Built a global stock-market platform for web and iOS, plus an autonomous AI content engine that runs its X account

The global market, ranked live: roughly 5,700 companies across the US, Asia, Canada, the UK, and Europe, every one normalized to USD, with a full research suite around the rankings.

Built solo end to end, shipping on the web and as a free iOS app. And it markets itself: an autonomous engine posts to X five or six times a day, straight from production data.

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Services

Full-StackiOS AppAI AgentsContent AutomationReal-Time Data

Tech Stack

Next.js 15React 19React NativeExpoSkiaDrizzle ORMPostgreSQLBetter AuthClaude APIsatoriCloudflareStripeRailway

Industry

FinTechMarket Data

Year

2026

It posts these itself

An autonomous engine runs the X account: five or six posts a day, copy written by an LLM from production data, a branded card on every post. A validator makes an invented number impossible to publish.

A head-to-head post puts two names side by side on five-year performance, each with its own dither chart
A head-to-head post puts two names side by side on five-year performance, each with its own dither chart
Congressional filings become plain, defamation-safe posts within hours of disclosure
Congressional filings become plain, defamation-safe posts within hours of disclosure
A gainer post carries the day's top movers, US and Chinese listings side by side. The universe is global, so the feed is too
A gainer post carries the day's top movers, US and Chinese listings side by side. The universe is global, so the feed is too
Every post carries a card rendered server-side from live data, like the market heatmap
Every post carries a card rendered server-side from live data, like the market heatmap
Movers cards mix US, European, and Chinese listings in one table
Movers cards mix US, European, and Chinese listings in one table

One chart engine, everywhere

Every chart shares a custom engine with a signature reverse-dither fill: solid at the value line, scattering into pixels below. The same look carries from the web to iOS to every share card.

The dither fill on a live intraday session
The dither fill on a live intraday session
The same treatment across a decade of financials
The same treatment across a decade of financials

The whole market, one product

Roughly 5,700 companies across the US, Asia, Canada, the UK, and Europe, FX-normalized into one live USD ranking, with the research suite built around it.

The live ranking with the day's biggest market-cap moves
The live ranking with the day's biggest market-cap moves
The heatmap, sized by market cap and grouped by sector
The heatmap, sized by market cap and grouped by sector
The screener spans exchanges and native currencies, normalized to USD
The screener spans exchanges and native currencies, normalized to USD
Smart money on every stock: insider and congress activity, with Plus behind the gate
Smart money on every stock: insider and congress activity, with Plus behind the gate

The market in your pocket

A free iOS app built with React Native and Expo in the same monorepo, with updates shipping over the air between store releases.

StockMarketCap image 12
StockMarketCap image 13
StockMarketCap image 14

Engineering notes

Global normalization

Nine markets, each with its own currency and calendar, reconciled into one USD ranking that updates live.

An LLM that cannot invent a number

The model writes prose only. A whitelist owns the numbers, so a hallucinated figure is structurally impossible to publish.

The dither shader

The Canvas chart fill had no iOS equivalent, so it was rebuilt as a Skia fragment shader that matches the web pixel for pixel.

Cacheable pages with a paywall

Stock pages stay static ISR. Entitlements are fetched client-side, so the paywall never touches the cache.

Outcome

A complete product behind a paid tier, live on the web and the App Store, built and operated by one person.

The growth engine posts five or six times a day unattended, every number validated against production data.