Associate QA Engineer

A foundations course that builds eleven core data structures from the ground up (arrays, matrices, stacks, queues, linked lists, trees and BSTs, hash tables, hash sets, heaps, graphs and tries), then covers sorting, searching, greedy and divide and conquer. Every chapter has practice problems, flashcards and an assessment. It suits students and career switchers whose foundations came from tutorials and who find pattern courses move too fast.

• Job search
• DSA
• CS fundamentals

A browsable practice library of coding problems that can be filtered by pattern, data structure, difficulty and company, so you can drill exactly the weakness you found this week. Patterns include two pointers, sliding window, hash maps, stacks, backtracking and greedy algorithms, with company filters for Google, Meta, Microsoft, Amazon, Oracle and LinkedIn. Free to browse, with an in-browser editor and solutions.

• Job search
• DSA

A free newsletter of short, focused posts on system design and problem solving, from the team behind the Grokking courses. Recent posts cover company interview processes (such as OpenAI and Anthropic roles), the most asked mobile system design questions and preparation plans, each linking to a fuller article on the blog. It suits engineers who want a steady, low-effort way to keep system design and interview topics fresh between deeper study sessions.

• System design
• DSA

A text based course on the classic object oriented design patterns, 22 in all across creational, structural and behavioural groups, with a real world problem, class diagram, pros and cons and code in Python, Java, JavaScript and C++ for each. It suits developers who meet patterns in code reviews and want to apply them where they help rather than everywhere, and those preparing for low level design discussions.

• System design
• CS fundamentals
• Backend

The official Android developer guides and reference: Jetpack Compose UI, data and files, permissions, navigation, background work with WorkManager, camera, location, connectivity, testing, performance tools and releasing your app, plus guides for phones, tablets, foldables, Wear OS, TV, cars and XR. It suits developers who have finished a beginner course such as Android Basics with Compose and need accurate, current answers while building real apps.

• Mobile
• Testing

A popular English channel for native Android development with Kotlin: Jetpack Compose, Kotlin Flows, MVVM architecture, testing, storage, security, Kotlin Multiplatform and Spring Boot with Kotlin. Philipp explains why code works, not just how. It suits Android learners past the basics and Kotlin developers who want production-quality habits.

• Web
• Mobile
• Testing
• Backend