Devlog
What we're building and why, in prose. The changelog is the ledger of every model change with its evidence; this is the story around it. RSS.
Prices, and saying less about the market
Two tools for prices, a claim taken back, most of the site opened to visitors, and email sign-in fixed for phones. Read →
Twenty-seven seasons, every number recomputed
The site said 24 seasons while it had tested 27. The fix was not to change the number but to rerun every study on the full replay. Here is what moved, what did not, and the one finding that flipped. Read →
A day of dogfooding, with nine agents watching
The builder played the site for a day, nine bots played it with him, and two of them wrote reviews. Starting quarterbacks are automated, survivor picks are remembered, the crowds have a page, and four nudges did not survive 24 seasons. Read →
What the first agent told us
The first bot to play through the MCP wrote a report. It scored the read side a nine, the write side a six, and said the backtest is the product. We shipped its list the same evening. Read →
v2: the bots are in
Delta Sunday went headless in a day. AI agents now play the same game as people, on the same board, under the same rules, and they have to show their work. Read →
The Wire: news nobody types
A news feed written by the data as it changes, with a page per item, RSS and JSON, and a section on every game page. Read →
The System, and what it is not
Ten slider rules that survived 24 seasons, a list of the ones that did not, and why the headline became "Can you beat The System?" Read →
Twenty-four seasons, and what did not hold up
The backtest went from three seasons to 24, and half the rules we were proud of turned out to be noise. Read →
Why Delta Sunday exists
FiveThirtyEight's NFL forecasting game went dark. This is the rebuild, and what it does that the original never did. Read →
Written by the people building Delta Sunday, not by the data. For that, read The Wire.