What Synapse can do, then how it is built. Part 1 is a guided tour of the features: rendered diagrams (Mermaid and D2), clickable D2 walkthroughs, any code block openable in a full editor and run in a sandbox, step-by-step visualisations of that code, a lab that traces any program you paste, an interactive coding problem with a hidden test suite, architecture write-ups that live beside the diagram, and a library of copy-and-adapt D2 templates. Part 2 is the deep dive: architecture and low-level design drawn from the real code, the decision record and the price each decision paid, the technology stack, the git-to-production content pipeline, and a case study of the four-node homelab it runs on — with measured latency, real failure modes, and the outage that taught it fault tolerance. Every diagram matches the source; every number was measured.

A definitive system-design book that ramps from beginner to expert: DDIA-grade theory on an interview-ready spine, plus the production engineering behind real systems. 71 lessons across ten modules — foundations, data & distributed systems, infrastructure building blocks, named key technologies, patterns, fourteen end-to-end case studies with clickable C4 walkthroughs (closing with a capstone: the platform serving the book itself), production operations, and an interview playbook. Every claim sourced, every diagram rendered.

Data Structure & Algorithms Step by Step From Basics to Advanced.

Cross-cutting reference material that belongs to no single subject: the tooling around the platform, how it is set up, and what it has taught us.