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Data Structures & AlgorithmsComplexity analysis up to graphs and DP.Operating SystemsProcesses, scheduling, memory and concurrency.Database Management SystemsRelational modelling, transactions and indexing.Computer NetworksFrom wires and radio waves up to the web.

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AI Inference EngineeringQuantization, batching and KV caching in production.System DesignScalable systems from first principles.Context EngineeringDesigning the context that LLMs actually reason over.Docker & KubernetesContainers and orchestration, explained.

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Operating Systems

Foundations of Operating Systems3

Processes & Threads4

Inter-Process Communication3

Concurrency & Synchronization4

CPU Scheduling4

I/O & Disk Scheduling3

How I/O devices actually work, from the OS's point of view
Disk scheduling algorithms — choosing the order that hurts least
RAID and keeping data alive when disks fail

Memory Management4

Virtual Memory3

Building Your Own OS in C++6

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Operating Systems

Foundations of Operating Systems3

Processes & Threads4

Inter-Process Communication3

Concurrency & Synchronization4

CPU Scheduling4

I/O & Disk Scheduling3

How I/O devices actually work, from the OS's point of view
Disk scheduling algorithms — choosing the order that hurts least
RAID and keeping data alive when disks fail

Memory Management4

Virtual Memory3

Building Your Own OS in C++6

Learn Operating Systems I/O & Disk Scheduling

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How I/O devices actually work, from the OS's point of view

What a disk really looks like mechanically, why I/O is agonizingly slow compared to the CPU, and the buffering trick that hides it.

9 min readUpdated 2026-09-03operating-systemsiodiskfundamentals