Notes on Windows, macOS, Linux, Android, iOS, and the terminal, synced through your own server: Joplin pairs its open-source clients with Joplin Server, the official self-hosted backend that replaces Dropbox, OneDrive, or Nextcloud as the synchronization target. Notes are Markdown with inline attachments (images, PDFs, audio), organized into hierarchical notebooks and sub-notebooks with cross-cutting tags, alongside to-do lists with reminders and alarms. End-to-end encryption is the headline feature: enabled in the clients, it encrypts sync payloads on-device before upload, so the server stores blobs it cannot read - genuine protection even if the host is compromised. The desktop app offers both Rich Text and Markdown editors, extended by a plugin ecosystem, custom themes, and an Extension API for writing your own scripts; a Web Clipper for Chrome and Firefox captures full pages or screenshots straight into notebooks. Joplin Server ships as a Docker image with SQLite for evaluation and PostgreSQL for production, offers a filesystem storage driver for large content, and includes multi-user support and note sharing - all free under AGPL-3.0 when self-hosted. Notes stay in an open format, so the exit path always exists.

Backed by over 45,000 GitHub stars and described as the tool that replaces Notion, Evernote, and Anki in a single Docker container, SiYuan is the privacy-first knowledge management system where every paragraph, heading, and list item is a uniquely addressable content block. The block-level architecture enables bidirectional links, transclusion embeds, and SQL query blocks that dynamically aggregate content across your entire workspace, while the knowledge graph visualization maps relationship networks between documents and blocks. Built-in databases support table views with relation and rollup columns, filter composition, sorting, and template-based calculations for structured data management alongside freeform notes. The FSRS spaced repetition engine turns any content block into a flashcard with scientifically calibrated review scheduling, eliminating the need for separate memorization tools. AI integration connects to OpenAI-compatible APIs for writing assistance, translation, summarization, and Q&A chat, with semantic search using embeddings and reranking for intelligent content retrieval. The Bazaar community marketplace delivers plugins, themes, templates, and widgets through a managed extension system with TypeScript plugin APIs. End-to-end encrypted synchronization works across S3-compatible storage, WebDAV servers, or SiYuan's own cloud service, while Tesseract OCR extracts searchable text from images and the web clipper captures pages from Chrome, Edge, and Firefox. Export targets include Markdown with assets, PDF, Word, and HTML. 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.

Papyra gives you a calm, private home for notes that stays as easy as sticky notes while quietly linking everything together like a wiki. Cards pin, colour, and drag into place on your desk, and opening one drops you into an editor where slash commands insert headings, checklists, tables, or maps without leaving the keyboard. Type two brackets to link another note, and backlinks gather the other direction automatically, following the note even if you rename it. Notes save themselves, and every earlier version is kept, so you can scrub back through history and restore the draft you actually wanted. Sharing a note lets several people type in it together with visible cursors, comments in threads, and mentions that bring the right person in. Private notes lock behind a PIN or your fingerprint and sit encrypted on disk, while a daily journal page collects the day with a mood and a calendar to browse the year. Search covers notes, to-dos, and attachments with highlighted matches, and image text and audio transcripts can join the index. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.

A notes app that is deliberately not a second brain: notesd keeps your grocery lists, journals, and work notes on a server you run, and syncs them to your phone for fully offline use. The web app and the native Android and iPhone apps each keep a complete local copy, so you can write on a subway and watch everything merge when a connection returns; conflicting edits are combined, or preserved as a linked conflicted copy instead of silently overwriting. Notes are stored as Markdown, so exporting your data or mirroring it to a folder of .md files is always one command away. Tags typed anywhere in a note, including nested ones like #home/garden, collect automatically in the sidebar, and Spaces keep work, personal, journal, and recipes in separate contexts. Full-text search runs across titles and bodies, indexed and ranked both on the server and on your phone. Individual notes can be locked with AES-256-GCM encryption performed on your device, unlocked by password, passkey, or biometrics, while the server only ever stores ciphertext. A few accounts per server, each with its own database, make it easy to host notes for family or friends. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Notes are personal, and Plainpad keeps them that way by running entirely on your own server instead of a vendor cloud. Class notes, trip plans, lyrics, and side-project ideas sit in one fast list that searches instantly and opens in any modern browser, adapting to phones, tablets, and desktops. Added to a home screen it launches like an app, and offline editing keeps writing possible when the connection drops. Turning on encryption stores titles and content encrypted at rest, so even database access does not expose what you wrote. One installation supports unlimited accounts with administrator and user roles, and every person keeps a private notebook no one else can read. There are no note limits, no device limits, no ads, and no tracking of any kind. Moving in is scripted through the built-in REST API, which can import collections from files and other note services into the right accounts. The stack asks only for PHP and MySQL, or a single Docker Compose command, and a sample data seeder can populate a fresh install with realistic study notes for evaluation. Simplicity is the design goal: the interface stays quiet, loads quickly, and leaves the words in front. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL 3.0 licensed.

Standard Notes keeps your notes, files, and tags encrypted on your device before anything touches the network, meaning the server stores only ciphertext it cannot read. Cross-platform sync across desktop, mobile, and web delivers fast, conflict-free updates on unlimited devices with the same zero-knowledge guarantee that only your password can decrypt your content. The V2 server architecture condenses everything into four Docker containers consuming roughly 570MB RAM total (down from 13 containers and 1.7GB in the legacy setup), with startup under one minute. Revision history automatically preserves every version of every note, so recovering deleted text or reverting to a previous state never depends on manual backups. A nested tag system organizes thousands of notes with hierarchical categorization that goes well beyond flat folder structures, while search operates entirely on client-side decrypted content. File attachments of any type encrypt and sync alongside notes with identical end-to-end protection. Multiple editor options span plain text, Markdown with preview, and rich formatting to fit different writing workflows. Two-factor authentication via TOTP with email backup codes adds a second barrier beyond your password. An optional separate container serves the web frontend, providing browser access to your encrypted vault without depending on standardnotes.com infrastructure. With 5,500+ GitHub stars and active development, the project continues expanding editor plugins and sync improvements.

Every line an indentable bullet, every bullet a first-class block that can be referenced, embedded, and queried anywhere: Logseq is a privacy-first, local-first knowledge platform built around the block outliner. The daily journal is the system's beating heart - each day opens a fresh date-stamped page where tasks, meeting notes, and fleeting ideas land as blocks without filing decisions, then connect later through [[wikilinks]] with automatic bidirectional backlinks and ((block references)) that transclude any bullet into any page. Everything persists as plain Markdown or Org-mode files on disk - git-friendly, greppable, and owned forever, with sync via iCloud, Dropbox, Syncthing, Git, or an optional end-to-end encrypted service. Built-in tooling goes beyond notes: TODO/DOING task states with scheduling, native PDF annotation with area highlights, spaced-repetition flashcards, whiteboards for visual thinking, Zotero integration for researchers, and Datalog-powered queries that build dynamic views across the entire graph. A marketplace of hundreds of community plugins and themes adds AI chat, Ollama local-model integration, and custom workflows. Written in Clojure/ClojureScript, AGPL-3.0 licensed with 320+ contributors, and completely free - the local-first Roam for people who refuse subscriptions and lock-in.

For people whose notes number in the tens of thousands, Trilium Notes is the hierarchical note-taking application built specifically for large personal knowledge bases - actively maintained as TriliumNext. Notes arrange into arbitrarily deep trees where every note is both content and container, and cloning lets a single note live in multiple places at once - bash notes belong under both Linux and Scripting, and Trilium refuses to make you choose. A WYSIWYG editor handles rich text, tables, math, and syntax-highlighted code blocks with Markdown-style shortcuts, while dedicated note types cover Excalidraw sketches, mind maps, geo maps with GPX tracks, relation maps that visualize connections between notes, and tables with typed columns. The attribute system is the power layer: labels attach queryable metadata (#year=1999, #author), relations create named links between notes, and both inherit down the tree - feeding full-text search, saved queries, and scripting. Scripting is Trilium's deepest differentiator: JavaScript code notes run on events like note changes or hourly schedules, build custom widgets, and add server-side logic, turning the knowledge base into a programmable platform. Protected notes encrypt sensitive content, note hoisting focuses on subtrees, and the self-hosted server syncs desktop clients across devices.

TriliumNext organizes notes in an infinitely deep tree where any single note can be cloned into multiple branches without duplication, building personal knowledge bases that mirror how ideas actually connect rather than forcing a single rigid folder hierarchy. Carrying forward the original Trilium project under active community stewardship with nearly 37,000 GitHub stars, the application is built on TypeScript with a CKEditor 5 WYSIWYG editor supporting rich text, tables, images, KaTeX math expressions, Mermaid diagrams, Excalidraw canvases, mind maps, spreadsheets with XLSX and CSV import/export, and code blocks with full syntax highlighting. A built-in JavaScript scripting engine runs on both frontend and backend, enabling custom widgets, automated workflows, scheduled tasks, and direct interaction with external REST services through a typed Script API. Full-text and fuzzy search with attribute-based queries locates any note instantly across databases tested at over 100,000 notes without performance degradation. The v0.104 release introduced importers for OneNote, Notion, Google Keep, Anytype, and Obsidian alongside 16 dedicated security fixes. Per-note AES encryption, OpenID Connect authentication, and TOTP two-factor protection safeguard sensitive content. The sync server keeps desktop clients, the progressive web app, and mobile devices in lockstep with zero third-party cloud dependency. Web Clipper captures content directly from browsers. 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.

Open the page, write a Markdown note, move on - Memos is a lightweight, self-hosted service built for quick capture. Instead of folders, notebooks, and titles, it presents a timeline: open the page, write a Markdown note, and move on. Notes support headings, code blocks with syntax highlighting, task lists, tables, and file attachments, with tags auto-extracted from #hashtags in the text. Each memo carries a visibility level, private, protected (logged-in users), or public, so one instance works as a personal log, a small team wiki, or a lightweight microblog. The backend is a single Go binary with a React frontend, around 50 MB of memory at runtime and a ~20 MB Docker image, so it fits comfortably on the smallest instance size with near-zero maintenance. SQLite is the default store, with MySQL and PostgreSQL supported for multi-user deployments needing more concurrency, and full REST and gRPC APIs - Connect RPC for browsers, gRPC-Gateway for external tools - make capture scriptable from CLIs, bots, and automation platforms. Fast full-text search spans all memos, pinned notes keep references handy, and a masonry view suits visual browsing. MIT-licensed with zero telemetry; content is stored as plain Markdown in a database you control, so notes remain readable, exportable, and free of proprietary formats.

A web interface for a folder of Markdown files - Flatnotes is exactly that, and the discipline of that design is why people love it. Every note is a plain .md file in a single flat directory: no database, no proprietary format, no hierarchy to maintain, no export step if you ever leave. Edit notes in the browser or open the same files in VS Code or Obsidian, sync them with Syncthing or rsync while the app is running - the Whoosh-powered search index synchronizes incrementally, so external edits just show up. The interface is a clean Vue.js app with both WYSIWYG and raw Markdown editing modes (TOAST UI Editor), instant full-text search behind the "/" shortcut with partial-match support, wikilinks for cross-note references, and automatic tag extraction from #hashtags in note bodies. Light and dark themes and a mobile-responsive layout make it pleasant everywhere. Authentication is flexible for a personal tool: none, read-only, username/password, or TOTP two-factor. A documented REST API covers create/read/update/delete for automation. The operational story is the quiet selling point - the only state is the notes folder and a rebuildable index, so backup is copying a directory. For a personal notepad that respects your data, Flatnotes nails minimal.

Poznote serves as an all-in-one personal knowledge base and digital workspace designed to bridge unstructured thinking and structured documentation. The platform pairs a responsive Markdown editor with live side-by-side rendering, KaTeX mathematical notation, and interactive Mermaid diagram compilation. Creative thinkers can switch instantly to an embedded Excalidraw infinite canvas to sketch system architectures, design mind maps, and create interface wireframes alongside their written notes. Every directory within the workspace can be toggled into an agile Kanban board where nested folders become customizable workflow columns and notes transform into draggable task cards. Task management views aggregate checklists across documents into unified priority queues with due date reminders and completion filters. An integrated bi-directional Git synchronization engine connects user workspaces directly to personal GitHub or Forgejo repositories, versioning edits automatically on save. The software also provides an integrated Model Context Protocol server that enables AI coding assistants to search notes, create documents, and query knowledge repositories securely. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Nowen Note is a self-hosted knowledge base where your notes, tasks, daily journals, and mind maps live in one private workspace you control. One tree holds folders, rich-text documents, and Markdown notes side by side, with drag-and-drop ordering, unlimited nesting, colored tags, pinning, and full-text search across everything. Each note can switch between a rich-text editor and Markdown with live preview, split view, outlines, tables, code blocks, math formulas, diagrams, comments, and version history. Connect the AI provider you prefer, such as an OpenAI-compatible API, Gemini, DeepSeek, or local Ollama, to continue drafts, rewrite passages, translate, summarize, and ask questions answered from your own notes. Tasks get list, board, calendar, and timeline views with dependencies, recurring rules, reminders, and templates, while daily journals capture short entries, moods, and photos and roll them into AI weekly and monthly reviews. Teammates edit together in real time, and folder-level permissions, passwords, allow and deny rules, share links with expiry dates, and guest comments decide exactly who sees what. Imports arrive from Obsidian, SiYuan, Word documents, web pages, and plain Markdown, attachments can live on local disk or S3-compatible storage, and scheduled backups travel to email or WebDAV. Keep working offline with a cached workspace that syncs when you reconnect, clip pages from the browser extension, and connect other tools through the OpenAPI, SDK, webhooks, and MCP server. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.

Real-time collaborative Markdown behind your own firewall: HedgeDoc (formerly CodiMD, descended from HackMD's open-source edition) keeps team notes on team infrastructure. Share a note's URL and collaborators are editing together instantly - live cursors, changes appearing keystroke by keystroke - in a three-mode interface that toggles between raw Markdown, rendered preview, and side-by-side split. The Markdown dialect is extended where engineers need it: Mermaid, Graphviz, and Vega-Lite diagrams, MathJax for equations, syntax-highlighted code blocks, embedded content, and a presentation mode that turns a note into reveal.js slides with a single YAML header. A dropdown permission system controls each note - freely editable, limited to signed-in users, or locked read-only - and published notes become clean read-only pages for wider distribution. Revisions track every change with the ability to revert to any earlier version. The AGPL-3.0 codebase is light enough to run on a Raspberry Pi and deploys via Docker with PostgreSQL, MySQL, or SQLite. Authentication covers LDAP, SAML, OAuth2, and email. It deliberately stays a focused document editor - no page trees or kanban - and does that one job with excellent keyboard-first ergonomics for meeting notes, RFCs, runbooks, and shared scratchpads.

With a deliberately minimalist design philosophy and zero database dependencies, DumbPad delivers a self-hosted notepad that stores notes as plain text files with real-time auto-saving every 10 seconds and keyboard-shortcut manual saves. The Node.js Express backend serves a vanilla JavaScript frontend that supports multiple named notepads with direct URL linking and shareable links for instant access to specific notes. The split-view editor displays markdown source on the left and rendered preview on the right with a draggable resize handle, while the full preview mode renders complete markdown with GitHub-style alert blocks for Note, Tip, Important, Warning, and Caution callouts, extended table formatting, fenced code blocks with syntax highlighting via highlight.js covering approximately 180 programming languages, collapsible details sections, and checklist support. Fuzzy search matches across both filenames and file contents for fast navigation across large collections. Optional PIN protection secures access with configurable 4 to 10 digit codes, constant-time comparison to prevent timing attacks, brute force lockout after 5 failed attempts with 15-minute cooldown, and IP-based tracking. The Docker container runs as non-root UID 1000 by default with multi-architecture support, CORS origin restrictions for reverse proxy deployments, and persistent data volumes. Notes can be downloaded as text or markdown files, printed with auto-expanded collapsible sections, and imported by placing text files directly into the data directory. On RepoCloud, deploy DumbPad on a dedicated VPS with Docker, root SSH access, and complete control over your note-taking infrastructure, all under the GPL-3.0 license.

No external database cluster to babysit, no proprietary cloud lock-in, and no bloated workspace hierarchy: Jotty stores every note, checklist, and Kanban board as plain Markdown and JSON files inside a single folder on your server. Need a quick grocery list with nested categories, progress bars, and drag-and-drop reordering? Spin one up in seconds, or flip any list into a multi-column Kanban project board with custom statuses, due-date calendar views, and a built-in time tracker. Write technical documentation in a TipTap-powered WYSIWYG and Markdown editor featuring syntax-highlighted code blocks, GitHub-flavored callouts, embedded Draw.io and Excalidraw diagrams, and OpenPGP client-side encryption for sensitive records. Connect ideas across your workspace using Obsidian-compatible wikilinks, inline mention suggestions, backlinks, and an interactive 2D and 3D knowledge graph that maps relationships between tasks and notes. Share individual notes or live Kanban boards publicly via customizable read-only links, or start the optional Model Context Protocol (MCP) companion container so AI assistants like Claude and Cursor can query your notes and check off items through your scoped REST API key. 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.

PenX delivers an open-source structured note-taking application that functions as a personal database disguised as an elegant editor — combining the outline workflow of Workflowy and Roam Research with the structured data capabilities of Tana through MetaTags that transform every note into a queryable database record. The local-first architecture stores all data on-device using PGLite, an in-process PostgreSQL-compatible engine, ensuring data ownership regardless of cloud connectivity. End-to-end encryption protects all synchronized data so that even the sync server cannot read your notes, tasks, ideas, or documents. GitHub-based version control provides out-of-the-box backup and history with full commit-level recovery. MetaTags are the core innovation — attaching structured tags to any note converts it into a database entry with typed fields, enabling table views, filters, and queries across your knowledge base without imposing rigid folder hierarchies. The daily notes workflow encourages free-form capture while MetaTags handle organization automatically, letting you record thoughts without deciding physical location upfront. AI-driven features assist with content generation, summarization, and intelligent search across your personal data hub. Real-time sync keeps web, desktop, and mobile in perfect alignment. Cross-platform availability includes web, desktop for Windows, macOS, and Linux, iOS, and Chrome extension. Deploy the web service via Next.js with pnpm using tRPC and Prisma. 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.

With over 75,000 GitHub stars and native apps across macOS, Windows, Linux, iOS, and Android, AppFlowy is the most widely adopted open-source alternative to Notion — delivering the same block-based workspace model with full data sovereignty. The Flutter frontend renders natively on every platform while a Rust backend powered by Actix-web and Tokio handles CRDT-based real-time collaboration, ensuring sub-second sync across devices with conflict-free concurrent editing. Relational databases support grid, board, kanban, calendar, and gallery views over the same dataset, with two-way relations, rollups, advanced filters, sorts, and formula calculations that cover the majority of Notion's database workflows. The block editor supports 40+ content types including nested pages, toggles, callouts, code blocks with syntax highlighting, embeds, and slash-command insertion. AI integration connects to OpenAI, Anthropic, or local models via Ollama for writing assistance, summarization, and translation — all without sending data off-premises when using on-prem LLMs. Team spaces with workspace-level and per-page permissions, OAuth and SSO authentication through GoTrue, and S3-compatible object storage via MinIO provide enterprise-grade access control and file management. The self-hosted stack deploys through Docker Compose with PostgreSQL for metadata, Redis for caching and pub/sub, and a dedicated background worker for imports and email notifications. Offline-first architecture ensures the desktop app functions without connectivity, syncing changes when the connection resumes. 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.

The entire wiki - content, code, and interface - is built from "tiddlers," small addressable units of information that link, transclude, tag, and filter into each other: TiddlyWiki is a non-linear personal notebook with a design philosophy unlike anything else in this catalog. Instead of pages in a hierarchy, you compose views by pulling tiddlers together on demand, which is why researchers, zettelkasten practitioners, and GTD devotees have sworn by it for two decades. The whole application is JavaScript, and the UI itself is written in hackable WikiText - customization goes as deep as rewriting the interface from inside the wiki. Self-hosting runs the Node.js version, which upgrades the classic single-HTML-file architecture in the ways that matter for a server: every tiddler is stored as an individual text file (Git-friendly, organizable), edits save through the HTTP API from any modern browser including phones, and one installation can serve multiple wikis blending shared and unique content. The plugin ecosystem covers graph visualizations, themes, languages, and hundreds of community extensions, declared per-wiki in a simple tiddlywiki.info file; the newer MultiWikiServer plugin adds multi-user accounts and tiddler sharing. Your notes stay usable for decades, independent of any corporation - the project's founding promise. BSD-licensed.