent

Aliot contributes model-context, draft-validation, library-search, symbol-resolution, requirement-trace and diagnostic-explanation tools to compatible VS Code AI agents.

Tools use the language server's model information. They do not provide an AI model or credentials. Configure a compatible agent separately; core modeling needs no AI account. Context shared with an agent is handled under that service's policies.

Desktop, browser and themes

Language services and editable diagrams work in desktop VS Code, vscode.dev and github.dev. Opening .kpar archives, abstract-syntax JSON interchange, revealing local library folders and running the companion CLIs require desktop or Node.js access.

Choose Aliot Dark or Aliot Light in Preferences: Color Theme. These are the renamed SysML v2 Default and SysML v2 Gray themes. Existing settings keep working through the stable SysML v2 Default (dark) and SysML v2 Gray (light) identifiers. Diagrams follow the active editor theme, including high contrast.

Validate and export in CI

The companion tools run in Node.js environments:

npx sysml-validate models/ --strict
npx sysml-validate models/ --format github
npx sysml-diagram export --file model.sysml --view iv --out docs/iv.svg

sysml-validate supports text, JSON, SARIF and GitHub output. sysml-diagram can reuse saved layouts. Run SysML: Copy Headless CLI Command for the current model. See the guide for options.

Settings and help

Open Settings > Extensions > SysML v2 for validation profiles, auto-import, diagram refresh and presentation options. The default diagram refresh mode is live; auto-import on save is opt-in.

This project is under active development. Report a problem with a small model, extension version and view name. Read the release notes for recent changes.

Privacy and licenses

Aliot collects no telemetry and includes no analytics. Models and diagram layouts stay in the local or browser workspace unless you choose to share them through another service.

The extension uses the Freeware License. The bundled OMG library is from release 2026-05 and retains its EPL-2.0 license and notices. Langium, React, React Flow and the VS Code language-server libraries use MIT; Chevrotain uses Apache-2.0; Eclipse Layout Kernel uses EPL-2.0. Full third-party notices are included with the package.

_{Architecture, Language, Integration, Orchestration, Traceability. The ideas behind the Aliot name.}