Automatisch
Automatisch runs your Zapier workflows on your own hardware - an open-source, self-hosted automation platform built as a direct alternative. Flows are chains of steps: one trigger (a polling or webhook event such as a new GitHub issue, a Stripe payment, or a form submission) followed by action steps that pass data downstream (post to Slack, append a Google Sheets row, update Notion). The visual builder deliberately mirrors Zapier's trigger-action model, so migrating existing Zaps requires no retraining and no programming knowledge. Roughly 60 integrations cover common business services - Slack, GitHub, Google Sheets, Notion, Stripe, Discord - and connections store credentials per service, with multiple accounts per app supported. Every execution runs on your own server: execution history, logs, and payload data never touch a third-party processor, which matters for GDPR, healthcare, and finance workloads. Error handling with retry logic, a REST API for programmatic flow management, and Docker Compose deployment round out the platform. The AGPL-3.0 Community Edition has no feature limits or per-task billing; an Enterprise Edition adds SSO, roles, and audit logs.
Scira
Scira is an AI search engine that breaks complex research questions into sub-tasks, retrieves grounded answers from live sources, and cites every claim with clickable links to the original evidence. Formerly known as MiniPerplx and now backed by nearly 12,000 GitHub stars, the platform implements agentic research planning where language models decompose queries, select appropriate tools, retrieve information in parallel, and synthesize responses with inline citations. Seventeen distinct search modes cover Web, Academic, Extreme, X (Twitter), Reddit, GitHub, Stocks, Crypto, YouTube, and Prediction markets, each activating a curated subset of the 28 built-in tools. The Extreme mode deploys a deep research agent with multi-step planning, parallel source retrieval, code execution in sandboxed Daytona environments, and R2 artifact storage for generated charts. Model routing spans 50+ AI providers through a unified configuration layer supporting OpenAI, Anthropic, Google, xAI Grok, and custom models, with per-mode model assignment based on task requirements. The web search tool supports Exa, Tavily, and Firecrawl as interchangeable providers via a Strategy pattern. Lookouts schedule recurring research agents on cron schedules that monitor topics, track changes, and email summaries using Upstash QStash for reliable execution. PostgreSQL stores chat history, user preferences, and custom instructions while Redis handles caching and rate limiting. 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.
Keeper
Work, personal, business, and school calendars at different providers double-book because no one system sees your real availability - Keeper solves that multi-calendar collision problem. Its pull-compare-push sync engine aggregates events from Google Calendar, Outlook/Office 365, iCloud, FastMail, any CalDAV server, or read-only iCal/ICS feeds, and pushes blocking events to one or many destination calendars so time slots align everywhere. The design is deliberately content-agnostic - it syncs timeslots, not titles or descriptions, so a personal appointment shows as busy time on your work calendar without leaking details. Sync logic is clean: events Keeper creates carry a traceable UID suffix, deletions propagate, and orphaned entries are purged automatically. A token-authenticated aggregated iCal feed combines selected calendars into one subscribable URL for Apple Calendar or Thunderbird. An optional MCP server gives AI agents read-only calendar access over OAuth 2.1 - list calendars and query events by date range, with no write capability. Built with Next.js and Bun under AGPL-3.0, the standalone Docker image bundles web, API, cron, worker, Redis, and PostgreSQL in one container, and self-hosting unlocks every Pro feature - unlimited calendars and one-minute sync intervals - for free.
Standard Notes
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.
Radicale
Calendars, to-do lists, journal entries, and contacts, synced over the open CalDAV and CardDAV standards nearly every client already speaks: Radicale is a small pure-Python server that works with Thunderbird, DAVx5 on Android, Apple Calendar and Contacts, GNOME, and many more. Its defining design choice is radical simplicity: there is no database. Events live as plain .ics files and contacts as .vcf files in an ordinary folder structure, which makes backup a copy command, migration a move, and disaster recovery a matter of reading text files. The server works out of the box with no complicated setup, then grows as needed: flexible authentication (htpasswd files among other methods), per-collection authorization rules, TLS-secured connections, and a plugin system for extending storage, auth, and rights handling. Built-in limits on parallel connections, file sizes, and failed authentication attempts harden it for network exposure behind a reverse proxy. A bundled web interface handles creating and managing calendars and address books - useful since many clients cannot create collections themselves. Maintained since 2011 with 140+ contributors, GPLv3-licensed, and light enough to run on the smallest VPS or a Raspberry Pi.
Budibase
Step right up to the magical world of Budibase, the open-source wizardry that turns the grueling task of building internal tools into a walk in the digital park. Imagine crafting mighty tools and formidable forms in less time than it takes to brew a cup of coffee, all without typing a single line of code! With Budibase, you can charm data from an ancient external database, summon information from a Rest API, conjure up figures from a CSV, or create something entirely new with Budibase's own mystical database. Design your digital dominion with a flick of the drag-and-drop, and automate your kingdom's workflows as if by magic. Join the ranks of the 75,000 teams who've harnessed the power of Budibase to accelerate their business quests. Need to safeguard data like a digital fortress, automate tasks like a sorcerer, or streamline operations like a high-speed chariot? Budibase is your trusty steed in the race to operational victory. And with RepoCloud hosting, you'll save a treasure chest of gold compared to those other cloud-dwelling giants!
Roundcube
Two decades of continuous development made Roundcube the standard-bearer of open-source webmail - a PHP IMAP client that gives any mail server a polished, application-like interface in the browser. It connects to whatever IMAP/SMTP stack you run - Dovecot, Postfix, a hosted mailbox - and delivers the full desktop-client experience: drag-and-drop message management, threaded conversation views, full MIME and HTML mail handling, find-as-you-type address book with groups and LDAP connectors, multiple sender identities, full-text search, and spell checking in dozens of languages. The default Elastic skin is genuinely responsive, working as well on a phone as a desktop, and the entire UI is skinnable. The plugin API is where deployments get shaped: managesieve exposes server-side filter management in the UI, enigma brings PGP encryption and signing via GnuPG, markasjunk trains spam filters, zipdownload batches attachments, password lets users change credentials, and attachment_reminder catches the classic forgotten-attachment email - among hundreds of community plugins. Built-in caching keeps large mailboxes fast, IMAP ACLs and shared folders support team setups, and XSS protection is engineered into the rendering pipeline. It scales from a single personal mailbox to unlimited users, backed by MySQL, MariaDB, PostgreSQL, or SQLite. GPL-licensed with regular security releases.
ScribeWizard
Audio lectures become structured, Markdown-formatted notes in about a minute with ScribeWizard (also known as GroqNotes). Upload an MP3, WAV, or M4A file - or paste a YouTube link - and the app runs a three-stage pipeline on Groq's LPU inference hardware: Whisper Large v3 transcribes the audio, a larger Llama model drafts a comprehensive outline of the material, and a faster Llama model fills each section with detailed content. This scaffolded prompting strategy is the core idea: the strong model handles structure where quality matters most, the fast model handles volume, and Groq's 1200+ tokens-per-second inference keeps the whole process near real time. Output renders as clean Markdown with support for tables and code blocks, and finished notes download as text or PDF. Model selection is configurable - swap in other Groq-hosted open models like Mixtral or Gemma to trade speed against quality or work around rate limits. Built as a single Streamlit app by Benjamin Klieger at Groq, it needs only a Groq API key to run, making it one of the simplest self-hosted AI tools to operate.
Cozy Cloud
With over 1,200 GitHub stars, 12,000+ commits, and more than a decade of active development distributed under the AGPL-3.0 license, Cozy Cloud operates as a comprehensive personal data hub that goes far beyond file storage by connecting your documents, contacts, calendars, banking transactions, energy bills, and productivity tools into a single self-hosted platform where no third party profiles you. The cozy-stack Go binary handles file storage, CouchDB document management, job scheduling, app serving, and the REST API in a single process consuming approximately 150MB of RAM idle. Sandboxed konnectors import data from 50+ external services — banks, utility providers, telecom operators, cloud drives — running as isolated jobs via nsjail to prevent untrusted code from accessing other user data. The built-in app store serves web applications in subdomain-isolated environments with Content Security Policy headers, each app communicating exclusively through the documented REST API. Real-time synchronization via PouchDB replication and WebSocket keeps files, contacts, and documents consistent across desktop clients, mobile apps for iOS and Android with automatic photo backup, and the web interface. Security features include automatic Let's Encrypt TLS certificates, Argon2id password hashing, optional TOTP two-factor authentication, and GDPR-compliant data export via the CLI. Each user receives their own isolated instance with independent storage, database, and application configuration. 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.
Siftly
Siftly transforms your Twitter/X bookmarks from a chaotic pile of saved tweets into a searchable, AI-categorized knowledge base with an interactive visual mindmap. With over 2,700 GitHub stars since March 2026, the platform runs a four-stage enrichment pipeline on each bookmark: entity extraction mines hashtags, URLs, @mentions, and 100+ known tool domains without API calls; vision analysis generates 30-40 visual tags per image using the Anthropic SDK; semantic tagging produces 25-35 searchable descriptors; and categorization assigns one to three categories with confidence scores. Search combines SQLite FTS5 full-text indexing with Claude-based semantic reranking, narrowing candidates through keyword matching, category-intent detection, and deduplication before sending a bounded set for LLM relevance scoring, letting you find bookmarks by meaning rather than exact keywords. The interactive mindmap built on @xyflow/react renders your entire collection as a force-directed graph organized by category with expandable nodes, color-coded legends, and direct links to original tweets. Import bookmarks through a built-in bookmarklet or console script without browser extensions, then browse in grid or list view with filters for category, media type, and date range. Export as CSV, JSON, or category-grouped ZIP archives. Prisma 7 manages the local SQLite database with FTS5 built in, requiring zero external database setup. A bundled CLI provides JSON-output commands for stats, search, and category management. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.
EasyAppointments
Service businesses get a booking page without per-booking commissions or monthly SaaS fees from Easy!Appointments, the self-hosted appointment scheduler. Customers pick a service, provider, and open time slot from a clean web form; the system enforces working plans, breaks, and booking rules you define per provider, then confirms by email to both sides. The structure fits real service organizations: multiple providers with individual schedules, multiple service types with their own durations and prices, and admin/secretary roles for front-desk management. Two-way Google Calendar synchronization keeps each provider's external calendar authoritative - book in Easy!Appointments and it appears in Google Calendar, block time in Google and the slot disappears from the booking form. Version 1.6 adds SMS notifications and payment support, and a REST API opens the scheduling data to custom integrations. Built on PHP (CodeIgniter) with MySQL, it installs in a single folder and can share a database with your existing site; a WordPress plugin embeds the booking form directly in pages or posts. The interface ships in dozens of languages with time-zone handling throughout. GPL-3.0 licensed and free for commercial use - a helpdesk, clinic, salon, or consultancy runs its whole booking workflow on its own server.
Tandoor
The deep end of self-hosted recipe management: Tandoor Recipes is a Django/Vue application that replaces Paprika, AnyList, and ad-choked recipe sites with a database you control. Import is where most people start: paste any URL and Tandoor scrapes schema.org markup for ingredients, instructions, images, times, and nutrition; bulk-paste URLs for batch import; or migrate wholesale from Mealie, Paprika, Nextcloud Cookbook, Pepperplate, and other managers with built-in importers. The structured recipe editor tracks ingredients individually, which is what powers everything downstream: full-text search with trigram similarity, a "what can I make with what's in the fridge" ingredient search, automatic nutrition via OpenFoodFacts, and shopping lists that merge duplicate ingredients across recipes, convert units, scale by servings, and sort by your supermarket's actual aisle layout. The weekly meal planner is drag-and-drop, feeds shopping lists automatically, exports to your calendar, and shows a nutritional summary for the week. Multi-user support comes with a granular permission system - shared household cookbooks, private recipes, even secret ones - and shopping lists sync in real time so two people can shop simultaneously. A full REST API integrates with Home Assistant and Grocy. For households serious about cooking, Tandoor's depth is unmatched.
Atomic
Atomic transforms collections of personal Markdown notes into an AI-augmented knowledge graph by breaking documents down into semantically linked conceptual units. Users capture thoughts, research excerpts, and web clippings as modular notes that the system automatically chunks, embeds, and categorizes with hierarchical tags. An interactive force-directed canvas maps out the entire knowledge base, positioning related ideas closer together based on embedding cosine similarity rather than manual folder hierarchies. Built-in vector search queries across text embeddings directly within SQLite, retrieving precise contextual snippets in response to natural language prompts. The automated wiki engine synthesizes disparate notes into comprehensive reference articles equipped with verifiable inline citations back to original source materials. Integrated conversational agents leverage retrieved knowledge context to answer research questions, surface contradictions across past entries, and draft structured daily briefings. External AI tools can read, search, and update stored knowledge through an embedded Model Context Protocol server endpoint. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.
Glean
Information overload is the default state of the modern internet, and Glean exists to tame it by pulling every blog, newsletter, and news source you follow into a single, organized reading experience with an interface that prioritizes clarity over clutter. Subscribe to RSS and Atom feeds, import your existing subscriptions via OPML, and organize everything into multi-level folders with a flexible tagging system that lets you slice your reading list by topic, priority, or mood. A three-pane layout presents your feed list, article summaries, and full content side by side, with one-click actions for marking articles as read, saving them for later, bookmarking favorites, or archiving what you have already processed. Background workers fetch new articles every 15 minutes so your feeds stay current without manual refreshes. The preference learning engine (backed by Milvus vector embeddings) scores incoming articles against your reading history and surfaces a personalized Smart Feed of content you are most likely to care about, reducing the time spent scrolling past irrelevant posts. A built-in MCP server lets AI assistants like Claude Desktop search and interact with your feed library directly. The admin dashboard on a separate port provides user management, system monitoring, and configuration controls for multi-user deployments. Bookmark external URLs from any browser with the Chrome extension, or access your feeds on mobile through the Progressive Web App. 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.
Kurrier
Kurrier unifies email, calendars, contacts, and file storage in a single web interface that connects to any email provider you already use. The Next.js frontend with Nitro API worker deploys via Docker Compose on PostgreSQL and Redis, delivering a cohesive workspace where IMAP/SMTP mailboxes from Gmail, Outlook, or corporate servers sit alongside transactional providers like AWS SES, SendGrid, Mailgun, and Postmark. Automatic inbox building handles threads, attachments, sent items, and deletion sync through persistent background polling. The CalDAV backend enables full two-way calendar synchronization with iOS, macOS, Android via DAVx5, and Thunderbird, supporting event invitations, RSVP processing through the inbox, timezone-aware scheduling, and contact-aware attendee linking. CardDAV contacts sync bidirectionally across all devices with unified name, avatar, and email resolution. Kurrier Drive provides integrated file storage through WebDAV locally or S3-compatible backends for cloud storage. Multiple identities and domains let you manage several email accounts from different providers in one interface, with fast local search indexing subjects, senders, and content without dependency on external APIs. The API-first architecture exposes clean endpoints for automation and custom integrations. 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.
Tymeslot
Built on Elixir's fault-tolerant OTP runtime, Tymeslot delivers the complete scheduling toolkit that Calendly charges for and Cal.com relicensed away from open source in 2026. Share one booking link and let clients pick available slots — your calendar stays synchronized and double-bookings disappear automatically through real-time availability checking against Google Calendar, Microsoft Outlook, and any CalDAV server including Nextcloud. Meeting types support configurable durations, buffer times, and availability windows that clients can book without email back-and-forth. Phoenix LiveView powers the real-time UI with WebSocket connections that update instantly as bookings arrive, without client-side JavaScript framework overhead. The platform attaches Zoom video rooms to confirmed bookings through your own Marketplace app credentials, sends confirmation and reminder emails via SMTP, Postmark, SendGrid, Mailgun, or AhaSend, and supports custom booking page themes with embed options for integration into existing websites. Circuit breakers, connection pooling, and graceful degradation maintain availability during provider outages. Authentication supports local accounts, GitHub OAuth, and reCAPTCHA protection on public booking forms. Self-hosting deploys as a single container with PostgreSQL embedded — no separate database container required. Two named volumes persist uploads and database state, while the same image powers the managed cloud at tymeslot.app so self-hosted users get identical features without a crippled community edition. Deploy via Docker, Cloudron with automatic updates, or Railway from a community template. 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.
APITable
With over 15,000 GitHub stars and positioning itself as the most feature-complete open-source alternative to Airtable, APITable combines a buttery-smooth spreadsheet interface with a full database engine and automatic API generation that turns every datasheet into a queryable REST endpoint without writing a single line of backend code. Real-time collaborative editing powered by Operational Transformation algorithms supports 100,000+ rows with multiple simultaneous users, while seven built-in view types — Grid, Kanban, Gallery, Gantt chart, Calendar, Mindmap, and Form — let teams visualize the same data in whatever format suits their workflow. The one-click API panel exposes every table as a documented REST API with filtering, sorting, and pagination, effectively functioning as a backend-as-a-service for frontend developers and automation builders. Robot automation triggers workflows on record changes with integrations into n8n, Zapier, Appsmith, and Slack, while the extensible widget system provides 20+ open-source widgets for custom charts, dashboards, and data visualizations embedded directly into datasheets. Enterprise features include SAML single sign-on, field-level and row-level permissions via Mirrors, organizational team management, audit logging, database auto-backup, and data export. Bi-directional table linking with infinite cross-links creates relational data models across workspaces, and built-in templates cover CRM, project management, inventory, and content planning. 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.
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.