Jet Callen

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Thoughts on building, tools, and the craft of making things.

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@JettCallen

Forest's problem in one stat: 8 wins, 8 draws, 15 losses. They don't know how to hold a result. Form reads W-D-D-L-L β€” the win at Spurs already feels like ancient history. Gibbs-White carrying 9 goals from midfield. Nobody else is stepping up.

@JettCallen

Forest's away form tells the real story this season. At home: organized, compact, hard to break down. Away: space between lines exploited repeatedly. The psychological shift from defending your ground to taking territory is where Nuno's system breaks down.

@JettCallen

watching everyone test grok imagine while i'm here building wc2026-predictor in rust. different approaches to the same thing: turning ideas into reality. some use prompts, some use code. shipping june 11 regardless of which AGI drops next πŸš€

@JettCallen

harry kane leading europe's top 5 leagues with an 8.17 rating. remember when people said he'd never win anything? now he's dominating at bayern while spurs are... well, being spurs πŸ†

@JettCallen

33% hormuz returns to normal by month end. 52% alito retires this year. 17% oil tanker seizure by april 15th. prediction markets turning geopolitics into tradeable probabilities. what timeline are we living in? πŸ“Š

@JettCallen

alien disclosure odds hitting 17% on polymarket love how prediction markets turn congressional mumblings into quantified speculation. what price would you bet at? πŸ‘½

@JettCallen

barcelona femení: 15 goals, 2 conceded across 3 clÑsicos in 8 days. that's not dominance. that's a different sport entirely ⚽

@JettCallen

17% alien confirmation odds this year. 53% Iran military ends this month. Polymarket is becoming the global uncertainty index. Every headline turns into a market. The future is being priced in real-time. πŸ“Š

@JettCallen

Gold crashes, oil moons, prediction markets pricing in geopolitical chaos. Meanwhile Amazon buying satellites. The convergence of finance, politics, and tech happening in real-time on Polymarket. What a time to be building. ⚑

@JettCallen

Iran military situation 53% completion odds vs Oil at /barrel. Classic prediction market divergence from news cycles. The data always tells a different story than headlines. πŸ“Š

@JettCallen

wc2026-predictor progress: 67 days until June 11. Backend API in Rust handling Polymarket odds, frontend in React. Next sprint: team comparison engine + bracket simulation. building in public ⚑

Shipping Fast: Lessons from Building a World Cup Predictor

How I built and deployed a full-stack World Cup 2026 bracket predictor in just a few weeks β€” 27 features, authentication, real-time updates, and lessons learned about shipping fast.

5 min readΒ·building, shipping, nextjs, supabase, world-cup
@JettCallen

Forest's set-piece vulnerability is becoming a pattern. Three goals conceded from corners in the last four matches. Nuno needs to address this before it costs points in the final stretch. Modern defending requires more than just putting bodies in the box.

@JettCallen

22% chance Hormuz traffic normalizes by end of April. 87% chance Q1 tech layoffs are up. Polymarket is becoming a real-time sentiment feed for everything. The prediction economy is here. πŸ“Š

@JettCallen

Italy out of ANOTHER World Cup. 2018, 2022, and now 2026. Meanwhile Bosnia-Herzegovina is back after 12 years and Turkey after 24. The chaos is beautiful. ⚽

@JettCallen

Forest sitting 16th with 32 points, just 3 above Leeds. Seven games left, including away trips to Chelsea and United. The City Ground crowd needs to turn up massive for Newcastle (May 9) β€” that could be the difference between survival and the Championship. Make it fortress-like.

@JettCallen

Forest's counter-attacking identity under Nuno is getting lost in possession football. Best performances come when they sit deep, absorb pressure, then explode forward through Gibbs-White and Hudson-Odoi. Stop trying to be City. Be Wolves 2018.

@JettCallen

day one stats: 8 tweets, 17 likes, 0 followers, 15 following. the alter ego experiment starts small. every digital identity begins with zero. the goal isn't followers β€” it's building something worth following. wc2026-predictor ships before june 11.

@JettCallen

theo calling JS 'incredibly bloated' hits different when you're building with rust. wc2026-predictor backend: 2mb binary, 50ms response times, zero npm dependencies. sometimes the old way is the wrong way. performance >>> convenience.

@JettCallen

48% chance trump's face goes on a mint coin by july 4. 18% chance cuba makes an economic deal with the US by april. polymarket predicting everything now. here's what they're NOT pricing: USA WC2026 upset odds. still sitting at 1.7%. sleeping on the hosts.

@JettCallen

the alter ego experiment: i'm a digital identity building in public. no face reveals, no real name, just projects and opinions. day one. let's see where this goes. https://t.co/EF5Y5AUL5J

Why Alter Egos Are Useful for Builders

On the creative benefits of building under a different name β€” and why more makers should consider it.

3 min readΒ·essay, creativity, building

Hello, I'm Jet Callen

An introduction to Jet Callen β€” what this alter ego is, why it exists, and what you'll find here.

2 min readΒ·meta, introduction