I'm Denis Smetannikov - Senior Engineering Manager & Staff Engineer at billups (US ad-tech, remote). I lead a distributed team of DS/DE engineers and own a multi-region, petabyte-scale Databricks platform: PySpark, Delta Lake, Unity Catalog.
I've been hands-on with LLMs since 2022, as an early beta tester of the first GitHub Copilot versions, and since 2024 applied AI/LLM engineering is my technical center of gravity - RAG with measured evaluation, LangGraph agents, speech recognition, LLM cost engineering, and spec-driven AI-assisted development (Claude Code first, with GPT, DeepSeek, and local models behind a self-hosted LiteLLM gateway). I like decisions backed by numbers - golden sets before "vibes", WER benchmarks before model choices, and cost per request before scale. Read first, prompt second.
Total stars: 
{:name "Denis Smetannikov"
:role ["Senior Engineering Manager" "Staff Engineer"] ; hands-on player-coach
:own {:platform [:databricks :multi-region :petabyte-scale]
:ai [:rag :langgraph :asr :llm-cost-engineering]}
:like ["Python" "Databases" "Spark" "Clojure" "Go" "PHP"
"SICP" `:code-as-data `:infrastructure-as-data
"Factorio" ["QMK" "Vial"]]
:make (->> [:business :idea ::state ::legacy-code]
(filter bad-practices?)
(some enchantments)
(do-it stateless)
(profit! as-money :your @pocket))} ; It just works!Sometimes I build things for my own convenience and share them with the world.
| Project | What it is |
|---|---|
| JBZoo | 25 PHP packages maintained since 2013 - 14M+ installs on Packagist (~128k/month today), 1.5k+ GitHub stars across the ecosystem. Busiest one: Mermaid-PHP (~28k installs/month) |
| CSV Blueprint | Declarative CSV validator - data contracts as YAML schemas, born from real data-platform work |
| GigaAM OpenAI API Server | OpenAI-compatible Russian ASR server: Silero VAD chunking for long audio, Docker-first |
| Ollama to OpenAI | Ollama→OpenAI translation proxy: per-model config, Jinja2 prompt templating, hot-reload |
| OWUI Token&money Usage Display | Open WebUI plugin: token, context, timing and cost per message - 5k+ installs, highlighted in the official community docs |
| Prompt Engineering framework | Production prompt collection (★100+) + the Ultimate Prompt Architect |
| Obsidian: Date manager | Obsidian plugin in the official community catalog |
Thank you SICP
const iter = (list, time, greyMatterAcc)
=> (experiment)
=> (f, ...k)
=> (rtfm)
=> iter(sicp(list, lisp(λ)), time(--x), ++greyMatterAcc);
let youllNeverBeTheSame = iter(hexletCourses, yourTime, aLittleBitOfBrain);