Golang Backend Engineer, Fintech, web3

github

Kenneth Simpson • Peerlist

<p>This project features two Go microservices, a Producer and a Consumer, that communicate using gRPC. The services manage tasks within a PostgreSQL database and provide endpoints for Prometheus metrics and pprof profiling.</p><h3>Architecture &amp; Tooling</h3><ul><li><strong>Communication</strong>: Utilizes gRPC for efficient, typed, and bi-directional communication.</li><li><strong>Database</strong>: Employs PostgreSQL with sqlc for type-safe query generation and golang-migrate for schema migrations, embedded via go:embed.</li><li><strong>Monitoring</strong>: Integrates Prometheus and Grafana for metrics visualization.</li><li><strong>Profiling</strong>: Leverages net/http/pprof for generating flame graphs and performance analysis.</li><li><strong>Standard Library</strong>: Uses log/slog for structured logging, flag and os for configuration, and the standard http package for metrics and profiling. golang.org/x/time/rate is used for rate limiting.</li></ul><h3>GOGC and GOMEMLIMIT</h3><p>The GOMEMLIMIT is configured in docker-compose.yml to establish a soft memory limit for the Go runtime, aiding in the prevention of OOM errors in containerized environments. While GOGC can be adjusted, GOMEMLIMIT generally offers superior control over memory usage trade-offs by dynamically modifying GC frequency as the limit is approached.</p><h3>Build Flags &amp; Optimizations</h3><p>Extensive use of Go compiler and linker flags is made to optimize production binaries. Linker flags like -s (disables symbol table generation) and -w (disables DWARF generation) significantly reduce binary size when used together as -ldflags="-s -w". The flag -X 'main.Version=...' allows for dynamic injection of the version string at build time, accessible via the -version flag. Compiler flags include -pgo=auto for Profile-Guided Optimization, which uses captured CPU profiles to optimize hot functions.</p><h3>Profiling &amp; Flame Graphs</h3><p>Profiling endpoints are accessible on ports 6061 (Consumer) and 6062 (Producer). To capture CPU profiles and generate flame graphs, Go must be installed locally. The process involves using curl to capture the profile and then go tool pprof to visualize it, including flame graph views.</p><h3>Testing</h3><p>Unit tests can be executed using the command: go test ./... -v -cover.</p>

GitHub - ken2g60/marbl: gprc project · GitHub

<h3>This project provides a gRPC fintech internal service for user authentication and wallet management. It leverages Protocol Buffers for defining services, PostgreSQL for data storage, and Docker for containerization, ensuring a robust and scalable backend infrastructure.</h3><ul><li><strong>Language:</strong> Go 1.25.5</li><li><strong>Framework:</strong> gRPC with Protocol Buffers</li><li><strong>Database:</strong> PostgreSQL 14</li><li><strong>ORM:</strong> GORM</li><li><strong>Authentication:</strong> JWT (golang-jwt)</li><li><strong>Hashing:</strong> Argon2 with base64 encoding</li><li><strong>Containerization:</strong> Docker &amp; Docker Compose</li></ul><h3>Core Services:</h3><p><strong>User Service:</strong> Manages user authentication and account operations, including registration, login, profile management, and account deactivation. Key features include secure password hashing with Argon2 and JWT token generation/validation.</p><h3>RPCs for User Service:</h3><ul><li><strong>CreateUser:</strong> Registers a new user.</li><li><strong>LoginUser:</strong> Authenticates a user and provides a JWT token.</li><li><strong>UserProfile:</strong> Fetches the authenticated user's profile.</li><li><strong>UpdateProfile:</strong> Updates user profile information.</li><li><strong>DeactivateAccount:</strong> Deactivates a user's account.</li></ul><h3>Wallet Management Service:</h3><p>Handles wallet operations such as checking balances, depositing funds, withdrawing funds, and retrieving transaction history. It ensures real-time balance updates, transaction history tracking, and atomic balance updates with versioning.</p><h3>RPCs for Wallet Service:</h3><ul><li><strong>Balance:</strong> Retrieves the current wallet balance.</li><li><strong>Deposit:</strong> Adds funds to the wallet.</li><li><strong>Withdrawl:</strong> Removes funds from the wallet.</li><li><strong>TransactionHistory:</strong> Fetches the history of transactions for the wallet.</li></ul><h3>Key Features:</h3><ul><li>Secure password hashing using Argon2 with salt (base64 encoded).</li><li>JWT token generation and validation for secure API access.</li><li>User status management (active, inactive).</li><li>Real-time wallet balance updates.</li><li>Comprehensive transaction history tracking.</li><li>Atomic wallet balance updates with versioning to prevent inconsistencies.</li><li>Wallet status management (active, locked, suspended).</li></ul><h3>Development and Future Enhancements:</h3><p>The project includes a Makefile for easy service management (up, logs, down, ps). Future enhancements include multi-currency support, rate limiting, enhanced security features like 2FA, and analytics dashboards.</p>