Systems engineers model billion-dollar spacecraft, life-saving medical devices, and autonomous vehicles in tools that can't even do a proper diff/merge/version control even with large expensive infrastructure.

I built Sylang to address that.

What is Sylang?

A text-based language for modeling complex systems. Write declarative code, get visual diagrams, traceability matrices, FMEA analyses, and compliance reports automatically. Works with Git, VSCode, and AI code assistants.

Example:

  def requirement BrakeActivation
    description "System shall activate brakes within 100ms"
    safetylevel ASIL-D
    testedby ref testcase EmergencyBrakeTest
    derivedfrom ref safetygoal PreventCollision
    allocatedto ref block BrakeController

This generates:

- Architecture diagrams (decomposition, internal block diagrams) - Traceability matrix (requirement ↔ test ↔ block ↔ safety goal) - Coverage analysis (which requirements lack tests?) - Compliance reports (functional safety, ASPICE, etc.)

Why text-based modeling works:

Your AI code assistant (Cursor, GitHub Copilot, Claude, Gemini) can: - Generate requirements from safety goals - Create test cases from requirements - Draft FMEA analyses from architecture - Refactor across files with semantic understanding - Suggest missing relationships

Git workflows that actually work:

  git diff requirements.req        # See what changed
  git merge feature/new-sensors    # Merge architecture branches
  git blame safety-goals.sgl       # Who defined this safety goal?

No XMI. No database exports. No PowerPoint. Just readable text that generates everything you need.

What you get:

23 file types covering the full engineering lifecycle: - Product lines & variants (.ple, .fml, .vml) - Architecture (.blk, .fun, .ifc) - Requirements & tests (.req, .tst) - Behavioral models (.ucd, .seq, .smd) - Safety analysis (.haz, .sgl, .sam, .flr, .fta) - Dashboards & specs (.dash, .spec) - Automation (.agt, .spr)

All auto-generating visual diagrams: feature models, decomposition diagrams, sequence diagrams, state machines, traceability matrices.

Current state:

- Language stable (v0.9.27) - VSCode extension available (search "Sylang" in Extensions) - Works with Cursor, GitHub Copilot, Claude, Gemini code assistants - Diagram rendering, traceability, coverage analysis working - Solo dev, part-time, building in public

Download at:

https://marketplace.visualstudio.com/items?itemName=balaji-e...

Website: https://sylang.dev

GitHub: https://github.com/balaji-embedcentrum/sylang

Feedback welcome—especially from engineers who've wished their modeling tools worked more like their code editors.