Building resilient systems with Sam Newman

Brought to You By: • turbopuffer – a vector and full-text search engine built on object storage. It’s fast, cheap, and extremely scalable. • Entire – Git hosting, rebuilt for the agentic era. Every agent session, prompt and tool calls: stored in your repo. • Antithesis – verify your system’s correctness without human review or traditional integration tests – and avoid bugs or outages. — Sam Newman wrote one of the most-read books about microservices (“ Building Microservices ”), but he calls them an architecture of “last resort.” In this episode of the Pragmatic Engineer podcast, Sam explains his thinking on this, and he’s certainly well placed to do so; he was in the room when the term “microservices” was coined. We discuss what teams get wrong when adopting microservices, why independent deployment matters, and how microservices can help teams work more autonomously. We also delve into his new book, ‘ Building Resilient Distributed Systems ’, and Sam explains his three rules for distributed systems, why observability is essential, and also why it’s vital to take business context into account when deciding whether to fail open or fail closed on errors. We also explore how AI is changing software development, from specs versus code as a source of truth to cognitive debt and cognitive surrender. Sam shares how modular architecture can help teams experiment with AI while maintaining understanding of the systems being built. Timestamps 00:00 Intro 03:16 Sam’s path into tech 09:32 Thoughtworks 20:55 The rise of microservices 33:37 Are specs becoming more important than code? 45:22 Building Resilient Distributed Systems (Sam’s new book) 52:35 Three rules of distributed systems 56:16 Observability 1:02:20 Resilience tradeoffs 1:07:54 Idempotency 1:15:58 Thundering herds 1:21:03 Business context and resilience decisions 1:25:51 Resilience engineering: four concepts 1:32:42 AI and resilience 1:36:26 AI’s limitations and where to use it 1:40:06 Cognitive debt and cognitive surrender 1:45:02 Modular architecture and AI software factories 1:51:53 Resources for learning software architecture 1:55:30 Where to find Sam — The Pragmatic Engineer deepdives relevant for this episode: • Scaling Uber with Thuan Pham (Uber’s first CTO) • What is good software architecture at Netflix? • The past and future of modern backend practices • What is reliability engineering, and the history of SRE • How to debug large, distributed systems: Antithesis • Designing Data-intensive Applications with Martin Kleppmann • Building Bluesky: a Distributed Social Network — Production and marketing by ⁠⁠⁠⁠⁠⁠⁠⁠ https://penname.co/⁠⁠⁠⁠⁠⁠⁠⁠ . For inquiries about sponsoring the podcast, email podcast@pragmaticengineer.com. Get full access to The Pragmatic Engineer at newsletter.pragmaticengineer.com/subscribe