Open-Meteo
High-resolution weather forecasts became a free commodity because of Open-Meteo - and this deployment puts the whole open-source engine on your own infrastructure. The public open-meteo.com service aggregates national weather models (NOAA GFS, DWD ICON, ECMWF, Meteo-France, and others) into one consistent JSON interface; self-hosting gives you that same API without rate limits, third-party dependency, or usage metering. The architecture is two cooperating services: the API server exposes forecast endpoints fully compatible with Open-Meteo query parameters - latitude, longitude, hourly and daily variables like temperature, precipitation, wind, and radiation - while a background sync worker downloads fresh weather model data on a configurable interval into a shared persistent volume at /app/data, so forecasts stay current and survive restarts without re-downloading. You control which weather models to mirror, which variables to store, how much historical depth to keep, and how often to refresh - meaning a lean deployment can sync only the model and region you actually query. Responses are plain HTTP/JSON, so integration with dashboards, Home Assistant-style automations, agricultural monitoring, IoT fleets, or any application takes minutes. For anyone making thousands of forecast calls a day, replacing a metered weather API with your own instance turns a recurring bill into a flat infrastructure cost.
Monica
Take the tool sales teams use to never forget a client detail and point it at the people who actually matter - friends, family, the colleague whose kid's name you keep blanking on: Monica is a personal CRM. It's a Laravel/PHP application over MySQL where each contact accumulates the texture of a real relationship: how you met, family members and pets, work changes, addresses, notes from conversations, activities done together, gift ideas and gifts given, even debts owed in multiple currencies. Two features set it apart from every contact app. Reminders with staying power: set per-contact intervals (weekly through yearly), get notified at 30 days, 7 days, and day-of, with automatic birthday reminders and CalDAV sync to your calendar. And a journal linked to contacts: write about dinner with friends, tag each person, and build a timeline that's part diary, part relationship log - plus a daily "how was your day" rating. Monica is deliberately manual and deliberately private: no social network features, no AI, no email scraping, no ads, no analytics - a quiet database of what you know about people you love, on your own server. Multiple vaults and users, labels, custom activity types, and document/photo uploads round it out. AGPL-licensed.
OpenHAB
Over 400 technologies and thousands of smart devices from any manufacturer, unified under one roof: openHAB is the vendor-neutral home automation platform with a pluggable binding architecture. Each binding translates a device or service into openHAB's clean abstraction: Things expose Channels, Channels link to Items, and Items feed a rules engine that runs your home. That engine meets you at your skill level: Blockly gives non-programmers drag-and-drop visual logic, JS Scripting (GraalJS with the openhab-js library) is the modern text-based standard, the classic Rules DSL remains supported, and JSR223 opens the door to Python, Ruby, and Groovy. Time- and event-based triggers, scripts, notifications, and voice control compose into automations of any complexity, and users report decade-old rule sets still running rock solid. The Main UI handles configuration, semantic modeling, and now built-in charting - no external Grafana required. Built in Java on Apache Karaf's OSGi runtime and stewarded by the non-profit openHAB Foundation, it requires no cloud to function: everything runs locally, talking directly to your devices. Optional connectors bridge to Alexa, Google Assistant, and HomeKit, with iOS, Android, and web apps for control from anywhere.
Unleash
Deployment decoupled from release: Unleash, the most popular open-source feature management platform on GitHub, is a Node.js server backed by PostgreSQL. Ship code dark, then control who sees it through activation strategies: gradual percentage rollouts, targeting by user ID, IP, hostname, or application name, custom constraints against your own context fields, and scheduled or time-limited releases. Strategies stack - a flag activates if any strategy matches - and strategy variants layer A/B versions on top of the on/off decision. Each flag carries per-environment configurations, so a feature can run at 100% in staging while canarying at 5% in production. Backend SDKs (Node.js, Java, Go, Python, Ruby, .NET, PHP, Rust, and more) fetch configuration and evaluate flags locally, so a flag check adds zero network latency to request paths; frontend SDKs for React, Vue, Svelte, iOS, Android, and Flutter evaluate through a proxy layer. Flag hygiene is built in: flags are typed (release, experiment, operational, kill-switch, permission) with expected lifetimes, and Unleash marks overdue flags as potentially stale and surfaces unknown flags your SDKs request but that don't exist. Self-hosting via Docker keeps flag data, targeting rules, and evaluation infrastructure entirely on your side.
Supertokens Core
Authentication that lives inside your application rather than behind a redirect to an external identity provider - SuperTokens takes a fundamentally different architecture from Auth0 and AWS Cognito. Three tiers make that work - frontend SDKs (React, Angular, Vue, vanilla JS, React Native) render overridable login UI and manage tokens; backend SDKs (Node.js, Python, Go) expose auth endpoints on your own API domain; and SuperTokens Core, the piece you host here, is the stateless HTTP service handling core auth logic, password hashing, token signing, and database operations against PostgreSQL. The recipe system keeps features decoupled: use email/password, social login, passwordless (magic links, OTP), phone-password, multi-factor authentication (TOTP, WebAuthn), user roles, and microservice auth - individually or combined; you can even use SuperTokens purely for session management alongside another login provider. Sessions are where it shines: rotating refresh tokens with theft detection, automatic access-token refresh, CSRF protection, and secure cookie handling out of the box - the details that become vulnerabilities when hand-rolled. Verification happens locally in your backend via cached JWT signing keys, so the Core stays off the hot path. Self-hosted means no user limits, free forever, with all user data in your database. Apache-licensed.
Shaarli
Personal, minimalist, database-free bookmarking - Shaarli is a philosophy as much as an app. Everything lives in a single compressed datastore file inside data/: no MySQL, no PostgreSQL, backup by copying one directory. That write-once/read-many file is usually served straight from OS disk caches, which is why a decade-old Shaarli instance with tens of thousands of links still responds instantly. Designed deliberately single-user, it saves URL, title, unlimited-length description, and tags (with autocomplete, renaming, and merging), marks entries public or private, and automatically strips utm_source and fb tracking parameters from saved URLs. That description field is why the community uses Shaarli as far more than bookmarks: a microblog, read-it-later queue, code-snippet base, pastebin, and shared clipboard between machines. Sharing is one click via bookmarklet or Android apps; consumption is per-tag RSS/Atom feeds plus a daily digest feed; search is full-text with tag filtering. A REST API opens it to any client, a plugin and theme system extends the PHP core (Markdown rendering, thumbnails), and import/export uses browser-standard Netscape HTML - your data enters and leaves freely. LDAP login is supported, no telemetry is sent anywhere, and the UI degrades gracefully without JavaScript. The anti-cloud Delicious.
Wakapi
Its author, a student and WakaTime fan, didn't want to pay $9/month for data about his own keystrokes - so Wakapi was born, a self-hosted, WakaTime-compatible backend for coding statistics. The compatibility is the killer design decision: the official WakaTime plugins for VS Code, JetBrains IDEs, Vim, and dozens of other editors work unmodified - just point the plugin's API URL at your Wakapi instance with your personal key, and heartbeats flow to your server instead of a third party's. Duration inference matches WakaTime's own algorithm, with a configurable timeout (10 minutes by default). From that stream Wakapi builds statistics and plots across projects, languages, editors, hosts, and operating systems, plus the fun extras: public leaderboards (optionally login-gated, with configurable aggregation windows), badges for GitHub readmes, and weekly email reports. A REST API serves your data programmatically, Prometheus export feeds your existing Grafana, and a WakaTime relay mode can mirror heartbeats to both services during migration - with one-click import of historical WakaTime data. Written in Go, it is lightning fast and light enough for the smallest instance, storing to SQLite, PostgreSQL, or MySQL, with configurable data retention for GDPR peace of mind. Deliberately smaller than WakaTime, deliberately yours.
Isso
Named from the German "Ich schrei sonst" - roughly "or I'll scream" - Isso is a lightweight Python/JavaScript commenting server, a drop-in Disqus replacement for people who noticed what Disqus does to reader privacy and page load times. The design premise is printed right in the docs: comments are not Big Data. So the backend is a single SQLite file rather than a database cluster, and the entire client is one embeddable JavaScript file - 65 kB, 20 kB gzipped - that you drop into any static site, blog, or CMS. Commenters write in Markdown, need no account, and can edit or delete their own comments within a configurable window (15 minutes by default). Spam control comes from an optional moderation queue: held comments stay invisible until you activate them via an admin interface or email notification links. Migration is a first-class feature, with importers for Disqus and WordPress exports, so years of existing threads move over intact. Because everything is server-rendered from your own instance, no third party tracks your readers, and real-world switchers report smaller pages and faster loads than the Disqus embed. MIT-licensed, running since 2012.
PsiTransfer
Upload files, get a share link, let it expire: PsiTransfer is a self-hosted WeTransfer with no accounts, no logins, and no third-party cloud with size caps and metadata harvesting. The engineering focus is large files over imperfect networks. Uploads use the tus.io resumable protocol, so a dropped connection on a multi-gigabyte video resumes exactly where it stopped once you're back online; downloads support HTTP range headers for the same resilience, and everything streams, so file size is bounded by your disk rather than memory. Files organize into upload buckets with retention you control: expire after a set time (up to weeks) or after a one-time download, with automatic cleanup when links lapse. Recipients need nothing installed - they open the link, preview files in modal views, and grab everything as a zip or tar.gz archive with one click. Buckets can be password-protected (AES-encrypted download lists), and security-through-obscurity is done properly: bucket URLs use hashed UUID tokens and stored filenames are replaced with UUIDs. An optional admin page (enabled by setting an admin password) lists bucket information and storage. The Vue.js frontend ships under 100 KB gzipped and is fully responsive. Honest caveat from the author: no end-to-end payload encryption yet. BSD-licensed, Docker-ready.
Kan
What Trello fans wanted Trello to stay: Kan (kan.bn) is a minimalist, frills-free kanban board capturing the original vision before the enterprise pivots - and then adds the things 2025 actually demands. The core is exactly right: drag-and-drop cards across lists, labels and filters to find work fast, comments for discussion on cards, checklists, a detailed activity log tracking every change, and reusable board templates. Workspaces gather your team with member invites and role management, and board visibility controls decide who can view or edit each board. Migration is first-class: a built-in Trello importer brings existing boards over, so switching costs an afternoon, not a quarter. The standout differentiator is the bundled Model Context Protocol server exposing 46 tools across workspaces, boards, lists, cards, comments, checklists, labels, and members - meaning Claude Desktop, Cursor, Copilot, or any MCP client can read and manage your boards in natural language: "move everything assigned to me into Done" becomes a sentence, not a click marathon. The stack is modern TypeScript - Next.js, tRPC, Drizzle ORM over PostgreSQL, Better Auth (credentials or OAuth), Tailwind - with optional SMTP email and S3 file storage. Unlimited boards, lists, and cards; AGPL-licensed.
Node-RED
Wire nodes together in a browser, deploy in one click, and real-time data flows from sources through transformations to outputs: Node-RED is the OpenJS Foundation's flow-based programming tool for event-driven applications. Born at IBM as a proof-of-concept for manipulating MQTT topic mappings, it has become the lingua franca of IoT and automation glue - home automation, industrial control, edge data collection - with a community library of over 5,000 contributed nodes and flows covering protocols, devices, and services. Where visual wiring runs out, JavaScript function nodes written in a rich in-editor code editor take over, and every flow serializes to importable, exportable JSON that shares cleanly and version-controls sensibly. Version 5.0 (2026) delivered the largest editor overhaul in the project's history: a rethought layout with Explorer and Information panels in a split sidebar, a native dark theme with theme variants, improved accessibility, and refreshed node appearance. The runtime is lightweight Node.js, exploiting the event-driven non-blocking model so the same flows run on a Raspberry Pi at the network edge or a cloud VM. Apache-2.0 licensed with 240+ contributors, it pairs naturally with dashboard nodes for live charts and controls.
Chatpad
Why should your chat history live on someone else's servers? Chatpad AI - a React/TypeScript front end for the OpenAI API, built on the Mantine component library - is designed around that question. Enter your own OpenAI API key and start chatting with GPT models; every conversation, prompt, and setting is stored locally in your browser via DexieJS over IndexedDB, with no tracking, no cookies, and no backend database at all. That architecture is the point - the Docker image is just Nginx serving static files, making it one of the lightest AI deployments in the catalog, and pay-per-token API pricing typically undercuts a ChatGPT Plus subscription for moderate use. The interface earns its "premium quality" tagline with the details: a persona selector that switches communication styles per conversation, a saved-prompts library for messages you reuse constantly, organized chat history, and full data export/import so conversations move between browsers or into backups as files you control. A JSON config file customizes defaults - models, API endpoints, UI options - without rebuilding the image. AGPL-licensed, with desktop builds available upstream. For teams that want ChatGPT's utility with a self-hosted, zero-telemetry footprint, Chatpad is the minimal, sane answer.
drawDB
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.
Leantime
"As simple as Trello but as feature-rich as Jira" is how the Leantime team frames its goals-focused project management system for non-project managers - built from the ground up with ADHD, autism, and dyslexia in mind, with behavioral science shaping customizable dashboards, time blocking, low-cognitive-load prioritization, and Kanban, list, table, Gantt, and calendar views so each person works the way their brain does. The PHP application (AGPL, Laravel Blade frontend) connects strategy to execution: tasks with unlimited subtasks and dependencies roll up into milestones on a timeline, sprints and retrospectives handle iteration, and strategy-level blueprint boards - Lean Canvas, SWOT, risk analysis, goal and metric tracking - keep the "why" attached to the work. Knowledge lives alongside: wikis and docs, idea boards, comments on everything, file storage on S3 or local disk, even screen and webcam recording. Time tracking with timesheets supports estimation and client billing. Admin features are serious for an OSS tool: per-project permissions, two-factor auth, LDAP and OIDC single sign-on, Slack, Mattermost, and Discord integrations, a plugin system, and an expanding API that now powers a mobile app. Recent releases added multi-collaborator task assignment and low-vision accessibility improvements. Available in 20+ languages.
mCaptcha
The CAPTCHA bargain - annoy your users and feed their behavior to Google - gets replaced with economics by mCaptcha. Instead of image puzzles, it uses SHA256 proof-of-work: every visitor's browser silently solves a small computational challenge (via a WebAssembly library) before submitting a form. Humans never notice the milliseconds; bots hammering your site must burn more compute sending requests than your server spends answering them, which makes attacks more expensive than defense - the property that also makes mCaptcha genuine DoS protection, not just bot filtering. Written in Rust, the system is fully automated: difficulty scales with traffic, so challenges stay trivial in normal conditions and harden under attack. The privacy and accessibility wins are structural rather than promised: no tracking, no profiling, no user-pattern data collection, and no visual puzzles that exclude users with visual or cognitive impairments - the design was published in Communications of the ACM. Rate limiting is IP-independent, so users behind NATs, VPNs, or Tor get the same experience instead of endless challenge loops, and proofs resist replay attacks, neutering captcha farms. Migration is deliberately easy: the API is compatible with reCAPTCHA and hCaptcha, making it a drop-in replacement. AGPL-licensed core with proprietary-friendly client libraries.
Whoogle
Google's search results without Google's surveillance: Whoogle is a self-hosted proxy that strips the tracking and keeps the results. Your query goes from browser to your Whoogle instance, which fetches results from Google with a randomly generated User Agent and strips everything hostile before returning them: no ads or sponsored content, no third-party JavaScript or cookies, no AMP links, no URL tracking tags like utm_source, no referrer header - and Google sees your server's IP, never yours. Unlike metasearch engines that blend sources, Whoogle proxies Google exclusively, so result quality is exactly what you'd get logged out and incognito, minus the noise. A lightweight Flask app configured entirely through environment variables, it supports DuckDuckGo-style bang shortcuts, autocomplete suggestions, safe search, per-country and per-language filtering, site blocklists, and automatic rewriting of social links to privacy front-ends like Nitter and Invidious. Privacy hardening goes further: built-in Tor routing makes Google see an exit node instead of your server, HTTP/SOCKS proxy support covers other setups, and POST-based queries keep search terms out of logs. Light, dark, and fully custom CSS themes plus browser search-engine registration make it a drop-in default on desktop and mobile. Stateless, tiny, and trivial to run.
FireFlyIII
With over 24,000 GitHub stars and active development since 2014, Firefly III is the self-hosted personal finance manager that gives you complete control over your financial data without ever contacting external servers. The double-entry bookkeeping system tracks every transaction with source and destination accounts, ensuring accurate balance calculations and audit trails across checking, savings, credit card, cash, and asset accounts. Budget management sets monthly spending limits by category with visual progress tracking and rollover support for unused allocations. Rule-based transaction automation applies categorization, tags, and budget assignments automatically based on configurable conditions matching description, amount, source, and destination patterns. Recurring transactions schedule regular bills, subscriptions, and income entries with automatic creation on configured dates. Piggy banks divide savings accounts into virtual sub-accounts for goal tracking with target amounts and deadlines. Financial reports include income versus expense summaries, budget performance charts, category breakdowns, tag reports, and net worth tracking with weekly, monthly, and yearly time ranges. Multi-currency support handles any currency with configurable exchange rates for international finance tracking. The REST JSON API covers nearly every feature for integration with external tools, import utilities, and the companion Firefly III Data Importer for bank statement processing. Two-factor authentication provides account security. Self-hosting deploys via Docker containers or directly on PHP 8.5+ with MySQL or PostgreSQL. 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.
Dashy
Every service you run, behind one polished start page: Dashy is the most customizable homelab dashboard, built as a Vue.js homepage. Configuration lives in a single YAML file, but you never have to hand-edit it: an integrated UI editor with real-time validation writes changes back to disk, so both config-as-code and point-and-click camps are served. Status indicators put a live health dot next to every app - HTTP checks or pings on custom intervals, with response time and status details on hover - giving you an at-a-glance uptime overview before anything breaks. Over 50 built-in widgets pull dynamic content from the services you already run: Pi-hole and AdGuard block stats, Proxmox lists, Nextcloud status, Netdata CPU/memory history, Prometheus data, plus weather, RSS, crypto prices, and generic iframe/API-response widgets for anything with an endpoint. Instant fuzzy search launches any app as you type, with customizable hotkeys and web-search fallthrough. Theming is deep: dozens of built-in themes, a UI color palette editor, and custom CSS over CSS variables. Alternate views include a fast-loading minimal startpage and a workspace view that embeds apps side-by-side without leaving the dashboard. Icons resolve from Font Awesome, homelab icon packs, emojis, or auto-fetched favicons. Built-in authentication, multi-page support, cloud backup/sync, and multi-language round out an MIT project with a massive community.