Writing

Time series · Honest baselines

I benchmarked five forecasters against “tomorrow = today”. It won.

Five models, twenty stocks, sixteen years of real market data — and the one-line baseline came first. Why that is the right answer, and what it takes to trust it.

3 min read · Forecasting Baselines

Analytics engineering · Data quality

What 541,909 real invoices taught me about honest data pipelines

A quarter of the rows had no customer id. What you do with those rows is the project — not the SQL, and not the model.

4 min read · SMB Growth Intelligence

Reinforcement learning · Sim-to-real

Teaching an AI to play a game that kills you instantly

One button, instant death, and a game that runs at 60 fps. The interesting problem was not the agent — it was refusing to train inside the thing I was training for.

4 min read · Geometry Dash RL