Draw it, write it as code, or hand it to your AI agent: OpenFlowKit is an open-source diagram canvas where the picture and the text behind it are always the same diagram. Drag shapes on the canvas or type a few forgiving lines, and each side regenerates the other as a single undo step. Ten diagram types share that one language: architecture with C4 views and cloud icons, sequence, flowchart, entity-relationship, state, class, mind maps, git graphs, charts, and wireframes. Paste Mermaid, Structurizr, or D2 and it converts into editable shapes, and Copy as Mermaid sends a flowchart or sequence back out for your README. Paste a GitHub repository instead and Map mode draws its architecture for you, with every arrow citing the exact file and line behind it, and a CLI that maps a local checkout for private repos. Connect Claude Code, Cursor, or any MCP client and the agent draws on your live canvas, restyles what is there, and screenshots its own work to check it. A built-in assistant works with your own key from Claude, OpenAI, Gemini, Groq, Mistral, OpenRouter, or a local Ollama, and exports cover PNG, SVG, PDF, JSON, and animated SVG, GIF, MP4, or WebM you can drop into documentation. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

House Planner holds the design of your house in one browser workspace, from true-scale floor plans drawn over a satellite photo of your plot to costed wiring, plumbing, sewer, and heating layouts. Draw walls at true scale in millimetres with thickness and materials, add doors, windows, garage gates, and furniture with true dimensions, and watch room areas and plot coverage total as you work. Flip into 3D for a massing model or the house finished with material textures and facade colours, with cut-down walls for reading the layout from above. Every utility network gets an engineering layer: route sewer lines to a septic tank with slopes and cleanouts, auto-route electrical circuits with breaker and voltage-drop checks, and run water piping from well and boiler to each fixture. Underfloor heating loops lay out room by room, split before 80 metres, and balance flow against heat loss. The bill of materials computes quantities from the plan and networks, producing a priced estimate you can print, tick off as you buy, or export to CSV. Every save is a numbered version with restorable snapshots, tabs cannot overwrite each other, and the JSON plan can be edited by an AI assistant through the same API. One password guards the project, phones get a read-only view for on-site checks, and the whole thing runs in one Docker container with no database. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.