DDIA Is Excellent Reading but Lacks Hands-On Practice, So a Companion Lab Was Built

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The author describes Designing Data-Intensive Applications as the best distributed systems book they have read, but argues it offers no way to test understanding. Without exercises, answer keys, or interactive failure scenarios, readers struggle to apply concepts like linearizability or two-phase commit under pressure. To fill this gap, the author built a companion practice lab covering 14 chapters in English and Persian. The lab includes 89 interactive step-through diagrams, 302 worked examples, and 47 design exercises with full solutions. It is positioned as a practice resource alongside the book, not a replacement or production system.

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