A curated list of free system design learning materials and interview preparation problems and concepts.
A free, open-source alternative to Burp Suite: an intercepting proxy and web app security testing suite with Repeater, Intruder, Collaborator and a built-in OWASP ZAP scanner. Linux, AGPL-3.0.
Chat2DB is a free, cross-platform, local-first database client and SQL workspace for developers, DBAs, analysts, and data teams. Connect to 40+ databases, manage data, edit and run SQL, and use your own AI model to generate, explain, and optimize queries. Available on desktop, web, Docker, and CLI, with MCP support.
This comprehensive CKA learning path repo equips aspiring Kubernetes administrators with all the knowledge and resources to ace the CKA exam on the first try. Includes in-depth explanations, hands-on labs, and valuable study materials. Pass the CKA and unlock your Kubernetes potential today!
Open-source event-driven orchestration platform for scheduling and running data, AI, and infrastructure workflows defined in YAML.
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The official Java SDK for Model Context Protocol servers and clients. Maintained in collaboration with Spring AI
😮 Core Interview Questions & Answers For Experienced Java(Backend) Developers | 互联网 Java 工程师进阶知识完全扫盲:涵盖高并发、分布式、高可用、微服务、海量数据处理等领域知识
Open source transactional distributed database. Linear scalability and proven fault-tolerance on commodity hardware or cloud infrastructure without compromising performance.
Core IaaS engine and cloud infrastructure foundation of ZSvirt
Scalable, reliable, distributed storage system optimized for data analytics and object store workloads.
Empowering Data Intelligence with Distributed SQL for Sharding, Scalability, and Security Across All Databases.
Hazelcast is a unified real-time data platform combining stream processing with a fast data store, allowing customers to act instantly on data-in-motion for real-time insights.
A tool to help eliminate NullPointerExceptions (NPEs) in your Java code with low build-time overhead
Apache Nutch is an extensible and scalable web crawler
LITIENGINE 🕹 The Java 2D game engine.
An open source Valkey client library that supports Valkey, and Redis open source 6.2, 7.0 and 7.2. Valkey GLIDE is designed for reliability, optimized performance, and high-availability, for Valkey and Redis OSS based applications. GLIDE is a multi language client library, written in Rust with programming language bindings, such as Java and Python
索尼相机胶片配方应用 Recipe Lab 的中文汉化版:77 种胶片色彩配方,实时预览并写入相机,在所有拍摄模式长期生效。适配 A7R II / A7 系列 / A6000 系列等支持 PlayMemories 应用的机型。
Standalone Jellyfin Media Server & companion automation suite for Android ARM64.
crockTail is a passive OSINT (Open Source Intelligence) reconnaissance tool. Given a target domain, it aggregates publicly available information — DNS records, IP/ASN ownership, SSL/TLS certificate details, and domain registration data — into a single consolidated report.
a fast, scalable, multi-language and extensible build system
Test Automation Made Simple
Web-based notebook that enables data-driven, interactive data analytics and collaborative documents with SQL, Scala and more.
CrateDB is a distributed and scalable SQL database for storing and analyzing massive amounts of data in near real-time, even with complex queries. It is PostgreSQL-compatible, and based on Lucene.
The official AWS SDK for Java 1.x (In Maintenance Mode, End-of-Life on 12/31/2025). The AWS SDK for Java 2.x is available here: https://github.com/aws/aws-sdk-java-v2/
Framework for Evolutionary Message-Driven Microservices on the JVM
A graph database that supports more than 100+ billion data, high performance and scalability (Include OLTP Engine & REST-API & Backends)
🔥🔥 AllData可定义数据中台,以数据平台为底座,以数据中台为桥梁,以机器学习平台为工厂,以大模型应用为上游产品,提供全链路数字化解决方案。产品正式演示体验、社群咨询、商务采购:https://docs.qq.com/doc/DVHlkSEtvVXVCdEFo
An XMPP server licensed under the Open Source Apache License.
Apache Flume is a distributed, reliable, and available service for efficiently collecting, aggregating, and moving large amounts of log-like data
💬 DialogX dialog box component library, easy to use, more customizable, more scalable, easy to achieve a variety of dialog boxes. DialogX对话框组件库,更加方便易用,可自定义程度更高,扩展性更强,轻松实现各种对话框、菜单和提示效果,更有Material You、iOS、MIUI等主题扩展可选
React native bridge for AppAuth - an SDK for communicating with OAuth2 providers
Apache BookKeeper - a scalable, fault tolerant and low latency storage service optimized for append-only workloads
An open-source, code-first Java toolkit for building, evaluating, and deploying sophisticated AI agents with flexibility and control.
PolarDB-X is a cloud native distributed SQL Database designed for high concurrency, massive storage, complex querying scenarios.
🗻 Resize local images with React Native
Write Java. Run on GPUs. Fast.
🔖 It's a material-design about screen to use on your Android apps. A developer profile and application information easy to integrate.
A Jenkins plugin for interfacing with GitLab
StackGres Operator, Full Stack PostgreSQL on Kubernetes // !! Mirror repository of https://gitlab.com/ongresinc/stackgres, only accept Merge Requests there.
The Alibaba Cloud V1.0 SDK will soon enter the Basic Security Maintenance phase and is no longer recommended for use. V2.0 SDK is available here: https://github.com/aliyun/alibabacloud-java-sdk
The state-of-the-art Dashboard of Apache RoccketMQ provides excellent monitoring capability. Various graphs and statistics of events, performance and system information of clients and application is evidently made available to the user.
Infinispan is an open source data grid platform and highly scalable NoSQL cloud data store.
High Performance Software-Defined Block Storage for container, cloud and virtualisation. Fully integrated with Docker, Kubernetes, Openstack, Proxmox etc.
IoT DC3 — Connect the Physical World to AI. An open-source Industrial IoT Runtime for Physical AI: 36 protocol drivers, edge-to-cloud data delivery, and an MCP tool gateway so AI agents act on devices in a safe, controllable, traceable loop.
Scalable master data management, identity resolution, entity resolution, and deduplication using ML
Sakai is a freely available, feature-rich technology solution for learning, teaching, research and collaboration. Sakai is an open source software suite developed by a diverse and global adopter community.
GitLab4J API (gitlab4j-api) provides a full featured Java client library for working with GitLab repositories via the GitLab REST API
An artifact of fully-specified annotations to power static-analysis checks, beginning with nullness analysis.
Apache OFBiz is an open source product for the automation of enterprise processes. It includes framework components and business applications for ERP, CRM, E-Business/E-Commerce, Supply Chain Management and Manufacturing Resource Planning. OFBiz provides a foundation and starting point for reliable, secure and scalable enterprise solutions.
The JGroups project
Encrypted overlay filesystems implementation for Android. Also available on Tangled.
A tool for running android and iOS appium tests in parallel across devices... U like it STAR it !
Intelligent cloud testing made easy.
A scalable, mature and versatile web crawler based on Apache Storm
The next generation of tooling for Spring Boot, including support for Cloud Foundry manifest files, Concourse CI pipeline definitions, BOSH deployment manifests, and more... - Available for Visual Studio Code, Cursor, Eclipse, and Theia
AWS SaaS Boost is a ready-to-use toolset that removes the complexity of successfully running SaaS workloads in the AWS cloud.
Open source IaC Automation and Collaboration Software.
Graph+Semantics: Import/Export RDF from Neo4j. SHACL Validation, Model mapping and more.... If you like it, please ★ ⇧
Lucee is a high-performance, open-source CFML server written in Java. Supporting JDBC, Caching, Parallelism, HTTP, ORM, REST, S3 and dynamic Java integration, Lucee is great for developers aiming to build fast, scalable applications, delivering faster startup, rapid compilation and better runtime performance.