Christian Prior-Mamulyan’s Post

I hid an Easter Egg in our tooling… It’s fast. In case you haven't heard, there is a new kid on the block doing fast type checking: ty https://docs.astral.sh/ty/ ty is a new type checker from the team behind ruff (the linter that already replaced flake8 and black for us). It's written in Rust. Same idea: take a critical Python dev tool and make it instant. Our Python codebase runs mypy on every commit and every PR. It works, but sometimes you see that 2-3 seconds wait that even on a mid-size project, it adds noticeable seconds to every pre-commit hook and CI run. Multiply that by every developer, every push, every day. What we did: 1. Tested removing the Pydantic mypy plugin, zero new errors. It wasn't catching anything our type annotations didn't already cover. 2. Ran ty alongside mypy to compare output. 99 initial errors, all from third-party library stub gaps (SQLAlchemy, pyarrow), not real bugs. 3. Added per-module overrides in pyproject.toml to suppress the stub noise, same thing we were doing with mypy's # type: ignore comments. 4. Swapped mypy for ty in pre-commit, CI, and our justfile. Removed mypy entirely. Result: Type checking went from "look out the window" to "already done." Same coverage, same confidence, faster feedback loop. Should you migrate today? If you rely heavily on mypy plugins (Pydantic), test without them first. If your codebase passes clean, you're good to go. If not, wait for ty's plugin ecosystem to mature. You could argue that ty is still early but is moving incredibly fast. For well-typed codebases, it's already a drop-in improvement. Migration inspired by https://lnkd.in/eu5iMfS2

pyLoad is a free and open-source download manager written in Python. The fix for CVE-2026-33509 added an ADMIN_ONLY_OPTIONS set to block non-admin users from modifying security-critical config options. The storage_folder option is not in this set and passes the existing path restriction because the Flask session directory is outside both PKGDIR and userdir. A user with SETTINGS and ADD permissions can redirect downloads to the Flask filesystem session store, plant a malicious pickle payload as a predictable session file, and trigger arbitrary code execution when any HTTP request arrives with the corresponding session cookie. This vulnerability is fixed with commit c4cf995a2803bdbe388addfc2b0f323277efc0e1.

The Model Context Protocol, or MCP, has changed how LLMs connect with data and tools. It can expose data as resources, provide actions through tools, and define prompts that guide how the model interacts with data or users. In this guide, Manish teaches you how to build your own MCP server using the FastMCP Python framework. https://lnkd.in/gCwmUgr5

VSCode workspace is a game changer! If you're writing Python codes for different versions (2.* and 3.*), then you should try the workspace in VSCode. Basically with workspace, you can define/set which CPython version to use when you click the play/run button in VSCode. This is very useful in cases where you might be trying out a logic in Python 2 and also on Python 3, or when you're migrating either upwards (from 2 to 3) or downwards (from 3 to 2), and since it's on the same IDE, the experience is really enjoyable. This also works on the same major version, so maybe you have Python 2.2 and 2.7, or 3.10 and 3.13; and it's not limited to just 2, you can have more. First time I tried it, had me smiling :) cause I work on different versions and it's not fun going to console and manually typing which python version to run on which folder --- (side note: python launcher is a great tool, but having an IDE that can support multiple versions seamlessly is just another level of ease). I really liked it, try it and see for yourself ;) #vscode #workspace #dcm #python

LeetCode Problem 217: Contains Duplicate (Python) I’m following the beginner LeetCode roadmap, and today I learned and completed problem #217 — Contains Duplicate. I used a set to achieve O(n) time complexity, with O(1) average-time lookups. The idea is simple: iterate through the list and add each number to a set. If you ever see a number that’s already in the set, you’ve found a duplicate, so you can stop immediately and return True. For example, if the list is [1, 3, 5, 3, 1], the set will grow to {1, 3, 5}. When you reach the 4th element (3), it’s already in the set, so the algorithm stops and returns True. Some of you might think it should keep going because there are two duplicates. That’s true, but for this problem you only need to know whether any duplicate exists, so stopping at the first one is enough.

No more duplicate dependencies in pyproject.toml! Pixi Python packages can now set `ignore-pypi-mapping = false` to automatically convert `pyproject.toml` dependencies into conda package requirements. The goal is no configuration, this is a step in that direction! Find the documentation here: https://lnkd.in/di2aQiyj

Built something that could save an engineer hours. Feed it any Python function → it uses Claude to automatically generate a full pytest test suite: happy path, edge cases, error handling, security. 🔗 https://lnkd.in/gwg7RZ65

I replaced my usual setup (pip + virtualenv + pip-tools) with uv — and the difference was honestly surprising. ⚡ Faster installs ⚡ Simpler workflow ⚡ One tool instead of three I wrote a quick blog breaking it down: What uv actually does How it compares to pip Whether it’s worth switching If you're working with Python, this might save you a lot of time 👇 https://lnkd.in/d9Y4mcUP

A Python package with 35M monthly downloads was compromised today. Malicious code. Credential exfiltration. Self-replication. The package was LiteLLM — the exact abstraction layer sitting between your app and every LLM provider you use. This is why your abstraction layer choice is an architectural decision, not a library preference. New article in first comment👇

Claude Agent SDK tracing in LangSmith just got an upgrade. Now you can trace: → Subagents → Child runs inside MCP tools → Cost tracking + more Update to the latest Python SDK to try it out. Docs: https://lnkd.in/gTaNkWMa