http://blog.dwornikowski.com/tags/engineering/ Recent content in Engineering on Darek's Blog http://blog.dwornikowski.com/openg.png http://blog.dwornikowski.com/openg.png Hugo -- 0.147.2 en-us Sat, 04 Jul 2026 10:00:00 +0200 http://blog.dwornikowski.com/posts/how-mcp-works/ Sat, 04 Jul 2026 10:00:00 +0200 http://blog.dwornikowski.com/posts/how-mcp-works/ A ground-up explainer of the Model Context Protocol: the host-client-server model, the primitives servers and clients expose to each other (tools, resources, prompts, sampling, elicitation), the transports, and the protocol's evolution from the 2024 launch to the 2026 release candidate. http://blog.dwornikowski.com/posts/prove-it-dual-testing/ Tue, 09 Jun 2026 09:00:00 +0200 http://blog.dwornikowski.com/posts/prove-it-dual-testing/ A small prompt habit that changes how a coding agent verifies its own work: stop asking for passing tests, ask it to prove the feature works — once locally against a real Tilt stack with no mocks, then again on staging against real data and integrations. http://blog.dwornikowski.com/posts/local-model-llm-classifier/ Thu, 07 May 2026 12:00:00 +0200 http://blog.dwornikowski.com/posts/local-model-llm-classifier/ A follow-up to my LLM cost-optimization post: how I replaced ~55% of the remaining LLM calls in a product classifier with a small local model trained on the LLM's own labels — and why the local model ended up more accurate than the labels it learned from. http://blog.dwornikowski.com/posts/cutting-llm-costs-token-optimization/ Fri, 24 Apr 2026 12:00:00 +0200 http://blog.dwornikowski.com/posts/cutting-llm-costs-token-optimization/ A walkthrough of how I cut an LLM-based product classifier's token usage by ~92% through compression, two-stage prompting, exact-match lookups, similarity caching, and batching.