Latest / The Indie Hacker Podcast with Fexingo: Solo Developers, SaaS Side Projects, and Independent Tech / How a Solo Dev Built a SaaS That Protects Privacy
Transcript
- Lucas: So there's this interesting spike in the Chrome Web Store data from late 2025. Privacy-focused extensions saw a collective 40 percent increase in installs over the prior twelve months. Luna: Forty percent? That's huge. Were people just getting more aware after all those third-party cookie deprecation headlines? Lucas: Partly. But the story I want to focus on today is about one developer — let's call him Alex — who built a privacy SaaS that's now doing around fifteen thousand dollars a month in recurring revenue. And he did it almost entirely alone. Luna: Fifteen K MRR from a Chrome extension? That's impressive. What does it actually do? Lucas: It blocks tracking scripts and fingerprinting — the kind that advertisers use to build profiles even after you delete cookies. But here's the twist: instead of just being a free tool like Privacy Badger or uBlock Origin, Alex charges a subscription. Nine dollars a month, or ninety-nine a year. Luna: And people actually pay for something they could get for free? How does he justify that? Lucas: That's exactly the question I had. He told me the key difference is transparency and control. His extension gives users a detailed log of every script that tried to run, which domains it came from, and the option to block on a per-script basis. Most free blockers just apply a blanket list. Luna: Right, so it's a power user tool. But getting people to pay for a browser extension is still a tough sell. Lucas: It is. Alex launched on Hacker News back in early 2024. He got about 500 upvotes and a ton of feedback — mostly asking why anyone would pay when Ghostery exists. Luna: Ouch. So what did he do next? Lucas: He took the criticism and added a feature that became his differentiator: a 'privacy score' for each website you visit. It's like a credit score but for tracking. You visit a site and the extension gives you a rating from A to F based on how many trackers it uses. Luna: That's clever. It gamifies the experience a bit. Did it help with conversions? Lucas: Massively. Within three months his free-to-paid conversion rate went from 0.8 percent to 3.2 percent. He hit fifteen hundred dollars MRR by June 2024, and it's been growing steadily since. Luna: So the privacy score became the hook. I can see why — people love seeing a bad grade and wanting to fix it. Lucas: Exactly. And he built a small viral loop: every time you visit a site, the extension shows the score in the toolbar. Users started tweeting screenshots of sites with an F, tagging the company. Some brands actually reached out to ask how to improve their score. Luna: Wait, that's interesting. So businesses started caring about their privacy score as a reputational metric? Lucas: Yeah, a few medium-sized e-commerce companies contacted him offering to pay for a business tier — they wanted to audit their own sites and see what their users see. That's when Alex added a team plan at $49 a month for up to five seats. Luna: That's a smart upsell. So he went from B2C to B2B without even planning it. Lucas: Right. And today, about 40 percent of his MRR comes from those business accounts. The rest is individual subscribers. He's at roughly 1,600 paying users total. Luna: And he still runs it solo? No employees? Lucas: He's got a part-time contractor helping with customer support — one person, about fifteen hours a week. Everything else, including the backend infrastructure and the machine learning model that classifies trackers, is his own work. Luna: Machine learning? I didn't expect that in a privacy extension. Lucas: That's the technical moat. He trained a small neural network to identify new tracking scripts based on behavior, not just known signatures. So even if a tracker changes its code, the extension can flag it. That's hard to replicate. Luna: Okay, that's genuinely impressive. Most indie hackers aren't building ML models. Lucas: Alex had a background in data science before going indie. But he said the model itself is actually pretty simple — just a few hundred lines of Python. The hard part was labeling the training data. Luna: I bet. So what's the biggest challenge he faces now? Lucas: Churn. His monthly churn rate is about 5.5 percent, which is high for a SaaS. He says most people cancel after three or four months because they feel the extension is working — they don't see trackers anymore, so they forget why they needed it. Luna: That's a weird problem — the product is too effective. How does he address it? Lucas: He's experimenting with a monthly 'privacy report' email that shows how many scripts were blocked, which sites were cleanest, and a comparison to other users' averages. The idea is to make the value visible even when the extension is silent. Luna: That's smart. Make the invisible visible. If it works, it could bring churn down significantly. Lucas: If he gets churn below 3 percent, he could be looking at $30,000 MRR within a year. And he's thinking about adding a feature that lets users see which companies are behind the trackers — like, 'This script is owned by Meta.' Luna: I'd pay for that alone. It's one thing to block trackers, but knowing who's trying to track you adds a layer of accountability. Lucas: Exactly. And that kind of transparency is exactly why listeners who care about building ethical tech might find this story useful. Luna: Speaking of which, if today's conversation gave you something usable — a new angle on monetization, a way to think about churn, or just the motivation to start — consider supporting the show. We keep it ad-free and listener-supported. You can do that at buy me a coffee dot com slash fexingo. Every bit helps us keep going. Lucas: Yeah, it really does. And it lets us keep diving into stories like Alex's — the ones that don't make tech headlines but teach real lessons. Luna: So back to Alex's story. One thing I found surprising is that he doesn't have a mobile app. Most privacy tools have mobile versions now. Lucas: He told me it's intentional. Mobile extension ecosystems are more restrictive — especially on iOS. He'd rather focus on desktop where he can deliver the full experience and keep the codebase small. Luna: Fair. A solo dev has to pick battles. So what's next for him? Lucas: He's exploring a partnership with a small VPN provider — offering a bundle for $12 a month. If that works, it could open a distribution channel without him having to build a sales team. Luna: That's a smart low-risk move. And it stays in the privacy space, so the brand message is consistent. Lucas: Exactly. And it shows how a solo developer can build something meaningful without venture capital, without a team, and without compromising on ethics. Luna: One concrete takeaway for our listeners: if you're building a tool that solves a specific pain point, think about how you can measure the problem in a visible way. Alex's privacy score made the invisible threat tangible — and that turned into revenue. Lucas: Great note to end on. Luna, thanks for the conversation. And to our listeners, we'll be back tomorrow with another indie hacker story. Luna: See you then.