Open Source Bulleted Outliners

AFFiNE is a collaborative knowledge base and productivity suite designed as a private-first, local-first platform. It provides an integrated workspace that combines structured documents with an infinite digital canvas, allowing users to organize complex information through a block-based model. By prioritizing local data persistence, the platform ensures immediate responsiveness and data sovereignty while maintaining a distributed state for real-time synchronization across multiple devices. The platform distinguishes itself through a canvas-integrated database engine that enables transitions between free-form whiteboarding and structured tabular views. It utilizes conflict-free replicated data types to manage concurrent edits, ensuring consistent collaboration. Users can extend the workspace with modular artificial intelligence integrations, which use natural language prompts to generate, summarize, and transform content into various visual or structured formats. The software is built for self-hosting, allowing teams to maintain full control over their data and infrastructure. It supports container-orchestrated deployment, providing tools for managing private workspaces, authentication, and production-ready environments. The system is designed to be installed and configured on personal or team-managed infrastructure, ensuring that all sensitive information remains within a private, secure, and scalable environment.

Notable is a local-first markdown note-taking application designed for managing personal knowledge bases. It functions as a document management system that stores all notes and attachments as plain text files directly on the local disk, ensuring data ownership and compatibility with external file-system tools. The application prioritizes a keyboard-centric workflow, utilizing a command-palette-driven interface to facilitate rapid navigation and content manipulation. It provides a distraction-free writing environment that allows users to hide interface elements, helping to maintain focus while composing structured documents. The platform supports advanced content management through hierarchical tagging, which allows for nested categorization of information. Users can perform batch operations on multiple items simultaneously, such as tagging or organizing large libraries, and utilize a side-by-side editor to view live previews of formatted markdown, including mathematical expressions, diagrams, and syntax-highlighted code blocks.

Zettlr is an academic markdown editor and research note management tool designed for professional writing and knowledge organization. It functions as a document processor that enables users to draft, structure, and manage research projects within a unified workspace. The application distinguishes itself by integrating a Zettelkasten-based knowledge management system, allowing users to link related research concepts and notes to foster discovery. It utilizes a local-file-system persistence model, ensuring that all data remains under user control and portable across different environments. The platform supports complex academic workflows by incorporating structured metadata and a modular conversion pipeline. This allows for the transformation of markdown files into various standardized publication formats, facilitating the preparation of documents for academic submission and professional publishing. The software is distributed as a cross-platform desktop application, providing a native interface for managing large collections of literature notes and source materials.

VNote is a native C++ desktop application designed as a Markdown note-taking platform and digital knowledge base. It provides a high-performance environment for organizing, editing, and structuring information using a Markdown-based content model. The application distinguishes itself with a Vi-style input mode for text navigation and a system of priority-based event hooks for extensibility. It further supports customization through CSS-based theme styling and global hotkey mapping. Broad capabilities include personal knowledge management via full-text and tag search, digital mind mapping, and integrated task lists. The system handles visual content through diagram and equation rendering and includes a PDF document viewer. Data persistence is managed through asynchronous saving and version history, while remote synchronization ensures notes remain consistent across different devices.

Blinko is a personal knowledge management system and an LLM-powered knowledge base that enables users to capture and organize thoughts through a bi-directional knowledge graph. It functions as a RAG-enabled note-taking application and a self-hosted Markdown editor, allowing for the creation of permanent documentation and fleeting notes. The project distinguishes itself by integrating retrieval-augmented generation to provide conversational querying and AI-powered analysis of private document libraries. It supports both cloud-based and local AI model integration, enabling users to perform semantic searches across multimodal content, including PDFs and images, while maintaining data privacy. The system covers a broad surface of capabilities, including hierarchical tagging, bidirectional linking, and a plugin-based extensibility framework with a dedicated marketplace. It manages data through a combination of hub-based and peer-to-peer synchronization, with support for S3-compatible object storage and automated archiving. The application is available for cross-platform deployment on macOS, Windows, Linux, and Android, and can be self-hosted using Docker containers.

Logseq is a privacy-focused, local-first knowledge base designed for personal information management and networked thought mapping. It functions as a bi-directional graph editor that organizes content into hierarchical, outliner-based structures, allowing users to connect related concepts through automated backlinking and visual relationship mapping. The platform distinguishes itself by maintaining all user data in plain text markdown files stored directly on the local device, ensuring offline availability and long-term portability. It employs a logic-based query engine to perform complex relational searches across the graph of notes and metadata, while a content-addressable storage model ensures data integrity for every information block. The application supports a broad range of information management tasks, including academic research synthesis and structured project documentation. Users can extend the core functionality through a sandboxed plugin system that allows for custom interface components and data manipulation. The software is documented through a dedicated resource library to assist with setup and configuration.

Trilium is a local-first personal knowledge management system designed to store and organize information on a user's own device. It functions as a hierarchical knowledge base where every note acts as both a standalone document and a container for nested children, allowing for complex information relationships and deep categorization. The platform distinguishes itself through a component-based interface that dynamically renders diverse content types, including rich text, diagrams, and executable scripts. All data is persisted within a single relational database file, which supports a versioned archive and a soft-delete lifecycle to protect information integrity. This architecture enables users to manage large volumes of interconnected data within a unified, extensible workspace. The system provides a comprehensive environment for digital asset organization, combining document management with scriptable automation. It utilizes a combination of server-side rendering and client-side orchestration to maintain a responsive interface for navigating and searching through structured information.

Habitica is an open-source productivity platform that applies role-playing game mechanics to personal task management. By tracking habits, daily goals, and to-do lists, the system translates completed tasks into character progression, experience points, and virtual rewards. The platform supports collaborative productivity by allowing users to join parties and complete group quests alongside their individual responsibilities. It is designed for self-hosting, providing users with full control over their data and system configuration through a structured relational database and a standardized application programming interface. The system includes built-in traffic management tools, such as request throttling and client identification, to maintain stability and monitor usage patterns. Developers can coordinate complex server and database components within local environments to facilitate testing and feature development.

Joplin is an open-source, cross-platform note-taking application designed for secure, private knowledge management. It functions as a local-first productivity platform, maintaining a complete relational database on the user's device to ensure offline availability and high-performance data retrieval. The application prioritizes data sovereignty by implementing an end-to-end encryption layer, which secures all information locally with a master key before any synchronization occurs. The platform distinguishes itself through a delta-based synchronization engine that transmits only specific file changes, optimizing performance across multiple devices and operating systems. Users can extend the core environment through a plugin-based architecture that supports custom themes, scripts, and UI components. For professional or collaborative environments, the software offers self-hosted synchronization options and team management capabilities, allowing organizations to maintain full control over their data infrastructure and security policies. Beyond core note-taking, the application supports rich multimedia content, including embedded files, diagrams, and mathematical expressions. It provides a comprehensive web-clipping tool for archiving online research and a RESTful API that enables programmatic access to notes and metadata for external integrations. The system is built on a cross-platform abstraction layer to ensure consistent behavior across desktop and mobile environments.

Marktext is a cross-platform desktop application designed for markdown document authoring and structured note-taking. It functions as a WYSIWYG text processor, providing a distraction-free interface that renders formatted content in real-time while hiding the underlying markup syntax. The application utilizes a multi-process architecture that separates system integration from the user interface, ensuring consistent performance across Windows, macOS, and Linux. By employing a custom editor core built on native browser capabilities and a structured syntax tree, it manages complex document elements such as mathematical expressions, diagrams, and code blocks. The software includes a plugin-based extension system that allows for the injection of custom functionality and interface components. It is distributed as an open-source project, maintaining a consistent environment for technical documentation and personal knowledge management.

Nyxt is a keyboard-driven web browser built on a programmable Common Lisp architecture. It is designed for users who require a highly extensible environment where core behaviors and internal functions can be modified during active sessions. By prioritizing keyboard navigation and a command-based interface, the browser facilitates efficient interaction with web content and system functions. The browser distinguishes itself through a non-linear, tree-structured history graph that preserves the context of navigation paths, allowing users to explore past visits without losing their current place. It utilizes a modular mode-based system that enables the dynamic injection of specific behaviors, security policies, and content-handling rules into isolated browsing buffers. This architecture is supported by a fuzzy-matching command interface that provides real-time filtering for rapid task execution and navigation. The platform includes comprehensive tools for managing large volumes of information, such as advanced tab management, metadata-rich bookmarking, and batch command execution. These features allow for the organization of browsing sessions through custom tags, complex search queries, and the ability to apply actions to multiple objects simultaneously. The system is distributed as a complete application with documentation available for users to configure and extend its functionality.

Taskbook is a command-line task manager and note-taking application that operates within a terminal interface. It functions as a CLI Kanban board, allowing users to organize work into boards with status tracking and priority levels, while persisting all data as structured JSON documents in a configurable local directory. The tool enables personal knowledge management by grouping tasks and plain text notes into named boards and sections to categorize different projects. It supports task prioritization, status tracking, and the ability to mark items as favorites for quick retrieval. The application includes capabilities for keyword search and attribute-based filtering, alongside visualization tools such as board overviews, progress summaries, and chronological timeline views. It also provides utilities for archiving deleted items and integrating selected content with the system clipboard. Application behavior and storage paths are managed via a JSON configuration file, command-line flags, or environment variables.