Oh That Data Girl

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Olga Braginskaya

Week 7: Shipping While Tired (or: Still Alive, Surprisingly)

This week was quiet. Not because nothing is happening, but because after six weeks of pushing, adding platforms, adding metrics, debugging queues and arguing with reality, we’re tired. The kind of tired where you stop dreaming about new features and start dreaming about “everything still works tomorrow”. And honestly

Build in Public: Week 6. Trying to Add More Social Platforms

Last week was about observability. We added metrics and dashboards so we could see what the system was actually doing instead of relying on intuition. So this week wasn’t about inventing something new from scratch. It was about answering a very practical question: can we extend the same idea

Build in Public: Week 5. The Week We Finally Measured Things Instead of Just Hoping for the Best

Last week I ended with a dramatic cliffhanger: “We need metrics!” And then immediately regretted it, because “metrics” is one of those words that sounds simple until you realize you now have to measure things сonsistently and over time. And then look at the numbers even when you don’t

Build in Public: Week 4. The Messy Middle Of Building An AI Agent

This was supposed to be the week of a polished demo video and a clean “here’s how you use our API” walkthrough. Instead, it turned into the week of staring at half-finished pieces, poking at logs and wondering why we voluntarily chose Instagram as our first supported social network.

Build in Public: Week 3. First Survive Discovery, Then Enjoy Analysis

Last week I noticed something annoying: the engagement on my Week 1 and Week 2 posts dropped, even though the content was objectively good. So I asked Perplexity when developers actually read dev.to and the answer was basically: please stop posting on Saturdays. No one is there. From there,

Build in Public: Week 2. How Do People Even Find Influencers?

If you remember from the last update, we had our first real conflict: Node.js vs Python. Well, democracy has spoken. My "many" LinkedIn followers voted and the winner is Node.js. So this week we’re continuing with one backend, one direction and slightly fewer arguments. But

Build in Public: Week 1

The first week wasn’t particularly shiny. We mostly tried to move from our old n8n setup to a normal backend and figure out what “normal” even means for us. Somewhere along the way we also had our first team conflict and our first real issue with Bright Data, so

Build in Public: Day Zero

A few weeks ago we built an agent called WYKRA for the Real-Time AI Agents challenge powered by Bright Data and n8n. It was a small experiment that could accept a natural-language query like “I run a small bakery in Barcelona, find influencers who talk about bread here” and return

Three Formats Walk into a Lakehouse: Iceberg, Delta and Hudi in a Local Setup You Can Run on Your Laptop

I still remember building an entire bookkeeping system in FoxPro for my university coursework back in 2007. Planning every table structure upfront, carefully designing indexes because adding them later meant locking everything up for a reindex, managing backups manually, worrying about file corruption. Every schema change was a small crisis.

When Small Parquet Files Become a Big Problem (and How I Ended Up Writing a Compactor in PyArrow)

It all began with a fairly normal data pipeline. Events were coming in through Kafka, landing in AWS S3 as Parquet files after going through some lightweight microbatch processing. It looked clean at first glance. Efficient. Predictable. But one day I opened one of the hourly folders and saw the