Technical Support Engineer

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 course built around 75 coding interview questions chosen for coverage across 18 topic areas, from arrays and sliding window to graphs, backtracking, dynamic programming and tries. Each question has a step-by-step algorithm, a walkthrough and complexity analysis, with solutions in six languages. It suits candidates with a few weeks before an interview who need a balanced, finite problem set rather than an endless list.

• Job search
• DSA

A quick-revision companion to the DSA roadmap in nine chapters: complexity, arrays and hashing, linked lists, stacks and queues, recursion, sorting and searching, trees and heaps, graphs, coding patterns, dynamic programming and timed practice habits. Costs are stated for every structure and algorithm, in Python, Java, C++ or JavaScript editions. Use it after each roadmap stage and before a contest or coding round.

• Programming
• DSA
• Web

An eight-stage path from Big-O through arrays, hashing, recursion, trees, graphs, coding patterns and dynamic programming to timed, mixed practice, in Python, Java, C++ or JavaScript. It suits students and developers who can write code but freeze on problems with no obvious library call. By the end you can pick the right data structure, recognise common problem shapes and solve a medium problem in about 35 minutes with edge cases tested.

• Programming
• DSA
• Web

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 how databases work underneath: storage and page layout, indexing, transactions and ACID, concurrency control, partitioning and sharding, replication and consistency, consensus and leader election, recovery, and the main NoSQL families. It ends with case studies designing the databases behind Quora, TikTok, Airbnb and Snapchat. It suits engineers who want their database choices in system design answers to be defensible rather than hand-waved.

• System design
• Databases
• Backend
• Job search