Agentic Coding Is Not a Trap: I Answered the Viral HN Post With My Own Production Logs I made the exact mistake that viral post criticizes: I gave an agent an ambiguous task and went to make coffee. Came back 40 minutes later to 23 modified files, three broken tests, and a refactor nobody asked for. I'm not telling this to complain — I'm telling it because that day I started keeping logs of my a
PostgreSQL Query Rewriting Techniques The previous articles in this series covered performance problems you fix by adding indexes, restructuring joins, or tuning memory. This one is about the queries where the plan is "fine" — every node is doing something reasonable — but the query itself is asking the wrong question, producing unnecessarily large intermediate results or forcing the planner dow
This section is the map for the rest of the book. The five stages introduced in the 1.1 chapter overview (parse, analyze/rewrite, plan, portal, execute) are traced here through the actual code: which functions implement each stage, and in what order they get called. The mechanics of each of the five stages are unpacked in later chapters. Here, only the skeleton matters: how a backend starts up, ho
PostgreSQL Internals · Chapter 1 Query Processing Suppose a client sends SELECT * FROM users WHERE id = 1. The path that single line travels before coming back as a result row is longer than you might expect. Inside the PostgreSQL backend, that SQL goes through a five-stage pipeline. Backend entry and dispatch. The backend receives the message from the client and decides which processing path it s
Apache Stateful Functions is one of the quietly powerful frameworks in the Flink ecosystem - durable per-key state, exactly-once messaging, polyglot remote functions, all on top of Apache Flink. It's also been functionally dormant since October 2024, and it doesn't run on Flink 2.x. We needed it on Flink 2.x. So we maintained the continuation: kzmlabs/flink-statefun. This post is the why and the h
SQL is widely known for data querying and manipulation but systems do grow; data becomes larger; processes become repetitive and operations become sensitive. SQL has some features which enables it to be considered a fully fledged programming language. Some of the features which I discuss in this article are procedures, functions and transactions. Each of these concepts serve distinct purposes. Sto
Introduction Placing RDS in a private subnet protects it from unauthorized external access — but it also means you can no longer connect directly from your developer machine. This article walks you through a step-by-step guide to securely connect to a private-subnet RDS (PostgreSQL) instance using AWS Client VPN. Developer PC │ │ UDP 443 (TLS / Mutual Certificate Authentication) ▼ Client
Billing code is the most dangerous place to have subtle bugs. It rarely crashes — it just silently does the wrong thing. Here are two we found and fixed in ClipCrafter, an AI video clip extraction tool. We track how many seconds of video each user processes per day to enforce plan limits. The original increment looked like this: const { data } = await db .from("users") .select("daily_usage_sec