Technical teams frequently struggle to keep software architecture diagrams synchronized with evolving codebases and documentation repositories. Atlantis Diagrams delivers a unified self-hosted workspace that couples code-driven Mermaid.js diagramming with structured Markdown knowledge bases in a responsive web interface. Engineers can compose flowcharts, sequence diagrams, state machines, entity-relationship models, and Gantt schedules using split-view CodeMirror editors with real-time SVG rendering. An integrated version history tracker automatically captures revision checkpoints across the last 15 document states, letting authors compare modifications and restore previous iterations without data loss. The linked notes environment supports rich Markdown editing, LaTeX mathematical formulas, interactive task checklists, tag indexing, and full-text keyword searches across personal documentation libraries. Canvas controls allow users to pan, zoom, inspect individual nodes, and export finalized graphics directly into vector SVG, high-resolution PNG, or printable PDF documents. Storage engines adapt to deployment scale, running on zero-configuration SQLite databases out of the box with optional PostgreSQL, MySQL, and Redis caching layers for high-concurrency environments. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Half the architecture sketches on the internet trace back to Excalidraw - the MIT-licensed virtual whiteboard whose hand-drawn aesthetic made technical diagramming feel approachable, at roughly 85,000 GitHub stars. The infinite canvas offers rectangles, ellipses, diamonds, arrows with smart binding and labels, free-draw, text, images, and an eraser, with full undo/redo, zoom, dark mode, and keyboard-first ergonomics. Community shape libraries add thousands of pre-built elements - AWS architecture icons, flowchart stencils, UI wireframe kits - and everything exports to PNG, SVG, the clipboard, or the open .excalidraw JSON format that keeps drawings diffable and portable. Live collaboration works on a share-a-link model with live cursors and a laser pointer for presenting, and it is end-to-end encrypted by design: the room key travels in the URL hash, which never reaches the server, so the WebSocket relay only ever sees ciphertext. The architecture is remarkably light - the app is a static bundle served by Nginx, drawings persist locally in the browser, and the stateless excalidraw-room relay handles multiplayer - so a self-hosted deployment gives unlimited boards and collaborators with near-zero resource cost, replacing per-editor whiteboard subscriptions.

draw.io is a free, browser-based diagramming editor for flowcharts, network maps, UML models, and org charts, with nothing to install. An infinite canvas takes shapes from extensive libraries, connectors reroute automatically as shapes move, and ready-made templates replace the blank page. Tables, swimlanes, layers, and tags keep large diagrams tidy, and shape metadata and placeholders attach tooltips, links, and translations. Auto-layout straightens flowcharts and trees. Math typesetting, a simple whiteboard layout, and adaptive dark mode are built in, and custom shape libraries carry your own in-house icon sets. Export to PNG, JPEG, WebP, SVG, HTML, or PDF, embed the diagram data inside PNG and SVG files so they stay editable, or save the full diagram as a .drawio file. Your server stores no diagrams: files go to the user's device, the browser, or Google Drive, OneDrive, and GitLab once you register your own OAuth app. Optional AI diagram generation uses your own provider key, and environment variables set the interface language, fonts, and security policy. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache-2.0 licensed.

ExcaliDash adds persistent storage, access control, version history, and real-time collaboration to Excalidraw, transforming ephemeral whiteboarding sessions into a managed drawing library your team can rely on. The Node.js/Express backend with React/TypeScript frontend deploys via Docker Compose on port 6767, using Prisma ORM on SQLite for all drawings, users, and metadata. WebSocket-powered collaboration lets multiple users edit the same canvas simultaneously with live cursor presence. Drawing snapshots preserve every revision with visual preview and one-click restore to any previous state. Three authentication modes handle different deployment needs: local email/password for personal use, hybrid mode mixing native credentials with OIDC for gradual enterprise adoption, and enforced OIDC-only for organizations requiring SSO through providers like Authentik or Keycloak. Scoped sharing controls determine whether drawings stay private, shared internally with team members, or accessible via external links without authentication. Collections organize drawings through drag-and-drop grouping, full-text search locates any diagram instantly, and exports use the non-proprietary .excalidraw format ensuring complete data portability. 1,350+ stars since November 2025. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

Paste one SQL query result into a browser and get an interactive entity-relationship diagram instantly, with no installations, no credentials, and no account required. ChartDB's "Smart Query" runs a single statement in your existing database client that exports table definitions, relationships, indexes, and column types as JSON metadata, meaning the application never touches your database passwords. The canvas renders draggable entities with cardinality markers, collapsible grouping areas, and sticky notes for documentation. AI-powered DDL export generates migration scripts between dialect pairs like PostgreSQL to MySQL or SQLite to CockroachDB, analyzing your schema to produce target-specific DDL with correct type mappings and constraint translations. Import paths cover Smart Query JSON, raw DDL scripts, and DBML files from tools like dbdiagram.io. The AI layer connects to OpenAI or any compatible inference server including local vLLM instances running models like Qwen2.5-32B. Database coverage includes PostgreSQL (with Supabase and Timescale extensions), MySQL, SQL Server, MariaDB, SQLite (with Cloudflare D1), CockroachDB, ClickHouse, and Oracle. Exports to SVG with inline styles or SQL DDL in any target dialect. Ships as a React/Vite frontend behind Nginx in Docker, deployable on RepoCloud with dedicated VPS resources under the AGPL-3.0 license.

Schema design with no account and a few clicks: drawDB is the browser-based entity-relationship diagram editor and SQL generator - an AGPL-3.0 React project with over 37,000 GitHub stars. Draw tables with columns, data types, defaults, and constraints; connect fields to create foreign-key relationships; group tables into labeled subject areas; and annotate with notes. When the design is ready, one export produces CREATE TABLE DDL - with constraints, indexes, and foreign keys - targeted at MySQL, PostgreSQL, SQLite, MariaDB, SQL Server, or Oracle. Diagrams can be database-specific, unlocking every native type plus dialect features like PostgreSQL enums and composite custom types, or generic for portability across all supported flavors. The reverse direction works too: paste existing DDL into the import dialog and drawDB renders your live schema as a navigable diagram - the fastest way to document an inherited database. Versioning and migration-script generation track schema evolution, full editor ergonomics (undo/redo, copy/paste, duplicate, themes) keep iteration fast, and diagrams export as PNG, SVG, or shareable JSON. Everything runs client-side against browser storage - no backend database connection needed - so the self-hosted Docker deployment is a featherweight static app that keeps proprietary schema designs entirely on your infrastructure.

Inheriting a sprawling database with hundreds of undocumented tables usually means weeks of guesswork, unless you open it in Azimutt to visually map schemas, trace relationships, and inspect live rows in one workspace. Instead of dumping every table onto a cluttered canvas that crashes your browser, the visual explorer starts clean so you can search across entity names, column types, and SQL comments to reveal only the tables relevant to your investigation. Clicking foreign-key or primary-key indicators expands incoming and outgoing relations step by step, while the graph path-finder automatically calculates the shortest join route between any two distant entities. When debugging production issues or answering support tickets, you can query live records across PostgreSQL, MySQL, MariaDB, SQL Server, Oracle, SQLite, MongoDB, Couchbase, Snowflake, and BigQuery, then click directly through foreign keys in the result rows to follow data lineage visually. Architects and developers also design new schemas at typing speed using Azimutt Markup Language (AML), attach contextual markdown notes, tags, and memos to saved layouts for team onboarding, and run automated schema analysis that flags missing primary keys, implicit foreign keys, inconsistent column types, and oversized tables. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

To design relational database schemas visually and generate production-ready SQL migrations without writing boilerplate DDL by hand, developers use StackRender, an interactive browser-based schema modeling studio. Users can start from a blank drag-and-drop Entity Relationship Diagram canvas or import existing SQL DDL scripts directly from PostgreSQL, MySQL, MariaDB, SQLite, Oracle, and Microsoft SQL Server databases. Each table node provides granular control over column data types, lengths, precision, character sets, collations, nullability, uniqueness, primary keys, composite indexes, and custom PostgreSQL enum types. When connecting tables across one-to-one, one-to-many, and many-to-many relationships, the schema analyzer checks for circular foreign key dependencies and suggests performance indexes on frequently joined columns. As a schema evolves over time, the visual state-diff engine records every structural modification and generates paired UP forward-migration and DOWN rollback scripts, accurately translating table and column renames into non-destructive ALTER statements rather than dropping and recreating data. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

Turning chaotic group brainstorming sessions into structured visual diagrams, TeamMapper provides a real-time collaborative mind mapping workspace that teams and classrooms can join instantly without creating user accounts. Workshop facilitators, teachers, and product squads start from a central root topic and branch outward into hierarchical radial trees, using keyboard shortcuts and full undo-redo history to capture ideas at the speed of conversation. Every node can be styled with custom branch and background colors, adjustable font weights and sizes, external reference links, uploaded raster images, and visual pictograms from the ARASAAC library to reinforce memory and visual association. Sharing a live session takes a single click: hosts distribute either a view-only link, a full modification invite URL, or a scannable QR code so remote colleagues and students in the same room can edit branches simultaneously. When enabled by the administrator, an integrated AI assistant can automatically generate initial mind map branches and subtopics from a text prompt to jump-start planning sessions. Completed maps export cleanly to JSON, Mermaid diagram syntax, scalable SVG vectors, high-resolution PNG images, or printable PDF documents, and existing JSON maps can be re-imported at any time for follow-up workshops. Built-in privacy controls automatically purge inactive mind maps and orphaned image attachments after a configurable retention window, simplifying GDPR compliance for schools and enterprises. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

A Node.js server, a large shared canvas, and a URL - WBO (Whiteboard Ophir) is collaborative whiteboarding reduced to its essence. There are no accounts and no setup - to collaborate, you send someone the board's link, and every stroke appears for all connected users in real time over WebSockets, with cursor positions shared so you can see where collaborators are working. Board state persists automatically and continuously, so a diagram drawn in today's lesson is still there next week at the same URL. Boards come in three flavors: a public free-for-all, private boards with random unguessable names, and named boards with custom URLs shared by anyone who knows the name. The tools cover teaching and brainstorming needs - pencil, straight lines, rectangles, ellipses, text annotations, eraser, a full color palette with brush sizes - and boards export as SVG or PNG. Despite the simplicity, the server is production-minded: JWT authentication gates board access with granular capabilities (open, edit, and clear as separate permissions), rate limiting caps per-client message volume, reverse-proxy and subpath deployment are supported, and OpenTelemetry provides metrics, logs, and traces. It works on tablets and touch devices, speaks multiple languages, and consumes minimal resources. AGPL-licensed.

The drawing surface inside WebRTC conference tools like Meetzi and the LAMS online-learning platform is Whiteboard (by cracker0dks) - a lightweight Node.js collaborative sketchboard built to be embedded and customized, which also slots into Nextcloud via the External Sites app. Everyone opening the same whiteboardid URL parameter draws on the same board, with remote user cursors visible live, per-user undo/redo, and an indicator showing the smallest participating screen so nobody draws outside a colleague's view. Content handling goes beyond pen strokes: drag-and-drop or paste images and PDFs from any PC or browser, then resize, rotate, and draw over them on canvas or background; add text and sticky notes; hold Shift for angle-snapped lines and perfect squares. Every function has a keybinding - deliberately friendly to pen displays like Wacom and XP-Pen whose hardware buttons map to shortcuts. Boards save to image or JSON (with reload), export directly to Nextcloud via WebDAV, and persist across restarts with the file-database option. A REST API with bundled interactive docs allows full programmatic control, an optional access token locks down uploads, and YAML configuration tunes behavior and performance. MIT-licensed and reverse-proxy friendly.

Scattered browser tabs, buried wiki folders, and disconnected issue trackers fragment engineering context across too many tools, which is why Ideon unifies your repositories, notes, and tasks on a shared infinite canvas. Rather than forcing projects into rigid folder hierarchies, you arrange interactive blocks spatially on a two-dimensional map where related documents, checklists, calendar schedules, and code references sit right beside one another. Teams can embed live repository cards and open issue streams directly from GitHub, GitLab, Gitea, and Forgejo onto the workspace, keeping code status visible alongside architecture documentation. Rich content blocks render Markdown notes with threaded comments, Mermaid flowcharts, uploaded files, images, and bookmarked links on the same board. Real-time multiplayer collaboration lets teammates edit blocks simultaneously, follow live cursors across the canvas, and map system designs together without edit conflicts. Built-in Time Travel snapshots capture historical states of the workspace so you can scrub backward to review how a project evolved or trace past design decisions. You can even synchronize an entire project canvas directly to a Git repository, storing notes and spatial block layouts as versioned files. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.