Book

Applied Computer Science

Production systems, built from first principles A narrative companion to the Applied CS curriculum: the engineering concepts behind production software, data, ML, and infrastructure systems. Part I teaches the cross-cutting ideas — concurrency, type systems, memory, error handling, testing, performance — once, comparatively across six languages; the rest are field guides and domain deep-dives. Every chapter is cross-linked to a real, runnable implementation in the companion projects. The AI-engineering material lives in the separate AI Engineering book.

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Applied Computer Science — Production systems, built from first principles — by James Hu

What's inside

The book is organized into 6 parts that map roughly to career progression.

Who it's for

  • Engineers who want the concepts behind production systems, not just syntax
  • Polyglot developers working across Python, TypeScript, Go, Java, C++, and Rust
  • Backend and data engineers strengthening their systems fundamentals
  • Self-taught developers filling in computer-science foundations
  • CS students who want to see how the theory shows up in real systems
Part I

Cross-Language Foundations

The cross-cutting concepts — concurrency, type systems, memory, error handling, testing, performance — taught once, comparatively across all six languages.

Part III

Data Engineering

Orchestration, processing, warehousing, streaming, quality, and the infrastructure behind production data systems.

Part IV

Machine Learning Engineering

From ML foundations and deep learning to distributed training, GPUs, and production ML systems.

Part V

Cross-Cutting Concerns

What production demands across every system: CI/CD, observability, security, and cost.

Part VI

Infrastructure

Containerization, orchestration, and benchmarking the systems that run it all.