Typorithm · by ApplyDjinn
Understand it.
Type it. Recall it.
Turn a familiar concept into something you can explain and use. Small engineering lessons combine a clear idea, deliberate code practice and a check from memory.
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13
Learning paths
616
Topics
5,629
Activities
Learn the shape
Start with the idea, a worked code example and the details that make it useful.
Build the recall
Type deliberately, fill the missing pieces and choose an explanation that holds up.
Return with intent
Check the topic from memory. Revisit weaker results sooner and keep your own practice history.
Choose your path
One concept. One deliberate session.
95 topicsAlgorithms
Sorting, search, and dynamic programming — typing, recall, mistakes, and review.
41 topicsPatterns
Coding-interview patterns — two pointers, sliding window, frequency counter, and time complexity.
54 topicsData Structures
Arrays & hashing, linked lists, stacks, queues, trees, heaps, tries, and graphs.
18 topicsJavaScript
The language itself — closures, scope, promises, the event loop, classes, plus the Array/Object/Map/Set/String methods you reach for daily.
33 topicsInterview Questions
The full JS interview surface — gotchas, this & binding, closures, prototypes, the event loop, "implement X" classics, and tricky-output puzzles — plus applied challenge labs.
12 topicsFrontend
Build UIs by typing — React components, hooks, patterns, and Three.js.
73 topicsNode & Backend
Server-side JavaScript — Node.js and its web frameworks, Bun, and software architecture.
65 topicsDatabases & Data
Type the data layer — ClickHouse, MongoDB, InfluxDB, Redis, and Spark.
63 topicsDevOps & Infra
Ship and operate — Kubernetes, Terraform, Docker & CI/CD, Git, and Bash.
9 topicsComputer Networks
How the internet moves bytes — L3 IP addressing & routing, L4 TCP/UDP, plus HTTP, TLS, and DNS — by typing the diagnostic commands.
18 topicsSystem Design
Design systems that scale — fundamentals, scaling, data, communication, reliability, and the design interview.
111 topicsCybersecurity
Security as a craft — fundamentals, penetration testing, OSINT, and doxxing defense.
24 topicsAI · LLM
Large language models — engineering with the Claude SDK and how transformers work inside.
Connect learning to the market
A practice plan with a destination.
Use ApplyDjinn’s technology pages and live vacancies to choose what to practise. Typorithm helps with recall; a real project and a role-specific evidence pack help you show the work.