Enter a URL and get a dashboard of everything publicly discoverable about its security posture, server architecture, and technology stack: Web-Check is an all-in-one OSINT tool for analyzing any website. One scan surfaces IP info and server location, the full SSL certificate chain with issuing authority and validity, DNS records (A, MX, NS, CNAME, TXT) with DNSSEC status, HTTP response headers interpreted for security directives like HSTS, CSP, and X-Frame-Options, cookies and their flags, WHOIS domain info, robots.txt crawl rules, a sitemap-derived page map, the redirect ledger, open ports, traceroute, detected technologies, third-party trackers, associated hostnames, site performance, and even carbon footprint. Each card explains what the data means and why it matters, which makes the tool double as a security education resource - junior engineers learn headers and attack surfaces by scanning real sites. Practical uses span pre-deployment security audits (catch missing headers and misconfigurations before they ship), privacy compliance checks (identify trackers and cookie behavior for GDPR work), competitive tech-stack research, and network debugging via DNS and redirect inspection. Built by Lissy93 in TypeScript, it deploys as a single Docker container, and self-hosting keeps your reconnaissance targets and audit activity off third-party services.

A polished public status page without Statuspage prices or a heavyweight observability suite: Kener is a status and uptime monitoring system built with SvelteKit and Node.js. It runs 11 monitor types - API, Ping, TCP, DNS, SSL certificate, SQL query, Heartbeat, gRPC, and GameDig game-server checks among them - each with configurable intervals and thresholds. Incident management covers the full lifecycle: structured timelines from investigation through resolution, acknowledgements, and subscriber-visible updates, plus maintenance windows with RRULE-based recurring schedules and automatic status transitions. Notifications reach email, Slack, Discord, and custom webhooks through trigger-based workflows with template-driven messaging. One instance can serve multiple branded status pages - per product, team, or region - with custom logos, colors, and CSS, localization into 21 languages, timezone-aware displays, and server-rendered pages that stay fast and SEO-friendly. Operations tooling includes role-based access for teams, API key management, a secrets vault, analytics integrations (Google Analytics, Plausible, Umami, and others), and a REST API with 17+ endpoints for automating incidents and monitors from CI/CD. MIT-licensed; Docker deployment with Redis, SQLite by default, PostgreSQL or MySQL for production.

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.

Mixpanel, OneSignal, and Crashlytics in one self-hosted stack - Countly is an all-in-one product analytics and engagement platform where every byte of first-party data stays on your server. A Node.js application over MongoDB, it collects through ten battle-tested SDKs spanning iOS, Android, web JavaScript, React Native, Flutter, Unity, and desktop (plus a data write API for anything else), and has powered tens of thousands of mobile, web, and desktop apps since 2012. The analytics core covers sessions, custom events, views, user profiles, and real-time dashboards, with exploration tools built for product managers as much as analysts. What separates Countly from pure analytics tools is acting on the data without third parties: built-in push notifications send automated, transactional, and personalized messages to iOS (APNs), Android (Firebase), and Huawei devices, with the SDK handling token retrieval and permission flows automatically; crash reporting captures symbolicated native crashes on iOS and Android plus JavaScript errors, correlated with the same user and session data. Email reports keep stakeholders updated, and the plugin-based architecture means features load as modules. For GDPR-sensitive products, engagement without piping user data to advertising companies is the entire point. AGPL-licensed server, installable in minutes.

Send a document, receive a PDF: Gotenberg is a Docker-based, stateless HTTP conversion API trusted in production by thousands of companies and adopted by notable open-source projects. Send files as multipart/form-data, get a PDF back; Chromium, LibreOffice, and fonts are the container's problem, not yours. Headless Chromium handles URLs, HTML templates, and Markdown with pixel-perfect browser rendering: it executes JavaScript, loads web fonts, waits for network idle, a JS expression, or a DOM selector before rendering SPAs, and accepts injected cookies and HTTP headers for authenticated pages. LibreOffice converts 100+ office formats - .docx, .xlsx, .pptx, and legacy formats - with page-range extraction and PDF/A archival conformance. Built-in PDF engines round out the pipeline in every image variant: merge, split, rotate, flatten, encrypt, watermark, stamp, read/write metadata and bookmarks, plus Factur-X/ZUGFeRD e-invoicing and PDF/UA accessibility compliance. Screenshots of URLs and HTML come from the same endpoints. Zero-transfer pipelines stream files directly between S3, MinIO, or GCS presigned URLs and Gotenberg, bypassing your application entirely, and webhooks enable async processing. Statelessness means horizontal scaling is trivial - run as many replicas as your conversion volume demands. Three image variants (full, Chromium-only, LibreOffice-only) trim the footprint to what you actually use.

No cookies, no fingerprinting, no cross-site tracking, no personal data collection - Umami's privacy contract is the foundation of the open-source web analytics platform. IP addresses are hashed rather than stored, which makes it GDPR, CCPA, and PECR compliant by default - the consent banner can come off the site entirely. The tracking script is under 2 KB, roughly 20x smaller than Google Analytics, so measurement stops being a page-weight tax. The dashboard covers the core metrics - pageviews, visitors, bounce rate, visit duration, referrers, browsers, devices, and countries - with any date range and filtering by country or device. Beyond pageviews, custom events track clicks, form submissions, and signups via a data attribute or one JavaScript call, and advanced reports add funnels, user journeys, retention and cohort analysis, goals, and automatic UTM campaign tracking. Anonymous session views show individual visitor activity without identifying anyone. Teams share websites with role-based access, one instance manages unlimited sites, and a full REST API exposes every metric programmatically. MIT-licensed and self-hosted on PostgreSQL or MySQL via Docker, your analytics data never leaves your infrastructure.

The ad-riddled "free online tools" sites people paste sensitive text into and upload confidential PDFs to - OmniTools replaces that whole ecosystem with one self-hosted app. It bundles 50+ utilities behind one clean React/TypeScript interface: image tools (resize, convert, crop, edit), video and audio tools (trim, reverse, convert), PDF tools (split, merge, edit), text and list utilities (case converters, formatters, shufflers), plus date/time, math, and data-format helpers for JSON, CSV, and XML. The architectural decision that makes it trustworthy is that all file processing happens entirely client-side in the browser - the server only serves static assets, and nothing you process ever leaves your device. That design has a pleasant side effect: the host needs almost no resources (people run it on a Raspberry Pi Zero), because your browser does the work while the server just delivers files. The Docker image is a remarkable 28 MB, making it one of the fastest apps to deploy and cheapest to keep running. There are no ads, no tracking, no accounts, and no upload limits. With multi-language support and an MIT license, it works equally well as a personal toolbox or a team-wide internal utility portal - one URL that replaces a bookmark folder full of questionable converters. Actively developed with 50 contributors and 9,500+ GitHub stars.

Nearly two decades running engineering organizations: Redmine is the veteran open-source project management and issue tracker, a Ruby on Rails application (GPLv2) still in active development. Its core strength is configurability: define your own trackers (bug, feature, task, or anything else), issue statuses, and role-based workflows that control exactly which transitions each role may perform, then extend records with custom fields of every type. Issues support subtasks, relations (blocks, precedes, duplicates), watchers, categories, and full journaled history, with saved custom queries and cross-project filtering for slicing the backlog any way you need. Around the tracker sit Gantt charts and calendars, a roadmap driven by versions, per-project wikis, forums, news, and document repositories, plus time tracking with estimated versus spent hours and activity-based reporting. Multi-project support runs deep - subprojects, per-project modules, and granular role-based permissions - and repository integration (Git, Subversion, Mercurial) links commits to issues automatically. Email notifications, inbound email-to-issue creation, LDAP authentication, a REST API, and a large plugin and theme ecosystem round it out. Recent 6.x releases brought substantial query and rendering optimizations. Self-hosting keeps your entire project history in your own database, free of per-seat licensing.

GCHQ open-sourced its "Cyber Swiss Army Knife", and CyberChef became the web app security analysts, incident responders, and CTF players reach for when data needs decoding, decrypting, or dissecting. Its interface is four panes: paste or drag input (files up to 2GB), search a categorized library of hundreds of operations, drag them into a recipe with arguments, and read the output. Operations span Base64, hex, and XOR encoding; AES, DES, and Blowfish encryption; classical ciphers from Caesar to Railfence; hashes and checksums; compression; regex and string extraction of IPs, domains, and URLs; timestamp conversion; and parsers for IPv6, X.509 certificates, and more. Recipes chain arbitrarily - convert from a hexdump then decompress, decrypt AES pulling the IV from the cipher stream, or let the Magic operation auto-detect several layers of nested encoding. Auto Bake re-runs the recipe live as input or arguments change, Step executes one operation at a time for debugging, and flow control (forks, subsections, registers) applies different operations to different parts of the data. Recipes save to files or share as URLs encoding the full pipeline. Crucially, CyberChef is entirely client-side JavaScript - nothing uploads anywhere - and self-hosting guarantees an unmodified copy inside your own network, where malware artifacts belong.

ShareX and file uploads, next generation: Zipline is a Node.js/React/PostgreSQL server that turns screenshot sharing and file hosting into something you run yourself instead of renting from Imgur or a paid image host. The core workflow is built around ShareX: generate an .sxcu config from your account settings, import it, and every screenshot or clipboard capture uploads to your domain with a short link copied automatically. Uploads accept any file type, organized with folders and tags, with token-protected uploading, optional password protection, view-limited auto-deletion, image compression, metadata stripping, automatic video thumbnails, and chunked/partial uploads for large files. File URLs come in configurable formats - UUIDs, dates, random alphanumerics, original names, even zero-width spaces. A built-in URL shortener adds vanity slugs, passwords, view caps, and custom domains. Discord embeds are first-class: customize OG metadata titles, descriptions, and colors so links unfurl exactly how you want, and fire fully customizable Discord or HTTP webhooks on each upload. Authentication is serious: OAuth2 (Discord, GitHub, Google, OIDC), TOTP two-factor, and passkeys, with invite-based registration and per-user quotas for shared instances. Storage targets local disk or any S3-compatible backend, a full REST API automates everything, and custom themes plus a PWA round out the experience.

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.

The utilities engineers otherwise scatter across a dozen ad-laden websites - 80+ of them - live together in IT-Tools, one fast, polished web app. Crypto covers JWT decoding, MD5 through SHA-512 hashing, HMAC and bcrypt generation, RSA key pairs, and password strength analysis. Converters handle JSON to CSV, YAML, and TOML, Base64 files, URL encoding, HTML entities, color formats, and Docker run commands to Compose files. Generators produce UUIDv4, ULID, BIP39 mnemonics, QR codes (including Wi-Fi QR), and tokens; text tools include a regex tester, diff viewer, slug and case converters; web utilities parse URLs and user agents, look up HTTP status codes and MIME types, and inspect Open Graph metadata; plus a cron parser, chmod calculator, and more. The privacy argument is the point: JWTs contain user IDs, hashes derive from passwords, JSON dumps hold PII - exactly the inputs you least want a third-party utility site to log. IT-Tools is a frontend-only static bundle (Vue/TypeScript, GPL-3.0, 39k+ GitHub stars) served by Nginx in one container, so everything runs client-side on your infrastructure with nothing transmitted anywhere. New tools ship roughly monthly, and a scaffolding script makes adding custom ones straightforward.

Traffic analytics, real-user performance monitoring, and client-side error tracking - normally three tools - in one cookieless, privacy-first dashboard: Swetrix. The Community Edition ships the same core engine as the cloud product - a NestJS API with ClickHouse for high-volume event storage, MySQL for relational data, and Redis for caching, fronted by a React dashboard and a ~5 KB tracking script with official packages for 20+ frameworks including Next.js, WordPress, and Shopify. Traffic analytics cover pageviews, referrers, UTM campaigns, geolocation, sessions with page flows, funnels, and custom events - all anonymized server-side with no cookies, no cross-device tracking, and no consent banner required for GDPR compliance. Performance monitoring records real-user metrics per pageview: TTFB, DNS and TLS timing, and render times, so regressions surface in the same place as traffic. Error tracking captures unhandled JavaScript exceptions automatically with formatted stack traces, filename/line metadata, affected browsers and pages, first/last-seen timestamps, and a resolve workflow - replacing a separate error monitoring subscription for many teams. Alerts fire to email, Slack, Telegram, Discord, or webhooks on traffic spikes, new errors, and custom events. If Plausible covers your traffic questions but you also want to know why the site broke, Swetrix answers both.

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.

Team and product documentation on a fast Vue frontend with PostgreSQL storage: Wiki.js is a Node.js wiki engine. Its distinguishing trait is per-page editor choice: authors pick Markdown with live preview, a WYSIWYG visual builder for non-technical writers, or raw HTML, page by page. Native Git synchronization commits every page change to GitHub, GitLab, Bitbucket, Azure DevOps, or any Git remote - bi-directionally, so edits made in the repository flow back into the wiki - giving documentation version-controlled backup for free. Authentication coverage is among the broadest of any self-hosted wiki: local accounts with self-registration, social login via Google, GitHub, Discord, and Slack, and enterprise SSO through LDAP/Active Directory, SAML, CAS, Auth0, Okta, Azure AD, Keycloak, and generic OAuth2/OIDC, with optional MFA. Built-in full-text search runs on PostgreSQL with zero setup, and external engines like Algolia or Solr can substitute. Page history with visual version comparison, granular group-based permissions per path, nested navigation menus, 50+ integration modules, and full localization round it out. AGPLv3-licensed with a 28k-star community.

Wrap code in a flag, then toggle it per environment, per user, per segment, or by percentage - no redeploy required: Flagsmith is an open-source feature flag and remote config platform. Every flag doubles as remote config, carrying string, number, or JSON values, so functional and visual changes ship to production without a code push. Segments are the targeting engine: build them from stored user traits, then release to beta testers first, test in production by exposing features only to internal teams, or run canary deployments to a small percentage before going wide - segment membership changes instantly without app updates. Multivariate flags split traffic across two or more variations for A/B/n testing, with flag events flowing into Amplitude, Mixpanel, or Segment for analysis. SDKs cover 15+ languages including TypeScript, .NET, Java, Python, and Go, with framework support for React, Next.js, and mobile, plus local evaluation for latency-sensitive paths. Organizations, projects, and roles keep multi-team setups tidy. Core functionality - unlimited flags, remote config, targeting, multivariate flags - is BSD-3-Clause licensed with an explicit commitment that it stays open. Self-hosting suits privacy-conscious teams: flag rules and user traits stay on your infrastructure, deployable via Docker or Kubernetes with Helm.

The functions, config files, and one-liners you keep re-deriving finally get a searchable home: ByteStash is a self-hosted code snippet manager - a private Gist. Each snippet holds multiple code fragments, so a Docker Compose file, its .env template, and a plaintext usage note live together under one titled, categorized entry. Monaco-based syntax highlighting covers dozens of languages, from Python, TypeScript, Go, and Rust to YAML, Dockerfiles, Terraform, and Markdown. Retrieval is the point: filter by language or category, search titles and descriptions, and optionally include snippet contents in full-text search. Snippets can be pinned for quick access and shared via public links that recipients open without an account. Multi-user support runs on JWT authentication with optional OIDC single sign-on for teams on centralized identity, and a full CRUD REST API with Swagger documentation wires snippet retrieval into editors, scripts, and CI pipelines. Storage is a single SQLite database with optional encryption, and collections export as JSON or Markdown. A React frontend on a Node.js backend, deployed as one lightweight container.

Inspect a PostgreSQL database right now, without installing pgAdmin or exposing Postgres to the internet - pgweb answers that recurring need. It's a Go application from Dan Sosedoff, a decade in development, shipped as a single statically-linked binary with zero dependencies - the Docker image is essentially just the executable - that puts a clean browser UI in front of any PostgreSQL 9.1+ server. Connect via URL string or host/port credentials, and browse tables, views, and sequences from the sidebar; selecting a table shows its rows immediately alongside tabs for structure, indexes, and constraints. The Query tab executes arbitrary SQL with query history, and the Explain Query button renders the query plan - estimated cost, row counts, execution strategy - which makes pgweb a quick performance-triage tool, not just a browser. Results and entire tables export to CSV, JSON, or XML in a click. Connectivity is more flexible than its size suggests: native SSH tunneling (password or key) reaches databases behind firewalls, server bookmarks make switching instances instant, and an optional multi-session mode handles several databases concurrently. For a RepoCloud stack full of Postgres-backed apps, one pgweb instance is the universal inspection hatch. MIT-licensed, actively maintained.