KEY TAKEAWAYS
- ✓Timing matters enormously. Tony caught the ChatGPT wave at exactly the right moment with exactly the right product.
- ✓Selling a good-but-not-great business to fund your next one is a valid strategy. The $128K from Black Magic gave Tony runway.
- ✓Build in public creates distribution before you even have a product. Tony's Twitter following was his launch platform.
Hello! Who are you and what are you working on?
Tony Dinh's indie hacker journey began the way many do: with a layoff. In 2021, he was working as a software engineer at a tech company when he was let go. Instead of immediately job hunting, he decided to try building his own products. He had some savings, a solid technical background, and a growing interest in the indie hacker movement he'd been following on Twitter.
His first notable product was Black Magic, a Twitter analytics and CRM tool. Tony built it as a solo developer, launching it on Product Hunt and growing it through his own Twitter presence. The tool helped power users manage their Twitter engagement more effectively, tracking followers, managing DMs, and scheduling content. Black Magic grew steadily to around $14,000 in monthly recurring revenue, which was enough to support Tony's lifestyle in Vietnam where the cost of living is relatively low.
Tony became known in indie hacker circles for his transparency. He posted monthly revenue updates, shared technical decisions, and openly discussed the challenges of building a solo SaaS. His Twitter following grew to tens of thousands of people who were genuinely invested in his journey. This audience would become incredibly valuable when he launched his next product.
In early 2023, Twitter announced major changes to its API pricing that would have significantly increased Black Magic's operating costs. Rather than try to adapt, Tony made the pragmatic decision to sell. He found a buyer through his network and sold Black Magic for $128,000. At the time, the business was generating about $14K in monthly recurring revenue, or roughly $168K in annual run rate. The sale price of $128K represented roughly a 9x multiple on monthly revenue, which Tony considered fair for a business with a suddenly uncertain future.
The sale closed in April 2023, and Tony barely paused before starting his next project. ChatGPT had launched a few months earlier and was taking the world by storm. Tony noticed that while the ChatGPT web interface was functional, it lacked features that power users wanted: the ability to use your own API key to save money, better conversation organization, custom prompts, and a cleaner interface. On March 5, 2023, he finished the first version of TypingMind and shared it on Twitter.
The response was immediate and overwhelming. Within the first day, Tony had his first paying customers. Within 11 days, he had made $22,000 in revenue. The product clearly hit a nerve. People were spending significant money on ChatGPT Plus subscriptions ($20 per month) when they could use their own OpenAI API key through TypingMind and often pay less while getting a better user experience.
TypingMind's business model was elegant in its simplicity. Users paid a one-time license fee (starting at $39) to use the software, and then paid OpenAI directly for API usage. Tony had no ongoing API costs, no servers to manage for the AI processing, and no complex infrastructure. The product was essentially a beautifully designed frontend for the OpenAI API with added features like prompt libraries, conversation search, and plugins.
Growth was explosive through 2023. Tony leveraged his existing Twitter audience, launched on Product Hunt multiple times with different feature updates, and benefited from the massive wave of interest in AI tools. TypingMind was featured in countless "best AI tools" lists and roundups, driving organic traffic. By mid-2023, monthly revenue had crossed $50,000.
Tony also added a team/enterprise version called TypingMind Custom, which allowed companies to deploy their own instance of TypingMind with custom branding and centralized billing. This B2B angle opened up a new revenue stream with higher average order values. Companies were willing to pay significantly more for a managed solution they could deploy to their entire team.
The competitive landscape intensified as dozens of ChatGPT wrappers launched throughout 2023 and 2024. But Tony had several advantages: he was first, he shipped updates constantly (sometimes daily), he had a loyal community of early adopters, and his product genuinely worked well. While many competitors raised VC money and hired teams, Tony stayed solo. His costs remained minimal since he lived in Vietnam, had no employees, and the product architecture meant he didn't need expensive infrastructure.
By 2024, TypingMind had crossed $137,000 in monthly revenue, putting it on pace for over $1.6 million per year. Tony continued to build in public, sharing revenue milestones and product updates on Twitter. He became one of the most visible examples of a solo founder riding the AI wave to significant revenue.
Tony's biggest mistake, by his own account, was holding onto Black Magic for too long before selling. He knew the Twitter API changes were coming and could have started negotiating a sale earlier, potentially getting a better price. But the attachment founders feel to their products, even when the math says to move on, is real. The experience taught him to be more emotionally detached from his businesses and to optimize for outcomes rather than sentiment.
The broader lesson from Tony's story is about positioning yourself to catch waves. He didn't predict that ChatGPT would transform the tech industry. But by building in public, growing an audience, and developing the skills to ship products quickly, he was ready when the opportunity appeared. The $128K from selling Black Magic gave him financial runway, and his Twitter following of tens of thousands gave him a built-in launch platform. When TypingMind was ready, Tony didn't need to figure out distribution because he already had it.
Tony still lives in Vietnam, works from home or cafes, and runs everything solo. He occasionally hires freelancers for specific design or development tasks, but the core product development, marketing, customer support, and business operations are all him. He's proof that a solo developer in a low-cost-of-living country, armed with the right skills and timing, can build a business that generates more revenue than most funded startups.