# Leo Vaicer (Alexey Belochenko) — Personal & Engineering Knowledge Base

> Science-first Systems & Data Engineer focused on dynamic systems thinking, high-load pipelines, observability, and software reliability. Architect of DockCV and Math & Physics Lab.

## Core Links & Pages
- [Home Page](https://www.zeelex.me): Overview of projects, articles, positioning, and contact info.
- [Profile & Experience](https://www.zeelex.me/profile): In-depth experience, technical principles, and trajectory.
- [Curriculum Vitae](https://www.zeelex.me/cv): Browser-rendered CV typeset via DockCV engine.
- [Articles Index](https://www.zeelex.me/posts): Complete list of technical essays and reflections.
- [Math & Physics Lab](https://www.zeelex.me/lab): Interactive simulations and explorable technical explanations.
- [DockCV Workbench](https://www.zeelex.me/dockcv): Local-first native desktop résumé workbench built with Rust & GPUI.
- [PyMolt Engine](https://pymolt.zeelex.me): Python runtime tracing & behavioral diff engine for version migrations.
- [Full Markdown Catalog](https://www.zeelex.me/llms-full.txt): Complete full-text dump of all published essays and lab reports for single-request LLM context ingestion.

## Published Technical Articles & Essays
- [Migrating Five Python Services: What It Actually Looks Like](https://www.zeelex.me/posts/pymolt) [EN]: Migrating five Python services across versions is not a version bump — it is a research project. Tools like pyupgrade and LLM agents handle syntax but miss behavioral changes that only surface at runtime. Pandas v1→v2 and Airflow v2→v3 show why testing strategy matters more than tooling.
 (Tags: Python, Migration, Data Pipeline, DevOps, Airflow, Pandas, Technical Debt)
- [Миграция пяти сервисов Python: как это выглядит изнутри](https://www.zeelex.me/posts/pymolt?lang=ru) [RU]: Миграция пяти Python-сервисов через версии — не просто обновление версии, а исследовательский проект. Инструменты вроде pyupgrade и LLM-агенты справляются с синтаксисом, но упускают поведенческие изменения, которые проявляются только в runtime. На примере pandas v1→v2 и Airflow v2→v3 показано, почему стратегия тестирования важнее инструментов.
 (Tags: Python, Migration, Data Pipeline, DevOps, Airflow, Pandas, Technical Debt, Миграция, Техдолг)
- [A Guide to Being Understood or How Speak with People](https://www.zeelex.me/posts/how-to-explain) [EN]: Every professional term is a compressed suitcase—throwing it at someone is like hitting them with a brick. The t-IAR method (Image, Action, Role) turns complex jargon into clear understanding. Simplifying your language is not dumbing down; it is a profound sign of respect.
 (Tags: Communication, Mentorship, Professional Development, Career Path, Self-reflection)
- [Как быть понятым: руководство по общению с людьми](https://www.zeelex.me/posts/how-to-explain?lang=ru) [RU]: Every professional term is a compressed suitcase—throwing it at someone is like hitting them with a brick. The t-IAR method (Image, Action, Role) turns complex jargon into clear understanding. Simplifying your language is not dumbing down; it is a profound sign of respect.
 (Tags: Communication, Mentorship, Professional Development, Career Path, Self-reflection)
- [My Path in Mentorship: From Those Who Guided Me to Those I Guide](https://www.zeelex.me/posts/mentorship) [EN]: This is a short story about how I ended up where I am now. Not about magical mentors who “change your life,” but about ordinary people who once just said the right words and asked the right questions. About how mentorship can be uneven, funny, sometimes strange - and still work, because it makes us a little braver and a little more honest. And about how no technology can replace a human gaze that sees in you something you haven’t yet managed to see yourself.
 (Tags: Mentorship, Personal Growth, Career Path, Learning Journey, Mentors Matter, Self-reflection, Professional Development)
- [Мой путь в менторстве: от тех, кто направлял меня, до тех, кого направляю я](https://www.zeelex.me/posts/mentorship?lang=ru) [RU]: Это короткая история о том, как я вообще выбрался туда, где сейчас стою. Не про волшебных наставников, которые «меняют жизнь», а про обычных людей, которые однажды просто сказали нужные слова и задали правильные вопросы. Про то, как менторство бывает неровным, смешным, иногда странным, но всё равно работает - потому что делает нас чуть смелее и честнее. И о том, что никакие технологии не заменят человеческий взгляд, который видит в тебе то, чего ты сам пока не разглядел.
 (Tags: Mentorship, Personal Growth, Career Path, Learning Journey, Mentors Matter, Self-reflection, Professional Development)
- [Static Systems Are a Myth: Even Your Cache Lives](https://www.zeelex.me/posts/stat-systems) [EN]: Digital systems are not static—they live their own lives. Caches, queues, and the network are in constant flux. Using Redis and Celery as examples, this article demonstrates how a mathematical model helps predict stability limits under load.
 (Tags: System Design, Stability Analysis, Dynamic Systems, Scaling by Design, Cache, Redis, Celery, Data Pipeline)
- [Статических систем не бывает: даже ваш кэш живёт своей жизнью](https://www.zeelex.me/posts/stat-systems?lang=ru) [RU]: Digital systems are not static—they live their own lives. Caches, queues, and the network are in constant flux. Using Redis and Celery as examples, this article demonstrates how a mathematical model helps predict stability limits under load.
 (Tags: System Design, Stability Analysis, Dynamic Systems, Scaling by Design, Cache, Redis, Celery, Data Pipeline)

## Interactive Lab Experiments & Simulations
- [The Damped Harmonic Oscillator](https://www.zeelex.me/lab/harmonic-oscillator): An interactive breakdown of damped oscillatory motion, exploring how resistance forces decay sinusoidal amplitudes over time using secondary-order differential equations. (Tags: kinematics, differential-equations, physics)

## Contact & Social Identity
- GitHub: https://github.com/belochenko
- LinkedIn: https://www.linkedin.com/in/zeelexes/
- Email: mailto:hi@zeelex.me