00 / Wrocław, Poland

“You can’t do everything.” We’ll see.

Advice from my high school IT teacher, who wanted me to pick one thing and stick with it. So far I've written CI pipelines, AI platforms, a code search engine and .NET frameworks.

C#, Rust, TypeScript, Python.

01 / writing all 11 posts →

LISTEN/NOTIFY performance in PostgreSQL

A NOTIFY in the transaction capped PostgreSQL 18.6 and 19 RC1 at about 3,900 commits per second, with 8 clients or 64. Sending notifications in batches after commit brought 64 clients back to 50,000.

measurement 2026-11-04 · 9 min

A read-only MCP server for TeamCity

29 read-only tools for TeamCity. Paste the link to a failed build, get a root-cause analysis built from the actual log lines and test failures.

build notes 2026-11-02 · 3 min

Designing tools that AI can actually use

The tool description is a big part of the interface. If the model can't tell when to call a tool from its description and schema, quality falls apart.

build notes 2026-06-30 · 7 min

Loading code without the disk: what each OS lets you get away with

memfd, PE loaders, unlink-after-dlopen. Three operating systems, three different definitions of 'in memory'.

build notes 2026-05-12 · 7 min

paker: load encrypted Python packages from memory

Encrypt a Python package tree, ship it over the network, load it from memory. What works, what doesn't.

build notes 2026-05-06 · 2 min

I built a read-only MCP server for Akamai

16 tools for searching CDN properties, browsing EdgeWorker code, querying DNS, and inspecting network lists. All read-only.

build notes 2026-04-29 · 4 min

04 / get in touch

If something here is wrong, or you are working on the same problems, I want to hear from you. Email works best: wojciech.wentland@gmail.com.