Design is everything.

On your PC, as local XML text files. Nothing is stored in the cloud. Because it's text, you can version, diff and branch it directly with Git.

No. The AI Co-Pilot runs an on-device LLM (llama.cpp, with Llama-3.2-3B-Instruct bundled). Your diagrams and prompts are never sent to an external server.

Yes. You can try every feature for free with no sign-in — draw, model, explore and ask the AI at no cost. There is no permanent free version: a $10/month subscription is required to save (persist) your models and nodes to local files.

Yes. Purchase and cancellation happen through Stripe's hosted Checkout and Customer Portal in your browser. You can cancel yourself anytime; the app never stores your payment details.

Draw+ is built specifically for individual developers. It does not provide team management, co-editing, organization accounts or RBAC. It's a simple, single account for one person working locally.

Yes. The UI is bilingual English / Japanese — menus, context menus and dialogs all follow the language switch in Settings.

SysML V2 (bdd / ibd / pkg / par / act / sd / stm / uc / req / test — 10 types) plus UML, BPMN, mind maps and basic shapes, all on the same canvas.

No. Draw+ is a Win32 + Direct2D native app — not Electron — so it's light and launches instantly. A C++ core engine keeps large models smooth to edit.

MBSE (Model-Based Systems Engineering) is an engineering approach that uses formal models — rather than documents alone — as the primary artifact throughout a project lifecycle. A specialized tool matters because it enforces correct SysML notation, maintains live traceability between requirements, models, and tests, and can simulate behavior directly on the model. Draw+ for Windows covers SysML V2 modeling, requirements traceability, simulation, and on-device AI assistance in a single local-first Windows app for $10/month.

Draw+ for Windows and IBM Rhapsody both support SysML V2 modeling and requirements traceability, but differ sharply in cost, deployment, and scope. Rhapsody and Cameo are enterprise suites priced in the tens of thousands of dollars per seat per year; Draw+ is a flat $10/month with no per-seat pricing. Rhapsody requires cloud connectivity or large enterprise infrastructure; Draw+ is fully local-first and works in air-gapped environments. Draw+ is designed for individuals, small teams, and engineers who need affordable local MBSE without a multi-year procurement process.

SysML V2 (Systems Modeling Language version 2) is the latest OMG standard for systems engineering modeling. It replaces SysML 1.x with a cleaner, text-first kernel called KerML, and defines 10 diagram types — Block Definition (bdd), Internal Block (ibd), Package (pkg), Parametric (par), Activity (act), Sequence (sd), State Machine (stm), Use Case (uc), Requirement (req), and Test (test) — each targeting a specific aspect of system design. Draw+ for Windows natively implements all 10 SysML V2 diagram types with a methodology-aware palette and validation.

Draw+ provides requirements-to-test traceability and verification coverage reporting directly relevant to safety-critical workflows under ISO 26262, DO-178C, IEC 62304, and similar standards. The application itself is not a certified or qualified tool; using it in a formal certification context requires your organization to perform tool qualification independently. That said, Draw+ can help you build and maintain the requirements, model, and trace structure those standards require — including Satisfy and Verify links, gap analysis, and Git-versioned model history.

The AI Co-Pilot runs a quantized local language model on your Windows PC. When you type a natural-language prompt — for example, 'Create an activity diagram for a login flow' — the model generates SysML V2 nodes and links and places them on the canvas automatically. Because everything runs locally, your prompts, diagrams, and design data are never sent to any external server. This makes the AI Co-Pilot safe for confidential projects and air-gapped environments.

Draw+ saves models as KerML-compatible XML text files. The format is human-readable, so you can open model files in a text editor, diff them with standard tools, and commit them directly to Git. Version history, branching, and merging of design models work exactly like source code — no proprietary binary format and no cloud sync required.

Yes. Draw+ is designed for local-first use. After installation, the application runs entirely without network access — modeling, simulation, AI assistance, and file saving all work offline. The subscription status is cached locally, so brief connectivity is needed only for monthly renewal checks. Day-to-day modeling is fully air-gapped compatible.

Code generation is on the roadmap but is not available in version 1.0.0. The current release focuses on SysML V2 modeling, requirements traceability, three built-in simulators (activity token flow, sequence timelines, parametric constraint solver), and on-device AI. You can export diagrams and models to PNG, JPEG, SVG, and PDF for documentation and client deliverables.

KerML (Kernel Modeling Language) is the foundational semantic layer underlying SysML V2. It defines the core constructs — types, features, relationships, and behaviors — that SysML V2 diagrams are built on. Draw+ stores models as KerML-compatible XML text, which means the file is human-readable, version-controllable with Git, and structured consistently with the OMG standard.

Draw+ for Windows currently runs on Windows 10 and Windows 11 (64-bit). A separate macOS edition (Draw+ for Mac) is available at shokoma.com. Linux support is not currently planned.