Real-time alerts from your own infrastructure to your phone, with no Firebase, Pushover, or third-party push service in the path: Gotify is a simple, self-hosted notification server written in Go. The model is deliberately minimal: senders push messages with a single HTTP POST to the REST API, receivers subscribe over a WebSocket stream, and a clean React web UI manages the pieces. Senders are namespaced as "applications," each with its own token, so your backup script, Uptime Kuma, CI pipeline, and cron jobs each get an identity, an icon, and independently revocable credentials - centralized alerting from many services with per-source management. Messages carry a title, body, and priority level that maps to notification importance on the client. The official Android app (on both F-Droid and Google Play, notable for working entirely without Google Play Services) shows push notifications for new messages; the web UI itself supports Web Push in the browser; and gotify/cli pushes messages from shell scripts with one command. A server-side plugin system adds custom behavior, and the whole thing runs as a single small binary with SQLite by default - near-zero resource footprint. Because dozens of tools (and Apprise) speak Gotify natively, it slots in as the notification hub for an entire homelab or ops stack.

SnappyMail is a fast, privacy-respecting webmail client that connects to any existing IMAP and SMTP server, booting in under a second with a JavaScript payload of just 138 KB under Brotli compression (down from RainLoop's 8 MB fork origin). No database is required: all configuration and user data persists as flat files in a single volume, making Docker deployment trivially simple with the roughly 30 MB image consuming approximately 50 MB of RAM. Built-in PGP encryption supports three backends: OpenPGP.js v5 with ECDSA and EDDSA key generation, GnuPG integration, and Mailvelope browser extension compatibility, eliminating the need for separate encryption plugins. The integrated Sieve script editor enables users to create mail filtering rules, vacation auto-responders, and forwarding conditions directly within the web interface when connected to ManageSieve-capable servers on port 4190. Multi-domain administration allows a single instance to serve users across multiple IMAP servers with per-domain authentication routing. The admin panel manages extensions, security settings, branding customization, and domain configuration. GDPR-friendly by design, it removes all social media integrations, Gravatar lookups, and external tracking present in RainLoop. Dark mode strips background and font colors from email messages. The modified Squire HTML editor replaces CKEditor for composing rich-text messages. Scores 99% on Lighthouse performance. 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.

A Node.js server, a large shared canvas, and a URL - WBO (Whiteboard Ophir) is collaborative whiteboarding reduced to its essence. There are no accounts and no setup - to collaborate, you send someone the board's link, and every stroke appears for all connected users in real time over WebSockets, with cursor positions shared so you can see where collaborators are working. Board state persists automatically and continuously, so a diagram drawn in today's lesson is still there next week at the same URL. Boards come in three flavors: a public free-for-all, private boards with random unguessable names, and named boards with custom URLs shared by anyone who knows the name. The tools cover teaching and brainstorming needs - pencil, straight lines, rectangles, ellipses, text annotations, eraser, a full color palette with brush sizes - and boards export as SVG or PNG. Despite the simplicity, the server is production-minded: JWT authentication gates board access with granular capabilities (open, edit, and clear as separate permissions), rate limiting caps per-client message volume, reverse-proxy and subpath deployment are supported, and OpenTelemetry provides metrics, logs, and traces. It works on tablets and touch devices, speaks multiple languages, and consumes minimal resources. AGPL-licensed.

Websurfx aggregates results from multiple search engines into one private, ad-free interface that never tracks your queries. Written in Rust, the backend provides memory safety against buffer overflows and data races at the language level while handling concurrent requests across upstream providers like DuckDuckGo and Searx. A built-in re-ranking algorithm scores and merges results by relevance, producing a unified page that draws from many sources while appearing as one coherent search. Safe-search filtering operates across four levels from unrestricted to complete content blocking, with regex-based filter lists for parental controls in schools and organizations. Upstream requests route through configurable proxy chains or Tor, preventing search providers from correlating your queries with a specific IP address. Four Docker image variants target different caching strategies: hybrid Redis plus in-memory for maximum throughput, Redis-only, in-memory-only, or zero-persistence for environments where cached queries must never touch disk. The Lua configuration file controls engine selection, request timeouts, rate limiting thresholds, and production-mode delays that throttle upstream traffic to prevent abuse. Quick-result widgets handle calculations, currency conversions, and unit transformations inline without external redirects. Image search capabilities serve visual discovery for designers and researchers who need media results without surveillance. Runs on a RepoCloud VPS with dedicated resources and full root access. AGPL-3.0 licensed.

Unlimited agents, unlimited tickets, unlimited mailboxes, forever, on a $4 VPS - FreeScout's pricing inversion is why it became the most popular self-hosted Help Scout alternative, a PHP/Laravel help desk and shared inbox developed from scratch over eight years. The inbox deliberately behaves like Gmail or Outlook, so new support agents need close to zero training. The email-support core is genuinely complete: seamless IMAP/SMTP integration including modern Microsoft Exchange authentication, collision detection that warns when two agents open the same conversation, canned responses, auto-replies, internal notes, open tracking, starring, forwarding, merging, and moving conversations between mailboxes, phone-call logging, push notifications, and an auto-refreshing conversation list - plus screenshot pasting straight from the clipboard into replies. It's 100% mobile-friendly, fully screen-reader accessible, and translated into 28 languages. Beyond the core, an ecosystem of 100+ modules (mostly one-time $12-20 purchases) adds knowledge base, workflows with Gmail-filter-style automation rules, satisfaction ratings, time tracking, tags, custom fields, LDAP, Slack, WhatsApp and Telegram channels, and an API with webhooks - pay only for what your team needs. Web installer and updater included. AGPL-licensed.

SpiderFoot is an open-source OSINT automation platform, replacing hours of manual reconnaissance with automated intelligence gathering across more than 200 data collection modules. The platform accepts ten distinct target types including IP addresses, domains, hostnames, network subnets, ASNs, email addresses, phone numbers, usernames, person names, and Bitcoin addresses, then feeds them through a publisher-subscriber event bus where each module's findings trigger downstream analysis automatically. SpiderFoot queries Shodan, VirusTotal, HaveIBeenPwned, AlienVault OTX, Censys, crt.sh, WHOIS databases, social media platforms, breach databases, and dozens more sources, with most modules requiring no API keys and many offering free tiers for those that do. The YAML-configurable correlation engine applies 37 pre-defined rules to identify relationships between discovered data points, flagging patterns like shared infrastructure, credential exposure, and domain reputation anomalies. Results export in CSV, JSON, and GEXF graph formats for integration with external analysis tools. TOR integration enables dark web searching, and SpiderFoot can invoke external tools including DNSTwist, Whatweb, Nmap, and CMSeeK for deeper technical assessment. The embedded web server delivers an intuitive dashboard for scan management, data visualization, and result exploration alongside a full command-line interface for scripted automation. 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 31,600 GitHub stars and thousands of production deployments, InfluxDB 3 Core is the open-source time series database rebuilt in Rust on the FDAP stack — Apache Flight for high-throughput data transfer, DataFusion for vectorized SQL query execution, Arrow for columnar in-memory representation, and Parquet for compressed columnar storage. The engine delivers sub-10ms query response times on recent data and handles millions of writes per second through line protocol ingestion over HTTP, with unlimited tag cardinality eliminating the high-cardinality limitations that plagued earlier InfluxDB versions. The diskless architecture persists data as compressed Parquet files to S3-compatible object storage, Azure Blob, Google Cloud Storage, or local disk with configurable partitioning strategies, while the write-ahead log and in-memory buffer serve real-time queries against recent data before compaction. Native SQL support through DataFusion includes window functions, CTEs, subqueries, and joins, while InfluxQL maintains backward compatibility with existing InfluxDB 1.x and 2.x applications through the same query API. The embedded Python VM enables processing engine plugins and triggers that execute custom logic on write events, perform cross-database queries, and transform data in real time without external tooling. Flight SQL clients provide high-performance query access from Python, Go, Java, and Rust, and the HTTP API supports writes in line protocol format compatible with Telegraf's 300+ input plugins. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT/Apache 2.0 dual-licensed.

Among open-source Mailchimp alternatives, Keila has the most modern UI - built in Germany on Elixir and Phoenix (the PETAL stack), with GDPR-conscious defaults including an optional no-tracking mode, and 100% open source with no proprietary premium tier. Campaign authoring is flexible three ways: a visual block editor with multi-column layouts, Markdown with or without WYSIWYG for hybrid HTML-plus-plain- text sends, and raw MJML for hand-coded designs. The personalization system is unusually clean - every contact carries custom data as a single JSON object (populated from sign-up form fields or pushed from your CMS/CRM), and Shopify's Liquid template language renders it into fully dynamic emails. Targeting uses a visual segment editor backed by a powerful segment language for complex logic over tags, language preferences, and any custom field. Sign-up forms with custom fields grow your lists; open and click tracking measures campaigns; scheduled sending handles timing. Delivery pipes through your own SMTP or first-class integrations with AWS SES (including automated bounce handling), SendGrid, Mailgun, and Postmark. A full REST API manages contacts, campaigns, and segments, with Erlang/OTP reliability underneath. Comfortable at 100K+ subscribers. AGPL-licensed, EU-hosted project, actively developed.

Monitoring everything from network switches to Kubernetes clusters since 2001 with over 6,200 GitHub stars and deployments exceeding 100,000 devices per installation, Zabbix has established itself as one of the most mature and feature-rich open-source monitoring platforms available, trusted by organizations including Dell, Salesforce, ICANN, and T-Mobile. The platform collects metrics from virtually any source using Zabbix Agent written in C, Zabbix Agent 2 written in Go with native plugin support, SNMP v1/v2c/v3 polling and trapping, IPMI for hardware health, JMX for Java applications, SSH and Telnet checks, HTTP/HTTPS polling, and ODBC database queries. Version 7.0 LTS introduced synthetic browser monitoring that executes user-defined JavaScript via WebDriver to simulate multi-step user interactions on websites, proxy load balancing with automatic host redistribution across proxy groups for high availability, in-memory proxy data buffering delivering up to 100x performance improvement, native multi-factor authentication with TOTP and Duo support, and just-in-time user provisioning from SAML and LDAP. Low-level discovery automatically detects file systems, network interfaces, SNMP OIDs, VMware resources, and Kubernetes pods, creating monitoring items and triggers dynamically. The alerting engine correlates events with configurable escalation chains, sending notifications through Slack, Microsoft Teams, PagerDuty, Jira, email, and SMS with customizable message templates. Over 1,000 official templates provide instant monitoring for Linux, Windows, VMware, AWS, Azure, Docker, PostgreSQL, MySQL, Apache, Nginx, and hundreds more. 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.

OpenSEO provides an alternative to the $100+/month SEO suite monopoly by connecting directly to DataForSEO APIs on a pay-as-you-go basis — you bring your own API key and pay only for the queries you actually make. The platform delivers focused workflows for keyword research with volume, difficulty, CPC, intent, and live SERP inspection; rank tracking with historical position monitoring; backlink analysis with referring domain quality scoring; technical site audits that crawl pages and surface issues; competitor insights comparing SERP positions across keyword sets; and AI visibility monitoring that tracks brand mentions, citations, and prompts across AI models. The integrated MCP server exposes all tools to AI coding agents including Claude Code, OpenClaw, Hermes, and Cursor, while Agent Skills provide reusable SKILL.md workflows that guide agents through complex SEO research tasks. Google Search Console integration reads first-party performance data including clicks, impressions, CTR, and position metrics with URL-level index status inspection. The Prompt Explorer compares how different AI models respond to SEO-relevant queries. Self-host via Docker for personal use or deploy to Cloudflare for team access with automatic database backups. The hosted version at openseo.so adds a 28% markup on DataForSEO requests. 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 28,600 GitHub stars and 450 contributors, Grafana Loki is the log aggregation system that takes the Prometheus approach to logging — indexing only metadata labels instead of full log content, making it dramatically cheaper and simpler to operate than traditional log management platforms. The label-based indexing strategy groups log streams using the same labels already applied to Prometheus metrics, enabling seamless switching between metrics and logs in Grafana dashboards without maintaining separate indexing infrastructure. Grafana Alloy, the telemetry collector replacing Promtail, scrapes and pushes logs with Prometheus-style service discovery, automatic Kubernetes Pod label extraction, and pipeline stages for parsing, filtering, and relabeling before ingestion. LogQL, the query language, combines label matchers for stream selection with regex line filters and aggregation functions, supporting rate calculations, pattern parsing, and metric generation from log data for alerting and dashboard panels. The storage architecture writes compressed log chunks and TSDB indexes to S3, GCS, Azure Blob Storage, or MinIO-compatible object stores, with configurable retention and compaction policies. Deployment modes scale from a single binary for development through monolithic high-availability mode with multiple replicas to full microservices decomposition with separate ingester, distributor, querier, query-frontend, compactor, and ruler components on Kubernetes via Helm charts. Multi-tenancy isolates data and query paths per tenant through header-based tenant ID assignment. 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.

With over 11,500 GitHub stars, 20 contributors, and nine releases through version 1.4.0 in May 2026, Aureus ERP has established itself as the modern Laravel-powered alternative to legacy ERP systems like Odoo and ERPNext by packaging accounting, inventory, manufacturing, HR, sales, procurement, and project management into a modular MIT-licensed platform where you install only the plugins your business actually needs. Built on Laravel 13 with FilamentPHP 5 admin panels and TailwindCSS, each module installs via a single Artisan command that automatically resolves dependencies, runs migrations, seeds default data, and generates role-based permissions through Filament Shield integration. The Accounts module defines chart of accounts, journals, ledgers, currencies, and fiscal structures while the Accounting module handles journal entries, financial reports, period closing, and reconciliation workflows. Inventory management provides warehouse operations with stock tracking, transfers, and adjustments while Manufacturing handles bills of materials, manufacturing orders, work orders, and work center scheduling. The Sales module manages pipeline stages and opportunity tracking while Purchases handles procurement workflows and vendor management. HR capabilities span employee management, recruitment with applicant tracking, leave management through Timeoffs, and employee hour tracking via Timesheets. The Projects module provides planning and task management with the Maintenance module covering preventive and corrective equipment maintenance with calendar views. Docker deployment pulls a single image bundling PHP, MySQL, Apache, and Node.js for immediate browser access. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

OpenSearch is a search and analytics platforms, powering full-text search, log analytics, observability, and AI-powered vector retrieval at petabyte scale. The distributed engine provides BM25 full-text search alongside k-NN vector search using NMSLIB, Faiss, and Lucene libraries, enabling semantic search, hybrid search combining keyword and vector scoring through normalization processors, neural sparse search, and retrieval-augmented generation workflows with built-in ML Commons for model hosting. OpenSearch Dashboards delivers interactive visualization with Discover for log exploration, custom dashboards, alerting, anomaly detection using Random Cut Forest algorithms, and Security Analytics with detection rules mapped to MITRE ATT&CK. Native Prometheus integration with full PromQL support unifies metrics alongside logs and traces in a single observability interface, while Data Prepper handles telemetry ingestion from OpenTelemetry collectors, Fluent Bit, and Logstash-compatible pipelines. SQL and Piped Processing Language queries with a visual PPL builder enable analysts to query data without learning the native DSL. Index State Management automates index lifecycle with rollover, shrink, and delete policies, while cross-cluster replication and searchable snapshots on S3-compatible storage provide disaster recovery. Scoped API keys, field-level security, document-level security, and audit logging deliver enterprise-grade access control. Docker Compose deploys multi-node clusters alongside the Kubernetes operator for orchestrated production environments. 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.

OpenFGA answers the question 'can this user perform this action on this resource?' in single-digit milliseconds, implementing Google's Zanzibar paper as a production-ready authorization engine adopted by Auth0, Grafana Labs, Canonical, Docker, Agicap, and Read.AI. The server exposes both gRPC and HTTP APIs for authorization queries including Check, ListObjects, ListUsers, Expand, and the high-throughput BatchCheck endpoint that deduplicates and processes multiple authorization decisions in a single request. Authorization models combine relationship-based access control with role-based and attribute-based patterns through a purpose-built DSL that supports contextual tuples, conditional relationship tuples with CEL expressions, and time-based filtering via the ReadChanges API. Storage backends include PostgreSQL 14+, MySQL 8, and SQLite in beta, with an in-memory adapter for development and testing. Official SDKs for Java, .NET, Node.js, Go, and Python provide type-safe client integration, while a Terraform provider enables infrastructure-as-code management of authorization stores and models. The built-in browser playground at port 3000 lets developers visually model authorization schemas, write relationship tuples, and test access control queries interactively before deployment. OpenTelemetry instrumentation integrates with existing monitoring infrastructure, and Helm charts simplify Kubernetes deployment. A VS Code extension provides syntax highlighting and validation for FGA model files, and GitHub Actions automate model testing in CI/CD pipelines. A CNCF incubating project with transparent governance. 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.

The entire wiki - content, code, and interface - is built from "tiddlers," small addressable units of information that link, transclude, tag, and filter into each other: TiddlyWiki is a non-linear personal notebook with a design philosophy unlike anything else in this catalog. Instead of pages in a hierarchy, you compose views by pulling tiddlers together on demand, which is why researchers, zettelkasten practitioners, and GTD devotees have sworn by it for two decades. The whole application is JavaScript, and the UI itself is written in hackable WikiText - customization goes as deep as rewriting the interface from inside the wiki. Self-hosting runs the Node.js version, which upgrades the classic single-HTML-file architecture in the ways that matter for a server: every tiddler is stored as an individual text file (Git-friendly, organizable), edits save through the HTTP API from any modern browser including phones, and one installation can serve multiple wikis blending shared and unique content. The plugin ecosystem covers graph visualizations, themes, languages, and hundreds of community extensions, declared per-wiki in a simple tiddlywiki.info file; the newer MultiWikiServer plugin adds multi-user accounts and tiddler sharing. Your notes stay usable for decades, independent of any corporation - the project's founding promise. BSD-licensed.

Hyperswitch from Juspay delivers the most comprehensive open-source payment orchestration stack available — a Rust-built platform that connects to Stripe, Adyen, Braintree, Worldpay, Checkout.com, Cybersource, and 120+ payment processors through a single API integration. Intelligent routing drives each transaction to the processor with the highest predicted authorization rate using rule-based, volume-based, and machine learning algorithms, while seamless failover and automatic retries recover revenue from declined transactions using 30+ parameters including decline codes, card BIN, transaction size, and region. The PCI-compliant card vault stores payment methods securely in a dedicated service separate from the main application server, and the reconciliation engine automates 2-way and 3-way matching with backdated support, staggered scheduling, and customizable audit-ready outputs. The Control Center dashboard provides visual workflow builders for routing rules, payment analytics, and operations management. Cost observability tools drill into scheme, interchange, and acquirer fees to detect anomalies and optimize processing costs. The modular architecture allows deploying individual components — routing, retries, vaulting, observability, or the full suite — without vendor lock-in. The web client SDK collects payment information with prebuilt UI components and supports WooCommerce integration. Deploy via Docker Compose with the app server, control center, card vault, and PostgreSQL. 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.

libSQL bridges the gap between SQLite's legendary simplicity and the server-accessible database model developers expect from PostgreSQL and MySQL, adding network access, replication, and vector search while maintaining full file format and API compatibility. The sqld (SQL daemon) component transforms SQLite into a network-accessible database server accepting queries via HTTP with JSON payloads, WebSocket connections, and a Hrana protocol optimized for low-latency edge access. Client libraries for TypeScript, JavaScript, Rust, Go, and Python connect to sqld identically to any traditional client-server database, while the LD_PRELOAD compatibility layer enables switching existing SQLite applications from local to remote mode without code changes. Embedded replicas synchronize a local SQLite copy inside your application process with the primary server, delivering sub-millisecond read latency while maintaining consistency through streaming replication. Bottomless replication continuously backs up database state to S3-compatible object storage with generation-based snapshots and WAL page shipping, providing point-in-time recovery without manual backup scheduling. Native vector search enables semantic similarity queries directly within SQL using cosine distance functions, eliminating the need for external vector database infrastructure. Read replica support distributes query load across multiple sqld instances, and integration with mvSQLite adds multi-version concurrency for high-availability deployments. Created by Turso with 17,100+ stars and active production deployment. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Deployed at thousands of enterprises across financial services, healthcare, government, and telecommunications, Apache NiFi is the industry-standard platform for building automated data pipelines through a visual drag-and-drop browser interface that requires zero coding for common integration patterns. The flow-based programming model connects over 300 built-in processors covering relational databases via ExecuteSQL and PutDatabaseRecord, Apache Kafka with PublishKafka and ConsumeKafka, HTTP endpoints through InvokeHTTP and ListenHTTP, cloud storage for AWS S3, Azure Blob, and Google Cloud Storage, SFTP/FTP file transfers, and JSON, XML, CSV, and Avro transformations. Data provenance tracking logs every routing decision, transformation, and delivery for every FlowFile, creating a searchable lineage graph from source to destination with full content replay capability for auditing and debugging. Guaranteed delivery uses configurable backpressure thresholds, prioritized queuing with latency or throughput optimization, and automatic retry with exponential backoff, ensuring no data loss even during downstream outages. The zero-leader clustering architecture distributes processing across nodes with automatic load balancing, while site-to-site protocol enables secure data transfer between NiFi instances across network boundaries. Security includes OpenID Connect and SAML 2.0 single sign-on, role-based access control with fine-grained policies per component, and TLS encryption for all communication. Custom processors can be written in Java and packaged as NAR bundles, or implemented directly in Python through the native scripting framework. 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.