Vladimír Zdražil Posts

In many stateful systems, API failures aren’t caused by missing endpoints, incorrect schemas, or misinterpretations.

Updates 2026-08-27 Since writing this, harness engineering has become a clearer part of working with coding agents.

When you’re working on a project for a long time, you might start to believe that a lot of complexity is needed when it really isn’t.

TLDR Two common ways to represent absence of a value in TypeScript are A | null and Option<A>.

Updates 2023-05-28 Added TypeScript example.

Introduction Tracking down bugs in your code is often frustrating.

TLDR Object.keys() doesn’t return (keyof T)[] in TypeScript because objects can have additional properties at runtime, leading to potential issues.

TLDR AHA (Avoid Hasty Abstractions) principle advises preferring duplication over the wrong abstraction, optimizing for change first, and waiting for necessary abstractions to emerge.

List of links, articles, and other resources you might find interesting from the past few weeks.

Updates 2022-11-13 Added git repl section. 2023-05-07 This article has been split into multiple posts for easier reading and updating.

List of links, articles, and other resources you might find interesting from the past few weeks.

Visual Studio Code already supports searching across all the project files.