AI, software engineering, and product building — practical insights from Marcin Kołodziej on building things that work.https://markolo.dev/en-usmarcin@markolo.dev (Marcin Kołodziej)https://markolo.dev/posts/building-with-llms-practical-guide/https://markolo.dev/posts/building-with-llms-practical-guide/A hands-on guide to integrating large language models into real applications — from API selection to prompt design to production pitfalls.Sat, 15 Mar 2025 00:00:00 GMTaiengineeringhttps://markolo.dev/posts/rag-systems-beyond-basics/https://markolo.dev/posts/rag-systems-beyond-basics/Go beyond simple retrieval-augmented generation — learn about chunking strategies, reranking, and evaluation metrics that make RAG systems actually useful.Wed, 12 Mar 2025 00:00:00 GMTaiengineeringhttps://markolo.dev/posts/shipping-fast-without-breaking-things/https://markolo.dev/posts/shipping-fast-without-breaking-things/How to maintain velocity in a startup without accumulating catastrophic technical debt — practical strategies from the trenches.Mon, 10 Mar 2025 00:00:00 GMTengineeringproductshttps://markolo.dev/posts/prompt-engineering-is-software-engineering/https://markolo.dev/posts/prompt-engineering-is-software-engineering/Stop treating prompts as throwaway text. Version them, test them, iterate on them — the same discipline you apply to code applies to prompts.Sat, 08 Mar 2025 00:00:00 GMTaiengineeringhttps://markolo.dev/posts/building-mvp-that-matters/https://markolo.dev/posts/building-mvp-that-matters/Most MVPs fail not because of technology but because they solve problems nobody has. Here's how to build one that validates real demand.Wed, 05 Mar 2025 00:00:00 GMTproductsengineeringhttps://markolo.dev/posts/vector-databases-explained/https://markolo.dev/posts/vector-databases-explained/What vector databases actually do, when you need one, and how they differ from traditional databases — explained without the hype.Sat, 01 Mar 2025 00:00:00 GMTaiengineeringhttps://markolo.dev/posts/technical-debt-as-product-decision/https://markolo.dev/posts/technical-debt-as-product-decision/Technical debt isn't always bad — it's a tool. The key is knowing when to take it on and when to pay it down, treated as a product decision.Fri, 28 Feb 2025 00:00:00 GMTengineeringproductshttps://markolo.dev/posts/fine-tuning-vs-rag-when-to-use-what/https://markolo.dev/posts/fine-tuning-vs-rag-when-to-use-what/The most common question in AI engineering doesn't have a simple answer. Here's a framework for deciding between fine-tuning and RAG.Tue, 25 Feb 2025 00:00:00 GMTaiengineeringhttps://markolo.dev/posts/validating-ideas-before-writing-code/https://markolo.dev/posts/validating-ideas-before-writing-code/The best code is code you never write. Learn frameworks for validating product ideas before investing engineering time.Thu, 20 Feb 2025 00:00:00 GMTproductsengineeringhttps://markolo.dev/posts/ai-agents-architecture-patterns/https://markolo.dev/posts/ai-agents-architecture-patterns/From simple chains to autonomous agents — a practical guide to the architecture patterns behind AI agent systems that actually work in production.Tue, 18 Feb 2025 00:00:00 GMTaiengineeringhttps://markolo.dev/posts/building-for-one-user-first/https://markolo.dev/posts/building-for-one-user-first/The counterintuitive path to products that scale: start by building something one person loves, not something many people like.Sat, 15 Feb 2025 00:00:00 GMTproductshttps://markolo.dev/posts/evals-the-missing-piece-in-ai-engineering/https://markolo.dev/posts/evals-the-missing-piece-in-ai-engineering/If you're not evaluating your AI outputs systematically, you're flying blind. Here's how to build an evaluation pipeline that catches regressions.Mon, 10 Feb 2025 00:00:00 GMTaiengineeringhttps://markolo.dev/posts/from-side-project-to-product/https://markolo.dev/posts/from-side-project-to-product/The journey from weekend hack to something people pay for — lessons learned, mistakes made, and the mindset shift that makes it possible.Wed, 05 Feb 2025 00:00:00 GMTproductsengineering