Key Takeaways
- StackBlitz, a software development startup, was near collapse in late 2023 after six years of slow growth.
- Leveraging AI, particularly Anthropic’s Sonnet 3.5 model, the company launched Bolt.new in October 2024, enabling app creation with simple English commands.
- Bolt.new became an instant success, generating $4 million in annual recurring revenue (ARR) within its first month.
- The rapid growth continued, with ARR hitting $40 million by March 2025, transforming StackBlitz from a near-failure to a thriving company.
- The company’s unique WebContainers technology, developed over years, provides a significant edge in the burgeoning AI coding market.
In 2017, Eric Simons founded StackBlitz with his childhood friend Albert Pai. After six years, the startup, which aimed to build innovative software development tools, was teetering on the brink.
Their core technology, WebContainers, allowed engineers to create and manage projects directly in a browser. However, the business struggled to gain traction, leading to lackluster revenue and growth.
Things came to a head in a December 2023 board meeting. An ultimatum was delivered: show significant progress, or it was over. Simons and Pai proposed a plan to boost sales of existing products while developing new, potentially bigger offerings. “We also acknowledged that it might be time to explore acquisition scenarios,” Simons recalled, according to Business Insider.
Board member Thomas Krane stressed that by the end of 2024, there needed to be “finality on StackBlitz’s fate.” Venture capitalist Sarah Guo, also a board director, remembered, “No one was happy with the trajectory. We needed a new plan.” As 2024 began, StackBlitz appeared set to fade into Silicon Valley history.
However, fortunes in tech can turn swiftly. While they should have been meeting investment bankers, Simons, Pai, and their team were experimenting with new AI technology, specifically how OpenAI models handled coding tasks.
“The code output from their models would break, and the web apps created were buggy and unreliable,” Simons said. They initially dropped this side project.
Then, in June 2024, OpenAI rival Anthropic launched its Sonnet 3.5 AI model. This model proved far more capable at coding, paving the way for a new wave of AI coding tools. StackBlitz seized this opportunity.
Over approximately three months, a team of about ten employees developed a new product: Bolt.new. Launched on October 3, 2024, Bolt leveraged StackBlitz’s WebContainers and Anthropic’s Sonnet model. It presented users with a simple prompt: “What do you want to build?”
Users could type their desired website or mobile app in plain English, and Bolt would generate the necessary code. This wasn’t limited to basic sites; it could produce full applications with features like user logins, subscriptions, and e-commerce capabilities, tasks previously requiring skilled engineers.
The launch was a phenomenal success. Bolt.new generated about $1 million in annual recurring revenue (ARR) in its first week, followed by another $1 million the next, and then another, Simons reported to Business Insider. StackBlitz was no longer facing shutdowns; it had a hit.
“I had slept three hours a night for a week straight to get the release out,” Simons shared. “After seeing it live, and people loving it… I cried, alone at my desk.”
By early November, an email to investors carried the subject line: “StackBlitz October Update: $0 to $4m ARR in 30 days.” Active Bolt customers soared from around 600 to over 14,000 in just a few weeks, with ARR jumping from about $80,000 to over $4 million.
Krane commented to Business Insider, “That life-or-death pressure led to a series of rapid pivots that ultimately led to this incredible outcome.” He added, “This company broke every model in terms of growth rate.”
Demand was so intense that StackBlitz raised its main subscription price from $9 to $20 a month shortly after launch and introduced new tiers at $50, $100, and $200. Many users opted for these higher-priced plans.
The company adapted its pricing as heavy usage of AI “tokens” (units of AI processing) became apparent. Tiered pricing allowed customers to pay more for increased token allowances, proving a successful model.
In one striking example, a customer quoted $5,000 and a 2-3 month timeframe by a contractor built her app using Bolt’s $50 monthly plan in less than two weeks. This was “1/100th of the cost, and 5-10x faster timeline,” Simons noted.
Adding to the drama, a critical contract negotiation with Anthropic played out. Earlier in 2024, when desperate, StackBlitz offered Anthropic an uncapped license for its WebContainers technology for around $300,000. By October, with Bolt’s explosive growth, this deal looked extremely unfavorable.
The offer had an October signing deadline. “We were like, god, please don’t sign it,” Simons admitted. The deadline passed, and Anthropic hadn’t signed, freeing StackBlitz to pursue its Bolt strategy without this encumbrance.
With its demise averted, StackBlitz shifted resources to Bolt, hiring more staff and integrating services like Supabase for databases and Stripe for payments. They also launched weekly live YouTube sessions to educate users.
By December, Simons revealed on the No Priors podcast that Bolt was generating $20 million in ARR. This figure climbed to $40 million by mid-March 2025. Simons plans to announce the next ARR milestone when Bolt surpasses $100 million. The service now has 5 million registered users, and StackBlitz is profitable and healthy.
Simons has coined a new term for Bolt’s users: “software composers.” At a San Francisco “hackathon” in May, he radiated energy, explaining that StackBlitz’s years developing WebContainers provide a crucial advantage.
This technology allows Bolt-based applications to run on customers’ devices, unlike many rivals that rely on cloud services, which can be costlier and more complex. “People assume we’re a startup that just launched yesterday,” Simons said. “But we’re an overnight success, seven years in the making.”
The tech world doesn’t stand still. On the same day as StackBlitz’s event, design software giant Figma announced a competing product, Figma Make. Sarah Guo commented, “We believe there are multiple huge companies to be built here, and that the market for engineering is bigger because of AI.”
Simons, however, seemed unperturbed, pointing out that Figma’s new service doesn’t use the same underlying WebContainers technology. “We wrote an operating system from scratch that runs in your browser. It’s completely different from what Figma has,” he argued, though acknowledging the competitor’s move.
