Latest / The Indie Hacker Podcast with Fexingo: Solo Developers, SaaS Side Projects, and Independent Tech / How a Solo Dev Used Cold Email to Land 50 Beta Users
Transcript
- Lucas: Let me tell you a story about a solo developer who built a productivity SaaS and launched it to crickets. He posted on Hacker News, nothing. Product Hunt, maybe 20 upvotes. He had a great product — genuinely useful — but nobody knew it existed. Luna: That's the classic indie hacker nightmare. You build something amazing, then realise the real work is getting people to actually try it. Lucas: Exactly. So he pivoted to a channel most of us hate hearing about but that actually works if you do it right: cold email. And I don't mean spammy blasts. He sent exactly 200 carefully crafted emails over one week and landed 50 beta users. Luna: Fifty out of two hundred? That's a 25 percent conversion rate, which sounds almost too good to be true. Lucas: It is unusually high, but it happened because he targeted the right people and his product solved a very specific pain point. Let me walk you through exactly what he did, because the method is repeatable. Luna: Alright, I'm taking notes. What was his product? Lucas: It was a time-tracking tool designed specifically for freelance graphic designers. Most time-trackers are built for agencies or general use, so they have features designers don't need and miss features they do — like per-project invoicing with visual previews. He built that. Luna: So niche targeting was key. He knew exactly who his ideal user was. Lucas: Right. And then he built a list. He used Hunter dot io to find email addresses of freelance designers on Dribbble and Behance who had active portfolios but no mention of a time-tracking tool. He filtered for people who posted about 'freelance burnout' or 'billing headaches' on Twitter. Luna: That's smart — he listened to where they complained. So the list was maybe 300 people? Lucas: Actually, he started with 400 and whittled it down to 200 by checking that each person had a real website and was actively freelancing. He didn't want to waste anyone's time. Then he wrote a single email template but personalized the first line for each recipient. Luna: What did the email say? Give me the structure. Lucas: Subject line: 'Quick question about your billing process' — framed as a curiosity, not a pitch. First line: 'Hey, I saw your portfolio — the is beautiful.' Then: 'I'm building a time-tracker that auto-generates invoices with visual previews, because I know freelancers hate manual billing. Would you be open to trying a beta version for free? No strings.' That's it. Short, respectful, and it offers value. Luna: So no 'try our amazing product' or 'we're changing the industry' fluff. Just a direct ask. Lucas: Exactly. And he sent them all within a two-hour window on a Tuesday morning. He used Mailshake to schedule them, but the personalization was manual. He got 37 replies in the first 24 hours — mostly yeses, a few nos with polite feedback. By the end of the week, he had 50 people signed up. Luna: That's incredible. But what about deliverability? Sending 200 cold emails from a personal domain can land you in spam folders fast. Lucas: Great question. He warmed up the domain for two weeks beforehand — sending a few emails a day to known addresses, gradually increasing volume. And he used a separate subdomain — like mail dot hisproduct dot com — so if anything bounced, his main domain stayed clean. He also included a one-click unsubscribe link in every email. Luna: So the infrastructure mattered as much as the copy. I feel like a lot of indie hackers skip that step and then wonder why their emails never land. Lucas: Absolutely. And another thing: he sent a three-email follow-up sequence to non-responders. First follow-up after two days, just a friendly 'hey, wanted to make sure you saw this.' Second after five days, with a testimonial from a beta user. Third after ten days, a final 'we're closing beta soon' — which created scarcity. Luna: That follow-up sequence probably doubled his response rate. Most people give up after one email. Lucas: Exactly. And the key is that each email added value — a testimonial, a new feature mention, a deadline. It wasn't just 'please reply' nagging. That's why people didn't mark it as spam. Luna: I want to talk about whether this works for B2C products. Because his was B2B — targeting freelancers who have a clear pain point. But what if you're building a consumer app? Would cold email still work? Lucas: It's harder, but not impossible. For B2C, you'd need to target people who are vocal about the problem online. For example, if you built a habit-tracking app for new parents, you could find new parent forums or Reddit threads and email individuals who posted about struggling to maintain routines. But the conversion rate will be lower — maybe 5 to 10 percent — because consumer pain isn't as acute as business pain. Luna: And you'd need to be even more careful about personalization. A mass email to parents would feel creepy. Lucas: Right. The personalization has to show you actually read their post. 'I saw you mentioned on Reddit that you're having trouble tracking sleep schedules — I built an app that might help.' That can work. But the bar is higher. Luna: Let's talk about tools. You mentioned Hunter and Mailshake. Are there cheaper alternatives for a solo dev on a budget? Lucas: Hunter has a free tier — 25 searches a month, which is enough to start. For sending, you can use Mailshake's free trial, or even use a simple Google Sheets script with a Gmail account. But if you're serious, invest in a tool like Lemlist or QuickMail. They handle deliverability better. Luna: What about the time cost? Manually personalizing 200 emails sounds brutal. Lucas: It took him about six hours over two days. But he said it was the best time he spent. Because those 50 beta users gave him feedback that shaped the product. One user asked for a time-blocking feature, another wanted integration with FreshBooks. He built both, and those features became the reason his product later got featured on a design blog. Luna: So the cold email wasn't just for acquisition — it was a feedback loop. Lucas: Exactly. And that's the deeper point. Cold email gets a bad rep because people think of spam. But when it's done with respect, targeting, and personalization, it's one of the few channels where you can have a real conversation with your first users. Luna: I think that's a great insight for anyone sitting on a finished product wondering why nobody's using it. Lucas: If today was actually useful to you, the way these stay ad-free is listener support — buy me a coffee dot com slash fexingo. Luna: Yeah, it keeps us independent and focused on practical stories like this one, not sponsored fluff. Lucas: So if you found this episode valuable, consider throwing a coffee our way. It makes a real difference. Luna: Alright, back to the strategy. One thing I'm curious about: how did he measure success beyond the 50 signups? Did he track activation or just signups? Lucas: He tracked activation — defined as someone who used the tool for at least three sessions. Out of those 50, 28 became active users within the first month. That's a 56 percent activation rate, which is solid for a beta. He also asked each user to fill out a short survey after their first week. Luna: What kind of questions did he ask? Lucas: Things like: 'What almost made you not sign up?' and 'What feature would you pay for?' He used those answers to prioritize his roadmap. One common answer was 'I almost didn't sign up because I thought it would be too complex.' So he simplified the onboarding flow. Luna: That's smart — turning objections into product improvements. Lucas: Exactly. And by the end of the beta, he had 12 users willing to pay for the premium version. That was his first revenue — 120 dollars a month from those early adopters. Not huge, but it validated the model. Luna: And he started with nothing but a list and a few hours of work. Lucas: That's the beauty of cold email for solo devs: it's low cost, high leverage, and if you do it right, it builds relationships. You can't buy that with ads. Luna: So for someone listening who wants to try this tomorrow, what's the one thing they should get right? Lucas: The subject line. If it doesn't get opened, nothing else matters. Make it specific and curiosity-driven, not salesy. 'Quick question about ' works way better than 'New productivity tool for you'. Luna: And the second most important thing? Lucas: The first sentence. Show you've done your research. Mention something specific about them — their work, a recent post, a project. That proves you're not a bot and that you care. Luna: I think that's a solid takeaway. Thanks, Lucas. This was one of those episodes where I feel like I could actually go and do this tomorrow. Lucas: That's the goal. Go find your fifty people.