250 Open Source Apps
Ranked & Scored

Self-hosted web app for common PDF operations (merge, split, compress, convert, OCR) exposed as a set of stateless HTTP endpoints. A strong open-source alternative to paid PDF tool suites.

The self-hosted cloud — files, calendar, contacts, and a 300+ app ecosystem on top of your own storage. The most mature, widely deployed alternative to Google Workspace/Dropbox.

A self-hosted URL shortener with a clean, API-first REST design. Standout trait is treating the API as the primary interface, with official web/CLI clients built on top.

A lightweight self-hosted note-taking service with a Notion/Twitter-hybrid feed UI. Standout trait is the single static Go binary with an embedded SQLite option, making it near-instant to stand up.

Lightweight, cross-platform web-based Postgres database browser distributed as a single Go binary. A read/write client tool rather than an application with its own data model.

An open-source feature flagging and A/B testing platform with a warehouse-native analytics model. Standout trait is edge-evaluated SDKs that keep flag checks fast and off the critical path of the app request.

A lightweight, config-as-code health-check and status-page tool. Standout trait is its fully declarative YAML config and single stateless binary design.

A modern, full-featured wiki platform with a polished editor, granular permissions, and pluggable authentication (local, OAuth, LDAP). Its standout trait is broad database portability — Postgres, MySQL, MariaDB, SQLite, or MSSQL.

Minimalist self-hosted bookmark manager with tagging, full-text search, and automatic snapshotting. Praised for its clean, no-nonsense Django architecture.

A modern, developer-friendly identity provider offering OIDC, social/enterprise SSO, MFA, and RBAC out of the box. Standout trait is a genuinely pleasant developer experience compared to older IdPs like Keycloak, without sacrificing backend-managed security.

A distributed tracing system for monitoring and troubleshooting microservice-based architectures. Standout trait is its pluggable storage backends (Cassandra, Elasticsearch, Kafka) built for large-scale trace ingestion.

A modern, actively-developed self-hosted alternative to Vercel/Heroku/Netlify for deploying apps, databases, and static sites via Docker/Traefik. Standout trait is its clean UI and fast-moving feature set compared to older PaaS tools like CapRover.

Self-hosted platform for provisioning remote developer workspaces on any infrastructure (Kubernetes, VMs, cloud) via Terraform templates, similar to GitHub Codespaces but infrastructure-agnostic.

Modern all-in-one mail server (SMTP, IMAP, JMAP) written in Rust as a single binary. Standout trait is consolidating what usually takes 5+ services (Postfix/Dovecot/Rspamd/etc.) into one memory-safe binary.

A mature, open-source feature-flag and experimentation platform with SDKs across most languages. Its standout trait is a clean, stateless-API architecture with strong RBAC and SSO support rivaling commercial LaunchDarkly-tier tools.

A self-hosted Google Photos replacement with mobile auto-backup and ML-powered face/object search. Standout trait is genuinely solid engineering across a real microservice architecture, at the cost of heavier ops.

Open-source feature flag and remote config management platform with SDKs for most major languages. Ships a full self-hosted stack (API, dashboard, Postgres) as an alternative to LaunchDarkly.

Open-source, self-hosted Git server with built-in CI pipelines, developed by Harness as a modern, lightweight alternative to GitLab.

Distributed task queue and durable workflow orchestration engine, positioned as a modern alternative to Celery/Temporal. Standout trait is a Postgres-backed, cloud-native design with strong developer ergonomics for defining workflows in code.

The industry-standard distributed event streaming platform for high-throughput pub/sub and log-based architectures. Standout trait is proven horizontal scalability to millions of messages/sec via partitioned, replicated topics.

A unified LLM gateway/proxy that exposes an OpenAI-compatible API in front of 100+ model providers, with virtual keys, budgets, and routing logic. Standout trait is its genuinely stateless proxy design, making it one of the more horizontally-scalable apps in this batch.

Payload is a code-first, headless CMS built on Node.js that generates a full admin UI and REST/GraphQL APIs from TypeScript schema definitions. Its standout trait is treating the CMS as a real application framework rather than a black-box product.

Prefect is a modern data workflow orchestration platform for scheduling and monitoring Python-based pipelines. Its standout trait is a hybrid execution model where the control plane never sees your data or code, only execution metadata.

Saleor is a headless, GraphQL-first e-commerce platform for building custom storefronts. Its standout trait is a fully API-driven architecture with no bundled frontend, giving complete control over the customer experience.

Excalidraw is a whiteboarding tool for sketching diagrams with a hand-drawn aesthetic, usable fully client-side or with live collaboration. Its standout trait is that the entire drawing engine runs in the browser, needing only a thin optional backend for real-time sync.

Real-time performance and health monitoring agent that installs per-node with near-zero configuration, exposing thousands of metrics out of the box with very low overhead.

A free, open-source media server for streaming your own movie/TV/music library with hardware-accelerated transcoding. Standout trait is a fully open alternative to Plex/Emby with no phone-home requirement.

A self-hosted live video streaming server with built-in chat and an elegant single-binary design. Standout trait is how much functionality (RTMP ingest, HLS output, chat, web UI) fits in one process.

oCIS (ownCloud Infinite Scale) is a ground-up microservices rewrite of ownCloud for file sync, share, and collaboration. Its standout trait is a cloud-native architecture with independently scalable Go services and pluggable storage/metadata backends.

A headless CMS/backend-as-a-service that wraps an existing SQL database with instant REST/GraphQL APIs and an admin UI. Standout trait is that it never owns a proprietary schema — the SQL database itself remains the source of truth.

Open-source headless CMS with a customizable admin panel and auto-generated REST/GraphQL APIs. Its plugin architecture and content-type builder make it a popular Contentful alternative for teams that want to self-host.

An end-to-end encrypted note-taking app with a self-hostable sync server, positioned as a privacy-first Evernote/Notion alternative. Its standout trait is a security-first design where the server only ever stores encrypted blobs, never plaintext.

Open-source Slack alternative with channels, threads, and enterprise SSO/compliance features. Solid Go architecture, though true high-availability clustering adds real operational complexity.

Apache Superset is a mature business intelligence platform for building dashboards and SQL-based data exploration. Its standout trait is broad database connector support and enterprise-grade row-level security under an established Apache project.

A privacy-focused, cookie-free web analytics platform positioned as a lightweight alternative to Google Analytics. Its standout trait is pairing Elixir/Phoenix's concurrency model with ClickHouse for extremely fast event aggregation at scale.

A modern, real-time forum platform with a plugin ecosystem and native mobile-friendly UI. Standout trait is websocket-driven live updates instead of full-page reloads for a forum-style app.

A lightweight self-hosted RSS/Atom aggregator with a fast, keyboard-friendly reading UI. Standout trait is its minimal footprint and support for multiple DB backends including plain SQLite.

SigNoz is an open-source observability platform unifying traces, metrics, and logs, positioned as a self-hosted Datadog alternative. Its standout trait is using ClickHouse as a single high-performance backend for all telemetry types.

A data orchestration platform for building, scheduling, and observing data pipelines with strong typing and asset-based lineage. Standout trait is its software-defined-assets model, which treats pipeline outputs as first-class, testable artifacts.

Zulip is a mature, open-source team chat platform with a distinctive topic-threaded conversation model. Its standout trait is deep threading that keeps large, high-volume teams organized better than flat channel-based chat.

A second-generation Matrix homeserver implementation in Go, designed as a lighter-weight, more horizontally scalable alternative to the reference Synapse implementation. Its standout trait is a component-based architecture that can run as a single monolith or split into independently-scalable microservices.

An Airtable-style spreadsheet-database UI that wraps an existing SQL database with auto-generated REST/GraphQL APIs. Standout trait is that it turns any Postgres/MySQL/SQLite schema into a no-code UI without owning the data model itself.

A PHP utility that generates RSS/Atom/JSON feeds for websites that don't natively offer one. Standout trait is near-zero configuration — a single stateless PHP container with dozens of site-specific scraper bridges built in.

Self-hosted alternative to Heroku/Vercel/Netlify for deploying apps, databases, and services from git. Standout trait is a clean Laravel-based control plane that manages Docker/Kubernetes targets declaratively.

A lightweight REST wrapper around the Apprise notification library, letting any app send a single POST to fan out notifications to 100+ services (Slack, email, SMS, push, etc). Its standout trait is a genuinely stateless, dead-simple architecture doing one job well.

An open-source LLM observability and evaluation platform for tracing prompts, costs, and quality metrics across LLM applications. Standout trait is its dual-database design combining Postgres for transactional data and ClickHouse for trace-scale analytics.

A minimalist, federated blogging platform speaking ActivityPub, so posts can be followed from Mastodon and the wider Fediverse. Its standout trait is a clean single Go binary that federates without the operational weight of larger Fediverse software.

A web UI for managing Docker and Kubernetes environments, containers, stacks, and images. Standout trait is broad multi-environment/agent support, offset by the security tradeoff of needing privileged Docker socket or K8s API access.

A single-binary home inventory and asset-tracking tool with a clean Vue frontend. Standout trait is its zero-dependency Go+embedded-SQLite deployment model.

A source-available workflow automation platform connecting hundreds of apps via a visual node-based editor. Standout trait is combining low-code workflow building with the ability to drop into raw JavaScript/Python nodes.

A self-hosted PaaS that wraps Docker Swarm behind a friendly CLI and dashboard so teams can push-to-deploy apps and one-click databases on their own VPS. Standout trait is how much Heroku-like ergonomics it squeezes out of plain Docker Swarm.

Fast self-hosted digital library server for comics, manga, and ebooks with reading progress tracking, OPDS support, and a modern reading UI.

A mature publishing/newsletter CMS with a headless content API and a polished Ember-based admin. Standout trait is its built-in email newsletter and membership/subscription engine.

Headless CMS and application framework generating a GraphQL API from a schema definition, backed by Prisma. Standout trait is a genuinely modern, type-safe developer experience compared to legacy PHP CMSes.

The free, open-source curriculum that's helped millions learn to code — full-stack web dev, DevOps, machine learning, and more, all self-paced and certificate-backed.

Local-first personal budgeting app (YNAB-style envelope budgeting) with an optional sync server for multi-device use. Data lives in a per-user SQLite file, keeping the architecture simple and privacy-friendly.

Open-source inventory management system for tracking parts, stock levels, and purchase orders, built on Django/DRF with a plugin architecture for extending workflows.

An open-source background jobs and workflow platform for developers, letting them write long-running, retryable tasks in TypeScript with full observability. Its standout trait is a modern developer experience rivaling hosted job-queue SaaS products.

Self-hosted team chat and omnichannel messaging platform comparable to Slack/Teams. Standout trait is deep protocol reach (matrix bridging, omnichannel, LiveChat) built on a mature Meteor/Node core.

An open-source project management tool positioned as a self-hostable alternative to Linear/Jira. Standout trait is its modern React frontend paired with a well-structured Django REST backend.

Open-source email alias service — every signup gets a unique forwarding address, so your real inbox never leaks. The self-hosted alternative to paying for email privacy.

An open-source BI tool that layers a semantic modeling layer and exploration UI directly on top of dbt projects. Standout trait is treating dbt models as the single source of truth for metrics, avoiding metric-definition drift.

Self-hosted uptime monitoring tool with a polished dashboard, 90+ notification integrations, and status pages. Runs as a single Node.js process backed by SQLite.

Personal knowledge base and note-taking app that stores everything as plain markdown files, with a client-side page indexer and plug-in scripting system. Runs as a single Deno process, making it exceptionally simple to self-host.

Self-hosted recipe manager and meal planner with a Vue frontend and recipe-scraping-from-URL feature. Clean, focused scope aimed at households rather than teams.

Minimal web-based file manager that exposes a directory over a browser UI with upload/download/edit. About as simple as self-hosted software gets, though it trades that simplicity for basic security features.

Self-hosted audiobook and podcast server with native mobile apps, library scanning, and playback progress sync across devices.

Full-featured helpdesk and ticketing system with multi-channel intake (email, chat, social, phone). Standout trait is its search-driven UI backed by Elasticsearch for fast full-text ticket search.

A spreadsheet-like UI for exploring and editing Postgres data directly, aimed at giving non-technical users safe, structured access to a real database. Standout trait is its deliberate single-database-dependency design — no separate app DB, just your Postgres.

A fast, YAML-configured personal dashboard for self-hosted services and homelab widgets, built on Next.js. Its standout trait is near-zero backend state — nearly everything lives in version-controllable config files.

A collection of handy client-side developer utilities (JSON formatter, JWT decoder, hash generators, etc.) bundled as a single web app. Nearly all logic runs in the browser, making the backend footprint minimal.

Spreadsheet-database hybrid (similar to Airtable) that combines familiar spreadsheet UX with a relational data model underneath. Each document is its own SQLite file with formula and API support.

Self-hosted privacy-respecting proxy front-end for Google Search that strips tracking, ads, and JavaScript. Essentially stateless, but operates in a legal/ToS gray area that public instances often run into.

The de facto standard for programmatic workflow orchestration, letting teams define DAGs of tasks in Python with rich scheduling, retries, and monitoring. Its standout trait is battle-tested maturity at genuine internet scale across thousands of production deployments.

An alert monitoring and deduplication API that ingests alerts from many monitoring tools and consolidates them into a single actionable view. Its standout trait is aggressive alert correlation/dedup logic that cuts through monitoring noise.

Open-source group scheduling and polling tool, similar to Doodle, for finding meeting times across participants. Modern Next.js stack with a straightforward Postgres backend.

Papermark is an open-source document sharing platform with link-level analytics, similar to DocSend. Its standout trait is a clean modern Next.js stack that's easy to self-host and extend.

The dominant open-source smart-home hub, integrating thousands of devices/services (Zigbee, Z-Wave, cloud APIs) behind a local-first automation engine. Its standout trait is an enormous, actively-maintained integration ecosystem combined with a strong local-control-first philosophy.

A self-hosted media server for comics, manga, and digital books with a polished reading web UI. Standout trait is its OPDS support for third-party reader apps.

Self-hosted bookmark and note-saving app (formerly Hoarder) with AI-powered auto-tagging, full-text search, and browser extensions for capturing content.

Self-hosted document management system that OCRs, tags, and archives scanned documents and PDFs. Pairs a mature Django backend with Postgres, Redis, Tika, and Gotenberg for format conversion.

Snipe-IT is an open-source IT asset management system for tracking hardware, licenses, and accessories across an organization. Its standout trait is a mature, feature-complete Laravel app purpose-built for IT asset lifecycles.

Real-time collaborative markdown editor for teams, a self-hosted alternative to HackMD, with live multi-cursor editing and slide/presentation export.

S.M.A.R.T. disk monitoring dashboard that tracks hard drive health and predicts failures across a fleet of machines. Standout trait is a clean, purpose-built single-binary design with minimal operational overhead.

Fast, simple photo gallery that indexes an existing photo library on disk rather than owning its own upload/storage model. Go backend with a GraphQL API keeps it lightweight compared to heavier media servers.

A flexible data labeling tool supporting text, image, audio, and video annotation for ML training data, with configurable labeling interfaces. Standout trait is its template-driven UI that adapts to nearly any annotation task without custom code.

PhotoPrism is an AI-powered self-hosted photo management app with facial recognition, object detection, and automatic tagging. Its standout trait is TensorFlow-based indexing running entirely on your own hardware.

Open-source kanban and project-board tool built by Mattermost as a Trello/Notion alternative, with a Go backend and Postgres or SQLite storage.

A self-hosted workout, nutrition, and fitness-tracking manager built on Django. Its standout trait is a mature Django REST API paired with a clean data model for exercises, routines, and body-metric tracking.

A headless, modular e-commerce backend (a Shopify alternative) exposing commerce logic — carts, orders, inventory, pricing — via API, with any storefront as the client. Its standout trait is a plugin/module architecture that makes deep commerce customization far easier than typical monolithic e-commerce platforms.

A polished team wiki/knowledge-base app with real-time collaborative editing. Standout trait is a Notion-quality editor experience, offset by a hard requirement on an external OIDC/SSO provider for auth.

Open-source API testing tool in the Postman mold, mostly client-side with an optional lightweight backend for synced collections. Very low operational overhead compared to most apps here.

Open-source design/prototyping tool positioned as a Figma alternative. Unusually solid engineering for this space, combining a Clojure backend with a TypeScript frontend.

A modern personal finance and wealth management app covering budgeting, net worth tracking, and investment monitoring, recently open-sourced with strong community momentum. Standout trait is a genuinely polished Rails/Hotwire UI compared to older finance tools.

Ansible Semaphore is a lightweight web UI for running and scheduling Ansible playbooks, Terraform, and other automation tasks. Its standout trait is a simple single-binary deployment that's far lighter than Red Hat's AWX/Tower.

Self-hosted cloud storage and file management platform supporting multiple storage backends (local disk, S3, OneDrive, and more), with a clean Google-Drive-like web UI.

Reference homeserver implementation for the Matrix decentralized chat protocol. Standout trait is first-class federation, letting independently-run servers interoperate in one chat network.

A lightweight, self-hosted Git service with a simple web UI, issues, and pull requests, distributed as a single Go binary. Standout trait is minimal resource footprint compared to GitLab, at the cost of slower feature development versus its Gitea/Forgejo forks.