Open Source Projects using CSS
A curated collection of the 580 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.
Organize thousands of photos with ease
Stars
3,842Last commit
3 days agoLicense
GPL-2.0
Open source photo management software for organizing, sharing and managing large photo libraries. Perfect for teams, organizations and individuals.
Open Source Alternative to:
Transform any TV into professional digital signage
Stars
3,648Last commit
13 hours agoLicense
Unknown
Free open-source digital signage software that turns Raspberry Pi or old PCs into powerful display solutions. Manage images, videos, and web content easily.
Open Source Alternative to:
Effortless inventory management for modern businesses
Stars
2,982Last commit
13 hours agoLicense
AGPL-3.0
Simplify asset tracking, boost productivity, and gain real-time insights with our user-friendly, open-source inventory solution.
Open source modular logistics platform for faster app development
Stars
2,517Last commit
22 hours agoLicense
AGPL-3.0
Fleetbase is a comprehensive open source logistics suite offering API, TMS, driver and customer apps for streamlined operations and development.
Open Source Alternative to:
Self-hosted social media management without limits
Stars
3,524Last commit
5 months agoLicense
MIT
Create, schedule, and manage social media content from your own server with no subscription fees or usage restrictions.
Open Source Alternative to:
Open-source customer communication platform
Stars
3,560Last commit
2 months agoLicense
Unknown
Versatile messaging solution for businesses to engage customers through multiple channels, with AI-powered automation and analytics.
Open Source Alternative to:
Stripe payments, usage tracking, and paywalls in 3 functions
Stars
2,648Last commit
10 hours agoLicense
Apache-2.0
Simplify Stripe integration for AI startups with 3 functions, 0 webhooks. Build pricing plans in 30 minutes with usage tracking, credits, and feature controls.
Open Source Alternative to:
Monitor, debug, and scale LLM applications with ease
Stars
2,705Last commit
23 hours agoLicense
Apache-2.0
Open-source observability platform for GenAI and LLM applications. Real-time monitoring, distributed tracing, prompt management, and AI model evaluation built on OpenTelemetry.
Open Source Alternative to:
Fast and beautiful launcher for quick access to apps and tools
Stars
3,063Last commit
1 day agoLicense
MIT
A modern macOS launcher that provides instant access to applications, utilities, and system functions through an elegant and efficient interface.
Open Source Alternative to:
Open-source customer engagement platform for automation
Stars
2,910Last commit
5 months agoLicense
MIT
Dittofeed offers low-code tools for message automation across multiple channels, including powerful segmentation and personalization features.
Open Source Alternative to:
Visual website builder for effortless web design
Stars
2,305Last commit
15 hours agoLicense
MIT
Frappe Builder is an open-source, low-code website builder that enables users to create beautiful, responsive websites with an intuitive visual interface.
Open Source Alternative to:
Next-Gen CAPTCHA and Spam Protection, GDPR compliant
Stars
2,683Last commit
2 days agoLicense
MIT
ALTCHA offers cutting-edge spam and abuse protection for websites and apps, with privacy-friendly CAPTCHA alternatives designed for GDPR compliance.
Open Source Alternative to:
Self-hosted home automation without the cloud
Stars
3,154Last commit
10 hours agoLicense
Apache-2.0
Privacy-first home automation platform that runs locally on your hardware, supports Zigbee, Matter, and MQTT, and lets you automate your home without coding.
Open Source Alternative to:
Create engaging product tours and user onboarding experiences
Stars
2,278Last commit
17 hours agoLicense
AGPL-3.0
Open-source platform for building interactive product tours, tooltips, and in-app guides to improve user engagement and feature adoption without complex coding
Open Source Alternative to:
Modern open-source billing platform for hosting businesses
Stars
2,243Last commit
14 hours agoLicense
MIT
Automate subscriptions and manage payments with a flexible, open-source billing system designed specifically for hosting providers.
Open Source Alternative to:
Open-source personal finance management tool
Stars
2,911Last commit
3 months agoLicense
GPL-3.0
Self-hosted alternative to Mint and YNAB for budgeting and building wealth while maintaining full control of your financial data.
Open Source Alternative to:
AI agents that transform merchant risk decisions at scale
Stars
2,423Last commit
10 days agoLicense
Unknown
Reduce fraud, accelerate underwriting, and maintain compliance with AI-driven merchant risk intelligence for PSPs, banks, and fintechs.
Open Source Alternative to:
Create, sell, and manage online courses with full control
Stars
2,186Last commit
5 days agoLicense
AGPL-3.0
Open-source LMS for building and selling courses with a block-based editor, built-in payments, AI tools, analytics, and white-labeling. Self-host or use the cloud.
Open Source Alternative to:
Create beautiful images of your code
Stars
2,344Last commit
3 days agoLicense
MIT
Turn your code into beautiful images. Choose from a range of syntax colors, hide or show the background, and toggle between a dark and light window.
Open canvas for designing and building web apps
Stars
2,616Last commit
2 days agoLicense
Apache-2.0
Design and build web applications on an open canvas with AI-powered tools, Figma integration, pixel drawing, and a modular SDK built for extensibility.
Open Source Alternative to:
Get audit-ready for SOC 2, ISO 27001, HIPAA, and GDPR
Stars
1,874Last commit
11 days agoLicense
AGPL-3.0
AI-driven compliance platform that automates evidence collection, policy generation, and continuous monitoring across 580+ integrations for SOC 2, ISO 27001, HIPAA, and GDPR.
Open Source Alternative to:
Design, prototype, and test user experiences with ease
Stars
2,682Last commit
1 day agoLicense
GPL-3.0
Quant-UX is an open-source tool for creating interactive prototypes, conducting user tests, and analyzing results to improve UX design.
Open Source Alternative to:
Route GenAI traffic with confidence using open source
Stars
1,943Last commit
12 hours agoLicense
Apache-2.0
Open source gateway built on Envoy for routing application traffic to GenAI services. Supports 16+ LLM providers including OpenAI, Anthropic, AWS Bedrock.
Open Source Alternative to:
Free DNS management and URL shortening platform
Stars
2,279Last commit
3 months agoLicense
MIT
WR.DO offers free domain name distribution and short URL generation, built on Cloudflare's infrastructure for reliability and speed.
Open Source Alternative to:
Self-hosted email platform with visual editor & analytics
Stars
2,052Last commit
3 days agoLicense
AGPL-3.0
Free open-source email platform for newsletters and transactional emails. Self-hosted alternative to Mailchimp with visual MJML editor, A/B testing, and analytics.
Open Source Alternative to:
Complete IT infrastructure monitoring made simple
Stars
2,347Last commit
10 hours agoLicense
GPL-2.0
Monitor your entire IT infrastructure with 2,000+ plugins, automated discovery, and scalable architecture. Open source and enterprise solutions available.
Open Source Alternative to:
Simplify AWS SES email management with ease
Stars
2,298Last commit
2 months agoLicense
MIT
A comprehensive platform for managing transactional and marketing emails through AWS SES, featuring customer data management, SMS capabilities, and workflow automation.
Open Source Alternative to:
Powerful, customizable web analytics for your site
Stars
2,684Last commit
10 hours agoLicense
GPL-2.0
Open-source web analytics platform offering comprehensive visitor tracking, customizable dashboards, and data ownership for websites and applications.
Open Source Alternative to:
Build privacy-compliant cookie banners with full control
Stars
1,858Last commit
4 days agoLicense
Apache-2.0
Open source consent management framework for modern web apps. Framework-agnostic, fully customizable, and performance-first with no vendor lock-in.
Open Source Alternative to:
Self-hosted error tracking for full control and scalability
Stars
2,024Last commit
13 hours agoLicense
Unknown
Bugsink offers real-time error tracking with self-hosting capabilities, allowing easy installation and connection to any app using Sentry-compatible SDKs.
Open Source Alternative to:
AI-native CRM/ERP foundation with 80% already built
Stars
1,655Last commit
14 hours agoLicense
MIT
A modular CRM/ERP framework built on Next.js and TypeScript that encodes hundreds of architectural decisions so dev teams can ship production features in days, not months.
Open Source Alternative to:
GPU orchestration across clouds, Kubernetes, and on-prem
Stars
2,216Last commit
13 hours agoLicense
MPL-2.0
Unified control plane for AI compute that provisions and schedules GPU workloads across any cloud, Kubernetes cluster, or bare-metal server.
Open Source Alternative to:
Unified API development ecosystem for modern teams
Stars
2,607Last commit
6 months agoLicense
AGPL-3.0
All-in-one platform for API testing, documentation, and collaboration, simplifying the entire API development lifecycle.
Open Source Alternative to:
Local-first, offline-first no-code database platform
Stars
2,972Last commit
1 year agoLicense
AGPL-3.0
Build and manage custom databases with ease, create type-safe APIs, and develop applications quickly
Open Source Alternative to:
Comprehensive open-source HR management solution
Stars
1,332Last commit
19 hours agoLicense
LGPL-2.1
Horilla is a free, open-source HRMS that streamlines HR processes, from recruitment to offboarding, with customizable modules.
Open Source Alternative to:
Build your custom learning academy in minutes
Stars
1,658Last commit
11 hours agoLicense
AGPL-3.0
Open source LMS designed for companies and training organizations. Create, manage, and deliver courses with AI support, customizable dashboards, and collaborative features.
Open Source Alternative to:
Code with Claude, Codex, Gemini, and more in one workspace
Stars
1,580Last commit
11 hours agoLicense
MIT
Desktop coding workspace that connects to AI subscriptions you already have, with parallel agents, worktrees, one-click PRs, and multi-project management.
Open Source Alternative to:
Automated localization for modern development teams
Stars
2,030Last commit
3 months agoLicense
MIT
A developer-focused localization platform that automates translation workflows within your existing development pipeline and CI/CD processes.
Open Source Alternative to:
Open-source email marketing for the privacy-conscious
Stars
2,190Last commit
2 days agoLicense
AGPL-3.0
Self-hosted newsletter platform with powerful features, data protection, and full control over your mailing lists and campaigns.
Open Source Alternative to:
Simplify your workflow with offline Kanban boards
Stars
2,002Last commit
6 days agoLicense
GPL-3.0
Kanri is a free, open-source personal Kanban app that works offline, offering a modern and simple experience while respecting your privacy.
Open Source Alternative to:
Full-text search API with real-time indexing and crawling
Stars
1,908Last commit
8 days agoLicense
Apache-2.0
Cloud search API and crawler service supporting billions of documents, real-time indexing, autocomplete, faceted filtering, and multi-language text across any application.
Open Source Alternative to:
Open-source message stream built on Postgres
Stars
2,187Last commit
6 months agoLicense
MIT
Sequin offers a feature-rich messaging system with a simple HTTP API, providing RabbitMQ-like functionality without adding complexity to your stack.
Open Source Alternative to:
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