Stackblitz

Eric Simons and his co-founder came to Silicon Valley in 2012 and had the good fortune of meeting Evan Wallace and Dillon Field in Figma's early days. They witnessed Figma's bold bet on WebGL and browser-based deep technology to build a design tool from scratch. By 2016-2017, they spotted a similar opportunity: WebAssembly, shared memory, and service workers had landed in browsers, making it theoretically possible to build an operating system in WebAssembly that could run Node.js and the full web development toolchain in the browser. This would eliminate painful developer environment setup and solve the scaling problem that plagued cloud-based IDEs.

Stackblitz spent seven years building WebContainer, the core technology that enables running a full Linux-based OS inside the browser at near-native speed (booting in ~100ms). The founding team of 5-7 people bootstrapped the company, barely spending the modest funding they raised, keeping burn low and maintaining agency. The technology worked beautifully, but the team struggled to find a compelling product use case. Developers loved it, but nobody was paying for it. The company was on the verge of shutting down in late 2023.

Then the AI boom arrived. They realized their 7-year-old WebContainer technology was perfectly suited for AI-powered code generation—it enabled real-time, reliable execution of AI-generated code directly in the browser, with zero latency and no server costs. They built Bolt, an AI code agent that could generate full-stack web and mobile apps from text prompts, in just 90 days.

On launch day (October 2023), Eric tweeted about Bolt. The response was extraordinary: $60K ARR on day one, $80K on day two. The product had no mobile responsive view, no proper chat UI, and was missing basic features—but users loved it anyway. Within the first two months, they hit $20M ARR with 3 million registered users added. By month four/five, they had crossed $40M ARR with ~1M monthly active users.

The core insight: WebContainer solved the server scaling problem that every other AI code generation tool faced. Competitors spun up cloud VMs for each user, which was expensive, slow, and didn't scale. Bolt ran everything locally on the user's device using their CPU, making it fast, reliable, and permissively free-tiered. This technological advantage compounded every aspect of the product experience.

Initially they charged $9/month (their only plan for 7 years). Users burned through $9 in 48 hours and begged to pay more. Within a week, they redesigned pricing to allow higher-tier purchases based on inference usage. This insight—that users saw genuine ROI and would willingly pay more—became industry standard, copied by Cursor and others.

The team faced immediate scaling crises: payment processing, GPU shortages (Anthropic's CEO emailed that they'd run out of capacity), server melting, missing product features, and overwhelming support demand. With only 15-20 people and their chief of staff doing 95% customer support, they triaged ruthlessly while investing in high-impact capabilities like native mobile app support (via Expo partnership), which became their biggest launch ever.

Stackblitz maintains a lean, high-trust team of core members who've worked together 5+ years. They meet every day on all-hands calls, keep PRDs light, and use Figma and Bolt itself for design/prototyping. They use Linear for roadmatics and Notion for documentation. Their forecast for the year is $100M ARR. By most measures, this is the fastest-growing product in startup history—and most of the world still doesn't know it exists.