Open Source Projects using CSS
A curated collection of the 629 best open source software using CSS. Find the most popular and trending open source projects to learn from, contribute to, or use in your own projects.
AI-powered automation that lives in your Slack workspace
Stars
1,097Last commit
6 months agoLicense
Apache-2.0
Connect all your apps through Pearl, an AI assistant that automates workflows directly in Slack. No coding required - save 10+ hours weekly with intelligent task automation.
Open Source Alternative to:
Open-source feedback management for product teams
Stars
1,132Last commit
40 minutes agoLicense
Apache-2.0
Collect, organize, and prioritize user feedback to build better products. Self-hosted solution for seamless feature request management.
Open Source Alternative to:
Own your SES email analytics, from send to inbox
Stars
942Last commit
6 days agoLicense
Unknown
Track SES deliveries, bounces, opens and clicks in a self-hosted dashboard with real-time search, analytics and reputation monitoring.
Open Source Alternative to:
One self-hosted binary replaces Vercel, Sentry, and analytics tools
Stars
Stars growing quickly over the last 30 days854Last commit
13 minutes agoLicense
Apache-2.0
Self-hosted platform for small dev teams combining deployments, error tracking, analytics, session replay, uptime monitoring, and managed databases in one dashboard.
Open Source Alternative to:
Cookieless, privacy-first web analytics without the complexity
Stars
1,209Last commit
9 minutes agoLicense
AGPL-3.0
Privacy-first web analytics with real-time dashboards, session replays, error tracking, A/B testing, and GDPR compliance out of the box. No cookies, no consent banners.
Open Source Alternative to:
Lightning-fast React data grid for enterprise scale
Stars
1,029Last commit
2 months agoLicense
Unknown
High-performance React data table with server-side loading, tree data, pivoting, and advanced features. Handles billions of rows with minimal bundle size.
Schedule posts to every major social network, self-hosted
Stars
Stars growing quickly over the last 30 days720Last commit
2 hours agoLicense
AGPL-3.0
Plan, schedule, and auto-publish social media content across 10+ networks with a visual calendar, AI captions, team approvals, and self-hosting support.
Open Source Alternative to:
Your secure French personal cloud for complete data control
Stars
1,268Last commit
1 hour agoLicense
AGPL-3.0
Open-source personal cloud that automatically gathers all your data from third-party services. French-hosted with privacy-first design, no ads, and seamless device sync.
Open Source Alternative to:
Self-hosted encrypted backups with 70+ cloud storage options
Stars
Stars growing over the last 30 days860Last commit
15 hours agoLicense
Apache-2.0
Free, open-source backup solution with end-to-end encryption. Self-hosted control, supports 70+ cloud providers, automated incremental backups, and zero vendor lock-in.
Open Source Alternative to:
Transform your time tracking into actionable insights
Stars
919Last commit
29 days agoLicense
GPL-3.0
Advanced time tracking and productivity analytics tool that captures detailed work patterns, generates comprehensive reports, and helps optimize workflow efficiency.
Open Source Alternative to:
Flexible CMS for developers, powerful for clients
Stars
1,160Last commit
4 days agoLicense
Unknown
A versatile, open-source content management system with a powerful API, modular architecture, and intuitive interface for seamless web development.
Open Source Alternative to:
Fast, secure browsing with powerful organization features
Stars
1,081Last commit
5 months agoLicense
GPL-3.0
A modern browser combining minimalist design with smart features like profiles, spaces, and command palette. Full Chrome extension support and privacy-focused browsing.
Open Source Alternative to:
Open-source email API with enterprise deliverability
Stars
918Last commit
8 hours agoLicense
AGPL-3.0
Self-hosted email API alternative to AWS SES & Mailgun. Open-source AGPL-3.0 with enterprise features, automated deliverability, and cloud version coming 2026.
Open Source Alternative to:
Build AI agents and automate complex workflows seamlessly
Stars
Stars growing over the last 30 days1,037Last commit
29 minutes agoLicense
Apache-2.0
Create intelligent automation workflows combining AI agents with your favorite apps and services. Connect, automate, and scale your operations without complex coding.
Open Source Alternative to:
Agile project management for cross-functional teams
Stars
859Last commit
22 days agoLicense
MPL-2.0
Self-hostable agile project management tool with Kanban and Scrum boards, sprint planning, issue tracking, and reporting for teams of any size.
Open Source Alternative to:
Secure, deploy, and manage application secrets effortlessly
Stars
931Last commit
4 hours agoLicense
MIT
Open source platform for engineering teams to manage secrets and environment variables from development to production, with powerful integrations.
Open Source Alternative to:
Offline voice dictation that types into any app
Stars
738Last commit
4 days agoLicense
AGPL-3.0
Dictate into any app on Mac or Windows using on-device AI models. One-time purchase, 99+ languages, no subscription required.
Open Source Alternative to:
A delightfully rich and dynamic link-in-bio.
Stars
800Last commit
11 hours agoLicense
MIT
Build a dynamic link-in-bio page with a drag-and-drop editor. Integrate platforms to showcase live content and connect with your audience.
Open Source Alternative to:
Dictate faster and control your Mac with voice
Stars
656Last commit
28 days agoLicense
MIT
Free, open-source macOS voice assistant that transcribes speech, applies AI transformations, and controls apps hands-free. No subscription, no training required.
Open Source Alternative to:
Secure secret management with public key encryption
Stars
769Last commit
7 months agoLicense
MPL-2.0
Secure secret management platform with public key encryption, automated rotation, versioning, and real-time collaboration tools for development teams.
Open Source Alternative to:
Privacy-focused translation with offline capabilities
Stars
1,078Last commit
1 month agoLicense
BSD-3-Clause
Full-featured browser extension for translating web pages, text, and subtitles with offline mode, personal dictionary, and custom translator support.
Open Source Alternative to:
Revolutionizing data processing with Compute Over Data
Stars
874Last commit
3 days agoLicense
Apache-2.0
Bacalhau is an open-source platform for fast, cost-effective, and secure distributed computing, seamlessly integrating with Docker and WebAssembly workflows.
Visual regression testing made effortless
Stars
1,679Last commit
6 months agoLicense
MIT
Automated visual testing tool that detects UI changes, ensures consistency, and accelerates development workflows.
Open Source Alternative to:
Simplify server management with an intuitive interface
Stars
763Last commit
6 hours agoLicense
MIT
A user-friendly, open-source control panel for effortless server administration, designed for both beginners and experts.
Open Source Alternative to:
AI-native support infrastructure for modern SaaS
Stars
737Last commit
1 month agoLicense
AGPL-3.0
Open-source support platform combining AI and human agents. React components with shadcn/ui design philosophy, styled with Tailwind CSS for NextJS apps.
Open Source Alternative to:
AI coding agent that sees your live app and edits code
Stars
719Last commit
60 minutes agoLicense
Apache-2.0
Open-source AI coding agent that runs in your browser, sees your live DOM and app state, and makes real code edits from plain English descriptions.
Open Source Alternative to:
Feature management with GitOps for developers
Stars
812Last commit
23 hours agoLicense
MIT
Featurevisor is an open-source tool for managing feature flags, experiments, and remote configuration directly from your Git repository.
Open Source Alternative to:
Beautiful Kanban boards with seamless payment integration
Stars
663Last commit
2 months agoLicense
MIT
Organize projects with intuitive Kanban boards, powered by Supabase backend and Stripe payment processing for complete project management workflow.
Open Source Alternative to:
Persistent cloud VMs that hibernate and wake in seconds
Stars
Stars growing over the last 30 days568Last commit
5 hours agoLicense
Apache-2.0
Provides always-on virtual machines for AI agents with full OS access, persistent state, elastic CPU/memory resizing, and instant checkpoints.
Open Source Alternative to:
Self-hosted screen recording for seamless collaboration
Stars
1,016Last commit
2 years agoLicense
AGPL-3.0
Effortlessly create, share, and collaborate with screen recordings. Control your data with self-hosting or our secure cloud option.
Open Source Alternative to:
Visual website builder and CMS you can self-host
Stars
Stars growing over the last 30 days331Last commit
12 hours agoLicense
MIT
Build, manage, and host custom websites with a visual drag-and-drop builder and CMS. Self-host free or use managed cloud hosting.
Open Source Alternative to:
Build complete web apps with integrated graph database
Stars
828Last commit
9 days agoLicense
Unknown
Open-source low-code platform combining Neo4j graph database, visual schema editor, automatic REST APIs, and page rendering in one self-hosted environment.
A verified workspace where AI agents store and build knowledge
Stars
Stars growing quickly over the last 30 days561Last commit
1 day agoLicense
MIT
Busabase gives AI agents a shared database, knowledge base, and skills registry where every proposed change goes through human review before becoming canonical data.
Open Source Alternative to:
Your content engine for growing on Twitter at scale
Stars
771Last commit
10 months agoLicense
AGPL-3.0
Create, schedule & manage Twitter content at scale with AI assistance, beautiful visuals, and multi-account support. Perfect for busy founders.
Open Source Alternative to:
Take control of your finances, paycheck by paycheck
Stars
687Last commit
34 minutes agoLicense
FSL-1.1-MIT
Manage your money confidently with monetr, putting aside what you need and spending what you want
Open Source Alternative to:
S3-compatible object storage built with Swift
Stars
Stars growing over the last 30 days568Last commit
1 month agoLicense
Apache-2.0
Self-hostable, Apache 2.0-licensed object storage with S3 compatibility, a built-in web console, and horizontal scaling from single node to sharded cluster.
Open Source Alternative to:
Build and deploy AI agents through visual workflows
Stars
558Last commit
20 days agoLicense
Apache-2.0
Create powerful AI agents using an intuitive node-based interface that connects multiple LLMs and data sources for automated documentation and development workflows.
Secure open source email with advanced encryption & AI
Stars
660Last commit
10 hours agoLicense
AGPL-3.0
Open source professional email solution with PGP encryption, JMAP protocol, AI-powered responses, and advanced antispam protection. Control your data privately.
Open Source Alternative to:
Open source company management for high-performance startups
Stars
Stars growing over the last 30 days589Last commit
2 hours agoLicense
Apache-2.0
Operately is an open source platform that centralizes projects, goals, and processes, helping startups run efficiently without a COO.
Open Source Alternative to:
Real-time work and project management platform
Stars
591Last commit
10 minutes agoLicense
AGPL-3.0
Ever Teams offers an all-in-one solution for work management, time tracking, and team collaboration with integrations for popular tools.
Open Source Alternative to:
Visual regression testing for seamless UI development
Stars
643Last commit
4 days agoLicense
MIT
Automate visual testing, catch UI bugs early, and collaborate effortlessly with your team to maintain pixel-perfect interfaces.
Open Source Alternative to:
Federated short videos without corporate control
Stars
461Last commit
10 hours agoLicense
AGPL-3.0
Open-source, decentralized short-video platform that gives creators control. No ads, no lock-in, built on ActivityPub for true community ownership.
Open Source Alternative to:
Stellar Hosted – Managed Open Source software hosting in the EU: secure, compliant, fast.
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