backend

Deep dive into URL shortening algorithms. Implement Base62 encoding, handle collisions at scale, support custom aliases, and understand the math behind short code uniqueness and collision probability.

Add Redis caching and rate limiting to your URL shortener. Implement cache-aside pattern for sub-millisecond redirects, sliding window rate limiting, cache invalidation strategies, and Redis connection management.

Build a high-performance redirect engine and click analytics system. Learn 301 vs 302 redirects, non-blocking click tracking, user-agent parsing, geolocation, and analytics aggregation queries with PostgreSQL.

Add PostgreSQL and Prisma ORM to your URL shortener. Learn database schema design, migrations, indexing strategies, connection pooling, and how to replace in-memory storage with persistent database queries.

Add JWT authentication, user registration, and URL management to your URL shortener. Implement access and refresh tokens, bcrypt password hashing, auth middleware, user-scoped URLs, and API key generation.

Set up an Express + TypeScript project from scratch and build your first URL shortening API endpoint. Covers project scaffolding, folder structure, URL validation, Base62 short codes, redirect handling, and error middleware.

Master the durability foundation of distributed systems: Write-Ahead Log for crash recovery, Segmented Log for file management, and Low-Water Mark for log cleanup. With real-world examples from PostgreSQL, Kafka, and etcd.

Master advanced SQL features: window functions for rankings and running totals, CTEs for readable query composition, recursive queries for hierarchical data, and essential functions for real-world analytics.

Master distributed systems patterns from write-ahead logs to consensus protocols. A comprehensive roadmap covering durability, leader election, replication, partitioning, distributed time, and cluster coordination.

Master Yii2's frontend toolkit — GridView, ListView, DetailView, Pjax for dynamic data display, custom widgets, asset bundles for CSS/JS management, and integrating Bootstrap, Vue.js, or React with Yii2.