[MM’s] Engineering Weekly #22 — August 25th, 2025
System design tips, Java updates (JDK 25/26, DDD), Kafka best practices, AI coding benchmarks and software engineering culture trends.
Your weekly dose of modern engineering. A mix of deep dives into system design, Java updates, LLM benchmarks, and cultural shifts in engineering. From Spotify design interviews to Stripe’s 1,145 PRs per day, this week brings lessons in scaling, coding smarter, and understanding where our industry is headed.
Architecture & System Design
- System Design Interview Question: Design Spotify: “This is a system design interview question, which is to design Spotify.”
- Everything I know about good system design: “I see a lot of bad system design advice. One classic is the LinkedIn-optimized ‘bet you never heard of queues’ style of post.”
- Do things that don’t scale, and then don’t scale: “There’s an old startup mantra — probably from the early Airbnb or Y Combinator days — that goes: ‘Do things that don’t scale.’”
Java & Development Trends
- 21 ChatGPT Hacks Every Java Developer Should Be Using Right Now: “This isn’t just AI hype — this is how I code faster, debug better, and save my sanity.”
- Domain-Driven Design in Java: A Practical Guide: “DDD is an approach to building robust business applications by focusing on the core domain.”
- New Java Benchmark for Coding LLMs puts GPT-5 at the top: “The Brokk Power Ranking is a new open-source coding benchmark, featuring 93 tasks from large, real-world codebases.”
- JDK 25 and JDK 26: What We Know So Far: “JDK 25, the next Long-Term Support (LTS) release since JDK 21, has reached its second release candidate with a final set of 18 new features.”
Tools, Frameworks & Engineering Practices
- Top 10 Kafka Anti-Patterns That Are Killing Your Microservices Performance: “Avoid These 10 Common Kafka Mistakes in Spring Boot Applications.”
- How Stripe Ships 1,145 Pull Requests Per Day: “And How Your Team Can Too.”
- Code Review Can Be Better: “A lot of people are unsatisfied with GitHub’s code review process.”
- The future of large files in Git is Git: “If Git had a nemesis, it’d be large files.”
AI & Software Engineering
- Why LLMs Can’t Really Build Software: “From the Zed Blog: Writing code is only one part of effective software engineering.”
- Claude Sonnet 4 Expands to 1 Million Token Context Window: “Anthropic has upgraded Claude Sonnet 4 to support a context length of up to 1 million tokens.”
Industry & Culture
- Inside Netflix’s $1 Billion Algorithm: “How Recommendations Predict Your Next Binge.”
- Developers, Reinvented: “A transformation in the making.”
- New trend: extreme hours at AI startups: “Pulling 80+ hour work weeks — including weekends — is becoming the norm across AI startups.”
- We replaced passwords with something worse: “Too many services have been using the following login method…”
- Typed languages are better suited for vibecoding: “It seems that typed, compiled, etc. languages are better suited for vibecoding, because of the safety guarantees.”
Originally posted on marconak-matej.medium.com.