Backed by Y Combinator and trusted by over 2,300 companies processing billions of observations monthly, Langfuse is the most widely adopted open-source platform for building, monitoring, evaluating, and debugging LLM applications. The hierarchical tracing engine captures every LLM call, tool invocation, retrieval step, and agent action as nested spans based on OpenTelemetry, with automatic cost calculation, latency tracking, and token usage attribution across sessions and users. Prompt Management separates prompts from code with versioned artifacts, label-based deployments, one-click rollbacks, and runtime SDK fetching with server-side caching, while linking every generation back to its exact prompt version for attribution analytics. The evaluation system supports LLM-as-a-judge scoring, heuristic code evaluators, user feedback collection, and manual annotation workflows that run automatically on production traces or against curated datasets. The Playground enables interactive prompt testing on real production inputs with side-by-side model comparison across providers. Datasets and Experiments define test cases for systematic benchmarking with comparative result visualization. Native SDKs for Python and TypeScript provide decorator-based instrumentation, while 100+ integrations cover LangChain, LlamaIndex, OpenAI SDK, LiteLLM, Vercel AI SDK, and any OpenTelemetry-instrumented framework. The analytics dashboard surfaces cost breakdowns, quality scores, latency percentiles, and usage trends across models and prompt versions. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Quote to cash in one web application - create quotes, convert them to invoices, record payments, track customers: iDURAR is an open-source ERP and CRM platform for small and medium-sized businesses. Built on the MERN stack (MongoDB, Express, React, Node.js) with Ant Design components and Redux state management, it presents a clean SaaS-style interface that needs little onboarding. Core modules cover invoice management with PDF generation and email delivery, payment recording against invoices, quote and proforma handling, customer records, and accounting views over the resulting data. Multi-currency support and localization make it usable for internationally operating teams. Because the whole stack is JavaScript with an API-first backend, extending it - custom fields, new modules, integrations - is approachable for any Node/React developer rather than requiring a specialist ERP skill set. Deployment is straightforward via Docker with a MongoDB instance. Licensed under AGPL-3.0 with free commercial use; a hosted enterprise version exists but the self-hosted edition is fully functional.

With over 9,100 GitHub stars and production deployments powering real-time analytics at companies like SHOPLINE where it reduced API latency by 76.7%, RisingWave is the PostgreSQL-compatible streaming database that collapses the traditional Debezium-plus-Kafka-plus-Flink-plus-serving-database stack into a single Rust-powered system. The platform continuously ingests data from PostgreSQL and MySQL via native CDC connectors that eliminate Debezium middleware, consumes Kafka, Redpanda, Pulsar, and Kinesis topics, accepts webhook events from SaaS applications, and batch-loads historical data from S3 and data warehouses. Standard SQL defines sources, materialized views, and sinks — no new DSL, no Java, and no custom API — while the PostgreSQL wire protocol means psql, DBeaver, pgAdmin, Grafana, Metabase, Superset, Tableau, and every PostgreSQL client library works without modification. Materialized views are incrementally maintained as events arrive, delivering point lookups in single-digit milliseconds without recomputing aggregates from scratch. For long-term retention, RisingWave writes to Apache Iceberg tables with a hosted REST catalog and automated table maintenance including compaction, small-file optimization, and snapshot cleanup, with data queryable by Spark, Trino, DuckDB, and DataFusion. The disaggregated compute-storage architecture uses S3-based state management for elastic scaling, instant failure recovery measured in seconds rather than the minutes-to-hours typical of RocksDB-based systems, and cost-efficient storage tiering. An MCP server enables AI agents to query and operate RisingWave directly. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

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.

With over 52,000 GitHub stars and its role as the foundation of every Kubernetes cluster worldwide, etcd is the distributed key-value store that handles the most critical data in modern infrastructure — cluster state, configuration, service discovery, and distributed coordination. Built in Go and graduated from the CNCF, etcd uses the Raft consensus algorithm to maintain a strongly-consistent, highly-available replicated log across a cluster of machines, gracefully handling leader elections during network partitions and tolerating machine failure including the leader node. The gRPC API provides atomic key-value operations including put, get, delete, and transactions with multi-key compare-and-swap semantics, enabling distributed locking, leader election, and configuration management without external coordination. Watch operations stream real-time change notifications for specific keys or key ranges, powering reactive architectures that respond immediately to configuration updates. Version 3.7 introduces RangeStream for streaming large result sets in chunks, keys-only range requests for faster metadata queries, and bootstraps entirely from v3store after eliminating the legacy v2 store dependency. Automatic TLS encryption with optional client certificate authentication secures all cluster communication, while role-based access control restricts key access per user. The embedded bbolt B+ tree storage engine provides consistent reads and writes with configurable compaction policies. Benchmarked at 10,000 writes per second per instance with linearizable reads, etcd supports clusters of 3, 5, or 7 members for fault tolerance. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

Reaching 24,000 GitHub stars within two years of its first commit in July 2024, Beszel delivers Netdata-grade monitoring dashboards from a single Docker container with no Prometheus stack, no external database, and no complex configuration — just a one-binary hub on PocketBase (SQLite embedded) and a sub-15 MB agent per host that auto-discovers Docker and Podman containers on contact. The agent connects outbound via WebSocket or SSH tunnel, requiring zero open ports on monitored servers and zero manual network configuration. Per-host metrics cover CPU usage, memory with swap and ZFS ARC breakdown, disk I/O across multiple partitions, network throughput, load average, sensor temperatures, battery charge, and GPU utilization with power draw for Nvidia, AMD, and Intel cards — features that competitors lock behind paid tiers. S.M.A.R.T. disk health including eMMC wear indicators and Linux mdraid array status surface hardware degradation before failures occur. Container statistics track CPU, memory, and network history per container with automatic discovery as new containers start. Configurable threshold alerts notify via email, Discord, Telegram, ntfy, Pushover, Gotify, Matrix, Mattermost, Signal, Slack, Microsoft Teams, and Twilio when metrics exceed defined limits. Multi-user accounts with OAuth/OIDC authentication let teams share monitored systems with role-based access, while automatic backups persist data to disk or S3-compatible storage. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Contracts signed on your own server: DocuSeal is the most feature-complete open-source, self-hosted alternative to DocuSign. A WYSIWYG builder turns any PDF into a fillable form with 14 field types: signature, initials, date, file upload, checkbox, dropdown, radio, stamp, and more. Documents route to multiple submitters in sequence or parallel, with automated SMTP email notifications, reminders, and a mobile-optimized signing experience that works on any device without an account. Every completed document carries an automatic PDF eSignature with verification and an audit trail. Templates are reusable and can also be generated programmatically - from HTML via API or from PDFs and DOCX files with embedded field tags - and the REST API plus webhooks drive full workflow automation, with embedded signing forms and form builders for React, Vue, Angular, and plain JavaScript. Files store on disk or in S3, Google Cloud Storage, or Azure. The UI ships in 7 languages with signing in 14. Runs on SQLite, PostgreSQL, or MySQL; AGPL-3.0 licensed with unlimited documents and no per-signature fees.

With 27,000 GitHub stars and 349 releases shipping multiple times per week, Huly replaces four separate SaaS subscriptions — Linear for issue tracking, Notion for documents, Slack for team chat, and Motion for time-blocking — with a single self-hosted platform that charges nothing per seat. The issue tracker provides projects, sprints, roadmaps, custom workflows, and Kanban views with bi-directional GitHub and GitLab synchronization that keeps issues and pull requests in lockstep across both systems. Collaborative documents use CRDT-based real-time editing for wikis, meeting notes, and technical specs with nested page hierarchies and rich embedding. Team messaging delivers channels, direct messages, threaded conversations, reactions, and pinned messages in a Slack-equivalent interface that lives alongside your project context. The time-blocking planner schedules tasks into calendar slots with drag-and-drop, integrating directly with your issue backlog so nothing falls through cracks. A virtual office module provides audio and video rooms for standups and pair programming with external guest access. HR features handle team management, office hours, and PTO tracking. The architecture runs 30+ microservices on CockroachDB for ACID-compliant storage, Elasticsearch for full-text search, MinIO for file attachments, and Redpanda for event streaming. Desktop apps ship for macOS, Windows, and Linux alongside mobile apps for iOS and Android. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. EPL-2.0 licensed.

Halo is a modern CMS that handles blogs, knowledge bases, corporate sites, and full e-commerce storefronts from a single installation, distinguished by a polyglot plugin architecture that runs both Java and JavaScript extensions on a GraalVM runtime. Built on Spring Boot 3 with a Vue.js admin console, the platform delivers a clean content management experience with Markdown and rich-text editing, live preview, scheduled publishing, draft management, media uploads, and granular multi-user role-based access controls. Plugins can be enabled or disabled at runtime without restarting the server, and the official marketplace offers over 100 free themes plus a growing library of extensions covering SEO optimization, search integration, paid content access, AI writing assistance, and Q&A chatbots. Storage backends are configurable through plugins, supporting local disk, S3-compatible object storage, and other providers. The fully documented RESTful API enables headless CMS usage for decoupled frontend architectures. Database support includes embedded H2 for quick starts, with production deployments on PostgreSQL or MySQL. Nearly 40,000 GitHub stars and over 2.5 million Docker pulls reflect the project's maturity and active development pace. A single Docker command gets a functional instance running on port 8090. 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.

Processing over one billion tasks per month on Hatchet Cloud and holding 7,600+ GitHub stars, Hatchet is the open-source orchestration engine that replaces fragile legacy queues with durable, fault-tolerant task execution built entirely on PostgreSQL — no Redis, RabbitMQ, or Kafka required. Born from the creators' experience scaling Uber's Cadence-inspired patterns, the v1 engine achieves 10,000 tasks per second sustained throughput with 20ms average queue latency through dynamic buffer flushing and batch insert optimization. Define tasks, durable workflows, and DAG pipelines as code using native SDKs for Python, TypeScript, Go, and Ruby — every function gets automatic retries with configurable backoff, concurrency control with group round robin or cancellation policies, priority queuing, and dynamic rate limiting for third-party API protection. Durable execution persists the complete history of every task and state transition, enabling replay from failure, debugging via full event timelines, and complex pause/resume conditions using durable sleep and event waits. The real-time web dashboard provides workflow run visualization with DAG timeline rendering, worker health monitoring with slot utilization, queue depth metrics, task throughput charts, and error rate tracking — all filterable by status, workflow, or time window. OpenTelemetry integration and Prometheus metrics export enable advanced observability. Multi-tenant by default with users, roles, and namespace isolation. Self-host via Docker Compose with PostgreSQL and optional RabbitMQ, or use the single-container Hatchet Lite image for development. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Confluence and Notion both want your team's documentation in their cloud; Docmost, an open-source collaborative wiki platform, keeps it on your server. The centerpiece is a Notion-style block editor with CRDT-based real-time collaboration: multiple people edit the same page simultaneously and changes merge without conflicts or overwrites. Content lives in spaces - per team, project, or department - with nested page trees, role-based permissions, groups, inline comments, page history with restore, and full-text search across everything. The editor covers tables, code blocks, callouts, KaTeX math, and file attachments, and diagramming is built in rather than bolted on: Mermaid, Draw.io, and Excalidraw all render inside pages, alongside embeds for Airtable, Loom, Miro, and more. Migration paths include Notion, Markdown, HTML, and ZIP archive imports (Confluence, PDF, and DOCX importers ship in the Enterprise edition, along with SSO via SAML/OIDC/LDAP and MFA). The stack is TypeScript with PostgreSQL and Redis, deploys via Docker Compose, runs in air-gapped environments with no external dependencies, and is translated into 10+ languages. The AGPL-3.0 community edition carries no per-seat fees; the project has passed 20,000 GitHub stars since its 2024 launch.

Cognee gives AI agents persistent long-term memory that survives across sessions, replacing the traditional stack of separate graph, vector, and session databases with a unified engine running on a single PostgreSQL instance. The memory-native API exposes four verbs (remember, recall, forget, and improve) enabling agents to persist context, retrieve cited answers, prune outdated knowledge, and self-improve from feedback. Under the hood, Cognee combines pgvector embeddings with a PostgreSQL-native graph store and cognitive-science-grounded ontology generation, delivering hybrid retrieval that fuses semantic similarity, structural graph traversal, and lexical search in a single query. Integrations span Claude Code, Cursor, LangGraph, OpenAI Agents, and any MCP-compatible client through a dedicated MCP server on port 8001, while the Python and TypeScript SDKs provide direct programmatic access. The platform supports swappable backends including Neo4j, FalkorDB, Qdrant, ChromaDB, Weaviate, Milvus, and LanceDB for teams with existing infrastructure. Built-in OpenTelemetry tracing, an experimental dashboard with knowledge graph visualization, multi-tenant user isolation, and audit trails ensure production readiness. Deploy via Docker Compose with optional profiles for PostgreSQL, Neo4j, Redis, and the web frontend. Reached v1.0 in April 2026 with 30,000+ stars. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

CRMs, project trackers, inventory tools - NocoBase is an open-source no-code/low-code platform for building business systems like these. Its architecture is data-model driven: you define collections and relationships first, then compose any number of interface blocks (tables, forms, kanban, charts) on top of the same model, so data structure is never coupled to a particular view. The core is a microkernel where every feature is a plugin, WordPress-style; you enable official plugins, install marketplace ones, or write your own as npm packages with server and client parts. Data sources include the main PostgreSQL or MySQL database, external databases, and third-party APIs - so you can build admin panels over existing production data instead of migrating it. Built-in infrastructure covers role-based permissions down to collection, record, and field level, workflow automation with approval steps and scheduled triggers, and audit logs; a one-click switch flips between usage and configuration modes. Because custom features live in isolated plugins with a documented lifecycle, core upgrades do not overwrite your customizations, and swapping UIs never requires data migrations since interfaces sit on independent models. Written in TypeScript on Node.js, Koa, and React under the AGPL license, it is light enough for one person to run and extend - and where no-code SaaS platforms charge per seat and per app, a self-hosted instance runs unlimited applications for unlimited users at hosting cost alone.

With 11,400+ GitHub stars and active development since 2019, Gatus is the developer-oriented status page and health monitoring tool that ships as a single statically-linked Go binary in a scratch Docker image under 20 MB — deploying in seconds while monitoring your entire infrastructure across 12 protocols from a single YAML configuration file. Define health checks for HTTP, ICMP, TCP, DNS, gRPC, WebSocket, SSH, UDP, SCTP, STARTTLS, and TLS endpoints with conditions that go far beyond simple ping: evaluate response status codes, body content with JSONPath expressions, response time thresholds, certificate expiration days, DNS record values, and IP address ranges. Each endpoint supports independent alerting through Slack, Microsoft Teams, PagerDuty, Discord, Telegram, Twilio, Mattermost, Google Chat, email, Gotify, Pushover, and custom webhook providers with configurable failure thresholds and descriptions. The built-in status page displays uptime badges, response time graphs, and incident timelines with maintenance window support for planned downtime communication. External endpoints accept push-based health reports from services behind firewalls. Prometheus metrics export via the /metrics endpoint enables integration with existing observability stacks. OIDC and Basic Authentication protect the dashboard. PostgreSQL persistence stores historical uptime data. The official Helm chart supports Kubernetes deployment with liveness probes and PVC storage, while a community sidecar auto-generates endpoint configurations from Kubernetes Ingress and HTTPRoute resources. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

Grocy is a household management system, bringing ERP-grade inventory tracking to kitchens, pantries, and homes worldwide. The stock management system tracks products with expiration dates, best-before dates, and opened tracking, while barcode scanning via USB readers or device cameras with Open Food Facts product lookup enables rapid item entry. Minimum stock amounts trigger automatic shopping list entries so frequently used products never run out, and multiple shopping lists can be maintained and shared across household members. Recipe management links ingredients directly to stock inventory, showing at-a-glance fulfillment status and a Due Score that highlights recipes best suited for consuming items approaching expiration. The meal planner organizes daily meals across customizable time periods and adds all missing ingredients to shopping lists with one click. Chore tracking schedules recurring household tasks with assignment to specific members, due date tracking, and completion history logging. Battery management monitors charge cycles for household devices with configurable reminder intervals. Custom fields and userfields extend any entity with additional data, while feature flags disable unused modules to simplify the interface. The RESTful API with integrated Swagger UI at the /api endpoint exposes every operation the web frontend uses, enabling third-party integrations with home automation systems. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

With over 43,000 GitHub stars and adoption by companies including Nasdaq, Samsung, and Expedia, Kong Gateway is the world's most deployed open-source API gateway, processing billions of API requests daily across hybrid-cloud and multi-cloud architectures. Built on the battle-tested NGINX engine with OpenResty's LuaJIT runtime, Kong delivers sub-millisecond proxy latency while supporting REST, gRPC, GraphQL, WebSocket, SOAP, and Kafka protocols. The plugin architecture includes authentication via JWT, Basic Auth, HMAC, key authentication, OAuth 2.0, and LDAP, alongside rate limiting with configurable windows per consumer, IP address, or API key. The AI Proxy plugin provides a universal LLM API that routes across OpenAI, Anthropic, Google Gemini, AWS Bedrock, Azure AI, Databricks, Mistral, and Hugging Face through a single standardized interface, while MCP proxy capabilities convert REST APIs into MCP tools and provide traffic governance for AI agents. Kong supports declarative configuration via YAML for GitOps workflows, a RESTful Admin API for dynamic configuration, and decK CLI for version-controlled infrastructure-as-code management. Upstream health checking with active and passive probes enables automatic failover, and the ring balancer distributes traffic across upstream targets with consistent hashing, round-robin, or least-connections algorithms. The Kong Plugin Hub hosts over 100 community and official plugins covering logging, monitoring, transformation, security, and traffic control. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

Arcane gives you a single polished dashboard to manage Docker containers, images, volumes, networks, and Compose projects across unlimited remote hosts. The SvelteKit frontend paired with a Go backend delivers real-time resource monitoring with historical graphs, container lifecycle controls including shell exec and live log streaming, and one-click Docker Compose deployment with Git repository synchronization for version-controlled stack definitions. The manager-agent architecture connects remote environments via Direct TCP on port 3553 or Edge mode where agents initiate outbound gRPC/WebSocket connections through NAT and firewalls without requiring inbound ports, all secured with mTLS certificates. Vulnerability scanning identifies security issues in running container images directly from the interface. The backup system enables scheduled container snapshots with configurable retention for disaster recovery. Network and volume administration includes visual relationship mapping between services, and the responsive interface supports dark/light themes with full mobile optimization and community-driven internationalization via Crowdin. 6,500+ stars and 89 releases since April 2025 reflect a rapid development cadence. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. BSD-3-Clause licensed.

With over 77,000 GitHub stars, Crawl4AI is the most-starred open-source web crawler on GitHub and the go-to tool for converting the web into AI-ready data. Built on Python and Playwright, it transforms any website into clean Markdown with headings, tables, code blocks, and citation hints optimized for LLM ingestion, or extracts structured JSON via CSS selectors, XPath expressions, or direct LLM-based schema extraction through OpenAI, Anthropic, and Ollama providers. The self-hosted Docker server exposes a REST API on port 11235 with endpoints for crawling, streaming results, screenshots, PDF generation, JavaScript execution, and LLM-powered extraction. Version 0.9.x introduced secure-by-default operation with mandatory JWT authentication, strict request validation, declarative hooks replacing inline code, and bounded job queues. Adaptive crawling uses information foraging algorithms to determine when sufficient data has been gathered, while deep crawl mode traverses link graphs intelligently. The async browser pool manages concurrent sessions with stealth plugins, proxy rotation, custom headers, and session persistence for authenticated scraping. A built-in MCP server enables direct integration with Claude, ChatGPT, and Cursor for AI-driven web research workflows. Content filtering applies BM25 and TF-IDF relevance scoring to extract only pertinent sections from noisy pages. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.