Notes from the people who build with open source

Benchmarks, systems deep dives, and hard-won lessons from OpenTeams engineers.

Your `pip install` Could Have Been Hijacked. Here's How It Got Fixed.

The eMudhra security incident left Python trusting a key that was the number 4. See how maintainers patched pip, certifi and conda-forge.

Daina Bouquin

Senior Developer Advocate at OpenTeams · Oct 30, 2026 · 7 min read

Python Tooling

What's New in Polars 2.0: Streaming by Default and Stricter Types

Khuyen Tran

· Oct 11, 2026

AI Engineering

How to Find Bugs in Your LLM Eval with Claude Code's build-eval

Khuyen Tran

· Oct 6, 2026

AI Engineering

PyTorch Year in Review: OpenTeams' Contributions in 2026

Andrew James

· Oct 6, 2026

Infrastructure

Bare-Metal Rocky Linux Image Mode with Artifact Keeper

Brandon Geraci

· Oct 6, 2026

Latest articles

AI Engineering

Reliable Visual Regression Testing for Humans and Coding Agents

See how JupyterLab made visual regression testing reproducible on Linux machines, cut CI from 55 to 15 minutes and let contributors update snapshots.

Michał Krassowski

Oct 6, 2026 · 15 min read

AI Engineering

Your AI Agent Ignored `AGENTS.md`. Your Linter Won't Let It.

Use lint rules for AI agents to enforce project conventions. Custom ESLint rules like @jupyter/eslint-plugin give agents clear errors they can fix on their own.

Darshan Paudyal

Oct 1, 2026 · 6 min read

AI Engineering

Where Does Jev Fit in a Software Supply Chain? We Benchmarked It Against the Open Alternatives

We benchmarked TypeSafe's Jev, Laya, CLM-8B and Claude Haiku on five package-curation triage tasks. A fine-tuned 421M model matched Jev at a tenth of the latency.

Brandon Geraci

Sep 29, 2026 · 7 min read

AI Engineering

Awesome Jupyter AI: A Map of 100+ Jupyter Extensions for AI

Find the right Jupyter AI extension: a curated map of 100+ chat panels, inline completers, agent bridges and MCP servers for JupyterLab and Notebook 7.

Michał Krassowski

Sep 25, 2026 · 7 min read

LLMs & Inference

MiniCPM5-2B quantization report

MiniCPM5-2B quantization report: the best GGUF weights and K/V cache quants on llama.cpp and BeeLlama.cpp, squeezing a SOTA model into 3 GiB RAM.

Guido Imperiale

Sep 22, 2026 · 5 min read

AI Engineering

I Asked LLMs to Review Another LLM. They Still Got It Wrong

I tested LLM reviewer models on meeting summaries to see when they catch hallucinations, when they delete true claims, and how to choose one.

Khuyen Tran

Sep 17, 2026 · 7 min read

LLMs & Inference

LLMs: Intelligence vs. cost

LLM intelligence vs cost: logarithmic scales in plots hide the cost chasm between frontier and cheap models; actual OpenRouter prices alter the Pareto frontier.

Guido Imperiale

Sep 1, 2026 · 6 min read

Python Tooling

pixi on UBI-micro: A Safer, Smaller Multi-Stage Container Build

How a UBI-micro multi-stage build shrinks a pixi container's attack surface and CVE count, with side-by-side Trivy and Grype scans on UBI full, minimal, and micro.

Brandon Geraci

Jul 24, 2026 · 12 min read

AI Engineering

The Best Code Review Says Less

Far too many AI code review comments are noise. Pair a human editor with AI, surface only the findings that matter, and encode that discipline in a reusable skill.

Johnny Bouder

Jul 24, 2026 · 5 min read

AI Engineering

You Don't Drive AI. You Ride It.

AI is stochastic, not deterministic. You don't drive it, you ride it: make documents the memory, use the variation to prototype, and verify every public claim.

Amelia (Mia) Thurdekoos

Jul 9, 2026 · 11 min read

AI Engineering

Who Is Your Code's Audience? An Engineering Team Talks AI-Written Code

Learn why your code's audience decides how much readability matters, as an engineering team debates AI-written code, review, and accountability.

Amelia (Mia) Thurdekoos

Jul 9, 2026 · 9 min read

Python Tooling

The `tp_as_number` Slot and Binary Operation Dispatch in CPython

How CPython dispatches binary operations via tp_as_number slots, and how TorchDynamo mirrors that model to improve correctness and reduce ad-hoc special cases.

Guilherme Leobas

Jun 22, 2026 · 6 min read

AI Engineering

PDF Table Extraction: Docling vs Marker vs LlamaParse Compared

Compare three Python tools for PDF table extraction: Docling, Marker, and LlamaParse. Learn which handles merged cells and multi-level headers best.

Khuyen Tran

May 19, 2026 · 10 min read

LLMs & Inference

Sandboxing Code Mode for Local LLM Agents

Code mode can make local LLM agents more practical, but executing model-written code brings sandboxing back into the architecture.

Nick Byrne & Khuyen Tran

May 4, 2026 · 4 min read

AI Engineering

Plugin Playground AI Integration for Faster Plugin Prototyping

Learn how we integrated AI into Plugin Playground to help you create, edit, test, package, and share JupyterLab plugins faster in JupyterLite and Binder.

Anuj Kumar Singh

Apr 24, 2026 · 5 min read

AI Engineering

Slow Down — Simple Lessons for Guiding AI and Shipping Better Code

Practical lessons for shipping better code, staying in control, keeping your skills sharp, and getting real value from AI coding tools without losing yourself in the hype.

Johnny Bouder

Apr 23, 2026 · 3 min read