Free on YouTube · notes with every video

Courses

Every course is free on the channel. Each video has its own lesson page here with the chapters and a handwritten-style notes PDF. Create a free account to open the notes and track your progress.

13 lessons · 1.2 h

System Design

The foundations of system design for interviews: the 7-step framework, estimation, scaling, availability, CAP, networking, load balancers, CDNs, APIs, databases, indexes, replication, and data at scale: sharding, transactions, caching and object storage.

View the course

11 lessons · 1.3 h

Microservices

Monolith to microservices, step by step: when not to use them, domain-driven design, the strangler fig, REST vs gRPC, events, Kafka, API gateways, service discovery, database per service, and saga, CQRS, outbox and circuit breakers.

View the course

4 lessons · 0.5 h

Data Science

What a data scientist really does, the end-to-end workflow, NumPy in one lab, and the daily toolkit: pandas, SQL and data cleaning. Built around real datasets.

View the course

DSA in Java

13 lessons · LeetCode patterns

13 lessons

DSA in Java

Big-O, recursion, arrays, strings, hashing, linked lists, stacks, queues, binary search and trees, with Java code and LeetCode practice lists.

View the course