Open-source alternatives to PPHC

Nebula is a distributed graph database designed for storing and querying massive volumes of interconnected vertices and edges across a horizontally scalable cluster. It functions as a Kubernetes-native database and a distributed graph analytics engine, utilizing a Raft-based distributed store to ensure strong consistency and high availability. The system features an OpenCypher query engine for performing complex graph traversals and pattern matching. It distinguishes itself with a decoupled compute-storage architecture and a shared-nothing distributed design, allowing query processing and dat

This project is a technical programming guide and educational resource focused on Go internals, runtime mechanisms, and advanced language features. It provides detailed conceptual analysis of the language's execution model, including its scheduler, memory escape analysis, and garbage collection mechanisms. The material distinguishes itself through deep dives into high-concurrency system design, exploring the implementation of worker pools and communication channels. It also covers low-level network programming with a focus on I/O multiplexing and TCP state management, alongside a study of dis

This project serves as a comprehensive technical reference for the architecture and design of data-intensive applications. It provides a structured analysis of the fundamental principles required to build reliable, scalable, and maintainable software systems, covering the core trade-offs inherent in modern data infrastructure. The repository explores the mechanics of distributed data management, including strategies for replication, partitioning, and achieving consensus across multiple nodes. It details the design of storage engines, indexing techniques, and transaction management models, whi

RocketMQ is a cloud-native distributed messaging platform and streaming engine. It functions as a distributed transactional queue that ensures atomicity between local transactions and message delivery, and serves as an MQTT IoT message broker to bridge lightweight device traffic into high-performance data streams. The system is distinguished by a Kubernetes-native architecture that decouples compute from storage to allow independent scaling of traffic and data retention. It utilizes a tiered storage model to offload older data to remote storage and employs quorum-based replication and automat

TiKV is a cloud-native distributed transactional key-value store and storage engine. It provides a distributed database designed for horizontal scalability and strong consistency across a cluster of physical nodes. The system uses a Raft-based consensus mechanism to maintain data availability and state synchronization. It ensures ACID compliance for distributed transactions through a two-phase commit workflow and manages data distribution via multi-Raft sharding. The engine handles massive datasets using automated range splitting and cluster load balancing to distribute data across different

This project is a learning platform and study guide focused on the principles of distributed systems and software architecture. It provides a collection of architectural scenarios and technical problem statements designed to help engineers practice system design, capacity planning, and trade-off analysis for high-scale services. The repository distinguishes itself by offering functional prototypes and models for complex engineering challenges. Rather than providing purely theoretical documentation, it includes executable representations of system components—such as storage services, load bala

Doris is a distributed SQL data warehouse designed for high-performance analytical workloads and real-time data processing. It functions as a unified platform that integrates traditional relational warehousing with lakehouse query capabilities, allowing users to execute analytical operations directly against external data lakes without requiring data migration. The system distinguishes itself through a shared-nothing, massively parallel processing architecture that utilizes vectorized query execution and columnar storage to maintain sub-second latency. It supports dynamic schema evolution, en

VictoriaMetrics is a high-performance, scalable time series database and observability platform designed for long-term storage and analysis of metric, log, and trace data. It functions as a unified backend for monitoring ecosystems, offering full compatibility with industry-standard protocols and query languages. The system is built to handle massive data volumes through a distributed architecture that supports horizontal scaling and efficient data lifecycle management. The platform distinguishes itself through a storage engine that utilizes consistent hashing for data sharding and log-struct

This project is a comprehensive framework for engineering financial data pipelines, designed to automate the collection, cleaning, and synchronization of large-scale market datasets. It functions as a quantitative trading data engine, providing the infrastructure necessary to manage historical and real-time asset pricing information for research and machine learning workflows. The system distinguishes itself through a configuration-driven approach to orchestration, allowing users to manage complex data acquisition tasks across multiple financial providers. It features resilient middleware tha

The AWS Cloud Development Kit is an infrastructure-as-code framework that enables developers to define and provision cloud resources using familiar programming languages. By utilizing construct-based synthesis, it translates high-level, object-oriented code into declarative templates, allowing for the automated management of complex cloud environments through a centralized, code-driven control plane. The framework distinguishes itself through its ability to model infrastructure as a dependency-aware resource graph, ensuring that components are provisioned and updated in the correct order. It

JavaSourceCodeLearning is a collection of deep-dive analyses and architectural breakdowns focusing on the internal source code of major Java frameworks and distributed systems. It provides a systematic study of the Java Development Kit internals, the Spring ecosystem, Netty's network architecture, and the distributed system mechanics of Kafka. The project focuses on the implementation of core infrastructure, including partition management, replica consistency, and log storage. It examines asynchronous event-driven network programming, I/O multiplexing, and the internal logic used for dependen

InternetArchitect is an educational collection of documents and source code designed as a high concurrency architecture course. It serves as a distributed systems implementation guide, providing technical patterns and practical examples for designing scalable internet architectures that maintain stability under heavy traffic loads. The project focuses on high-performance database optimization and microservices design patterns. It covers strategies for reducing latency and increasing throughput via database sharding and proxy layers, as well as coordinating global state across distributed clus

The Accidental CTO is a comprehensive collection of guides and frameworks focused on distributed systems architecture, resilience engineering, and system observability. It provides strategies for scaling applications from thousands to millions of users while maintaining high availability. The project offers specific methodologies for managing data volume through replication, sharding, and caching. It includes a framework for analyzing cloud infrastructure spending and evaluating transitions to self-hosted environments to reduce operational expenses. The resource covers the implementation of

This repository is a learning resource and collection of hands-on exercises illustrating cloud-native architecture, microservice composition, and container design patterns for distributed environments. It provides implementation blueprints demonstrating sidecar, adapter, and ambassador patterns for applications deployed within Kubernetes containers. The materials cover traffic management capabilities such as routing requests through proxy containers, splitting traffic between production and experimental servers, enforcing rate limits, and isolating failing services using circuit breakers. Add

Neon is a serverless PostgreSQL database platform designed with a decoupled storage and compute architecture. It functions as a multi-tenant system that isolates data and compute resources for independent users on shared cloud infrastructure, utilizing a specialized PostgreSQL storage engine. The platform features a database branching system that allows for the creation of isolated, instant copies of a database for testing and development. It further distinguishes itself with an HTTP-based SQL gateway, enabling the execution of queries via HTTP requests and JSON responses without the need for

Akka.NET is an actor model framework used for building concurrent and distributed applications. It functions as a distributed computing platform and state manager that enables isolated actors to communicate via asynchronous message passing, ensuring thread-safe state management without manual locks. The project is distinguished by its decentralized coordination capabilities, including a distributed state manager that uses sharding and dynamic rebalancing to maintain high availability. It incorporates an event sourcing engine that persists state as a sequence of events in an append-only log an

Talent Plan provides guided training programs and curricula centered on distributed database design, systems programming, and open source contribution workflows. The project offers a distributed systems education program consisting of curated courses and labs focused on database internals. The curriculum emphasizes the use of the Rust language for building high-performance networked applications and implementing distributed algorithms. It integrates educational materials on version control, community governance, and the specific processes required to contribute to public software projects. T

This repository serves as a technical reference for designing scalable, resilient, and performant software within distributed service environments. It provides a collection of architectural patterns and structural strategies intended to guide the development of complex, decoupled systems that maintain high availability and data integrity under heavy load. The resource focuses on the core principles of microservices architecture, offering guidance on managing communication between independent software components through both synchronous and asynchronous messaging. It details strategies for mai

This is a Raft consensus library and distributed consensus engine implemented in Go. It provides the primitives necessary to build fault-tolerant distributed services by implementing a replicated state machine that ensures a group of servers agree on a shared system state through leader election and log replication. The project distinguishes itself through a pluggable architecture for storage backends and snapshot storage, decoupling the consensus logic from physical persistence. It includes specialized mechanisms for leadership transfer, protocol version management to support rolling upgrade

This project is a distributed, document-oriented database system designed to store information in flexible, hierarchical structures. It supports horizontal scaling through automated sharding and maintains high availability across global clusters using a multi-node replication protocol. By executing multi-document operations as atomic units, the system ensures data integrity and consistency across distributed environments. The platform distinguishes itself by integrating advanced vector-based indexing, which enables semantic similarity searches alongside traditional geospatial and lexical quer

This project is a collection of reference implementations and practical guides for building enterprise Java applications using the Spring Boot framework. It serves as a backend project gallery and implementation guide, providing a set of architectures for common server patterns. The repository distinguishes itself through a focus on distributed system design, offering examples for global unique identifier generation, distributed caching, and full-text search. It also includes templates and examples for creating custom Spring Boot starters to encapsulate shared dependencies and configurations

Seastar is a C++ server application framework and asynchronous programming library designed for building high-performance, shared-nothing server applications. It functions as a high-performance I/O engine providing direct disk and network access through a shared-nothing framework that partitions data and execution across CPU cores. The framework distinguishes itself through a thread-per-core architecture that eliminates locking and resource contention by assigning one execution thread to each physical CPU core. It implements a userspace TCP/IP stack and kernel-bypass techniques, integrating w

TiKV is a distributed transactional key-value store designed for horizontal scalability and high availability. It functions as a storage engine that maintains massive datasets across a cluster of physical nodes, ensuring that information remains accessible and consistent even when individual hardware components fail. The system utilizes a consensus-based replication model to synchronize data across nodes, ensuring that all replicas agree on the order of operations. It manages data distribution through a sharding mechanism that partitions large datasets into smaller groups, each governed by in

Memcached is a high-performance, distributed, in-memory key-value storage and request routing engine. It functions as a volatile data store designed to accelerate dynamic applications by caching objects in RAM, thereby reducing backend database load and providing sub-millisecond response times. The system utilizes a specialized architecture that organizes memory into fixed-size slabs to minimize fragmentation and maximize throughput for high-concurrency workloads. The project distinguishes itself through a multi-threaded, lock-friendly design that scales across CPU cores and supports complex

brpc is a high-performance C++ RPC framework and network programming library designed for building distributed systems. It functions as a multi-protocol RPC server capable of hosting and detecting multiple communication protocols, including gRPC, Thrift, HTTP, Redis, and Memcached, on a single TCP port. The project distinguishes itself through high-throughput data transport and memory efficiency, utilizing RDMA-based transport to bypass the kernel TCP stack and zero-copy memory management to eliminate data duplication. It also implements the Raft algorithm for consensus-based state replicatio

Apache Pulsar is a cloud-native distributed pub-sub messaging system designed for high-performance data ingestion. It functions as a geo-replicated data streamer and a multi-tenant event streaming platform, providing a serverless stream processing engine and a tiered storage messaging broker. The system distinguishes itself by separating serving layers from storage layers to allow independent scaling of compute and data retention. It features native geo-replication to synchronize messages across different geographical regions and employs a multi-layered tenant isolation model using authentica

Complete-System-Design is a comprehensive software architecture study guide and learning curriculum designed for engineering education and interview preparation. The repository provides structured reference materials covering fundamental system principles, scalability patterns, and asynchronous load distribution techniques for large-scale systems. The content is organized into multi-day study tracks, hierarchical directories, and modular curricula composed of markdown documents. It features methodical interview frameworks with decision trees for solving open-ended architectural problems, alo