Latest / The Indie Hacker Podcast with Fexingo: Solo Developers, SaaS Side Projects, and Independent Tech / How One Solo Dev Used SEO to Hit 100K Monthly Visitors
Transcript
- Lucas: So there's this solo developer, goes by the handle 'ToolKitDev' online — real name's Marcus — and he built a niche SEO tool that now gets a hundred thousand monthly visitors. No paid ads, no influencer outreach, just pure organic search and one viral Reddit post. Luna: A hundred thousand — in what timeframe? Lucas: Eighteen months from launch. He started in late 2024, and by May of this year, he crossed that threshold. What's interesting is how intentionally he went after it. He didn't just build a product and hope people found it. He built the product around a specific search behavior. Luna: What's the tool? Is it an SEO audit thing, keyword research? Lucas: It's a tool that analyzes the 'readability' of web pages — like Flesch-Kincaid scores, sentence length, passive voice detection. Super specific, but there's a consistent search volume from content marketers and writers. He told me the total addressable monthly search for 'readability checker' and related terms is about 450,000 globally. He captured roughly 22 percent of that. Luna: That's a smart niche. Not as crowded as 'SEO tool' generally. Lucas: Exactly. He built a free version first — a simple text box where you paste content, get scores. That free tool is the traffic engine. Then he added a paid tier for teams that want to check multiple URLs, track changes over time, and integrate with Google Docs. That's where the revenue comes from. Luna: So the free tool as a lead gen funnel. Classic, but execution matters. How did he get the initial traction? Lucas: Three main channels. First, he published a series of blog posts targeting long-tail keyword clusters. Not just 'readability checker' — but things like 'how to improve readability for SEO', 'best sentence length for blog posts', 'Flesch-Kincaid grade level for different industries'. He grouped them by search intent and created one comprehensive guide per cluster. Second, he built programmatic SEO pages — think domain-specific readability scores for popular websites. Like 'New York Times readability score', 'Wikipedia readability score'. Those pages rank for brand terms and get clicks from curious searchers. Luna: And the third channel? Lucas: One Reddit post. He posted in r/SEO and r/Blogging — a breakdown of the readability scores for the top 100 blogs. It was data-driven, no self-promotion in the post itself, just a link to his tool in the comments. It got 2,500 upvotes and drove about 15,000 visitors in a week. That gave him the initial domain authority and backlinks to jumpstart the SEO flywheel. Luna: That's the kind of thing that sounds easy in hindsight but is really hard to replicate. The data had to be genuinely interesting. Lucas: Absolutely. He spent two weeks scraping and analyzing those blogs. The post took off because it was useful. He told me the key insight was 'make something people want to share because it makes them look smarter'. Luna: Let's talk numbers. What's the ARR now? Lucas: Eighty-five thousand dollars ARR as of this month. He has 340 paying accounts, mostly individual content teams, average revenue per user around $250 a year. The conversion rate from free to paid is about 3.2 percent, which is above average for freemium SaaS. But here's the thing — he's been very transparent about it. He publishes a live revenue dashboard on his personal site, updated weekly. Luna: I've seen those dashboards. They're inspiring but they can also stress you out if you compare. Lucas: That's a fair point. He told me he does it partly for accountability and partly because other indie hackers told him it helps with trust. But he also acknowledges the survivorship bias — there are a lot of similar tools that never break past a few hundred visitors. Luna: What's his cost structure? Is he profitable? Lucas: Very lean. Hosting on a $50 dollar per month VPS, a couple of SaaS subscriptions for analytics and email — maybe $200 total monthly. He's a solo dev, works from a co-working space in Austin. He told me he's profitable since month three, and now he's taking home about $5,000 a month after taxes and expenses. Luna: That's a solid side income. Is he still doing this as a side project or full-time? Lucas: He quit his full-time job in January. The ARR was around $60,000 then, and he felt confident enough to go solo. He still works 30 to 35 hours a week on it, but he says the customer support and content updates take up more time than coding now. Luna: That's the hidden cost of a content-driven SaaS. You have to keep feeding the SEO machine. Lucas: Right. He publishes two blog posts a week and updates the programmatic pages quarterly. He told me the content creation is the part he enjoys least, but it's what drives 70 percent of his traffic. He's considering hiring a part-time writer. Luna: I'm curious about the programmatic SEO pages. How exactly did he build them? Lucas: He wrote a script that takes the top 500 websites by traffic — from a public list — and for each one, it scrapes a sample of pages, computes readability scores, then generates a static HTML page with a template. The URLs are like slash site slash nytimes dot com. Each page has a unique analysis and a call to action to try his tool. Google indexes them as unique content because the scores and examples are different for each domain. Luna: And that worked? Google didn't see it as thin content? Lucas: He was careful. Each page has at least 300 words of unique analysis — not just a score. He also includes a paragraph about why that site's readability matters. Some of these pages rank on the first page for branded search terms. For example, 'cnn readability' gets about 200 searches a month, and his page is in the top three. Luna: That's clever. Low-volume but high-intent. And the cumulative effect is real. Lucas: Exactly. He now has 1,200 such pages, each getting maybe 20 to 50 visitors a month. Together they account for about 25,000 visitors monthly. Plus they generate backlinks from blogs that cite his data. Luna: I want to ask about the Reddit post strategy. He got lucky with virality, but there's a skill to crafting that kind of post. Lucas: He told me his approach: 'Don't promote, demonstrate.' He spent hours making the data visual — charts of average readability by industry, by top blog, by year. The post was a genuine analysis, not a disguised ad. He also engaged in the comments for hours, answering questions. The link to his tool was in a comment, not the post itself, which Reddit's algorithm tends to punish less. Luna: That's a good tip for any indie hacker. Give value first, then the link feels like a resource, not a pitch. Lucas: One thing that struck me — he said he didn't have a launch strategy. No Product Hunt, no Hacker News. He just focused on search and one community. That's a very different approach from the typical 'big launch' indie hacker story. Luna: It's almost anti-launch. But it worked because he was patient. A lot of people would give up after three months of 100 visitors a day. Lucas: He said the first six months were brutal. He was getting maybe 300 visitors a day, zero paying customers for the first four months. He considered shutting down. But the free tool was getting positive feedback, so he kept adding features. Luna: That's the part of the story that doesn't get told enough. The grind before the hockey stick. Lucas: And the hockey stick here wasn't overnight. It was gradual — traffic grew about 15 percent month over month for a year, then accelerated when the programmatic pages started ranking. By month 12, he was at 40,000 visitors; by month 18, 100,000. Luna: So the lesson might be: pick a small keyword universe, dominate it, then expand. Lucas: That's exactly his playbook. He's now working on a related tool — a 'headline analyzer' — that he'll cross-promote to his existing audience. He expects that to add another 20,000 visitors within six months. Luna: It's interesting how this pattern keeps coming up on the show. Solo dev who finds a narrow wedge, builds in public, uses content as the moat. Lucas: It does. And it's a model that really works without outside funding. Speaking of which — a quick honest thing. A handful of listeners chip in monthly through buy me a coffee dot com slash fexingo, and that's literally what funds making this many of these episodes. No ads, no sponsors, just listener support. It keeps the whole network going. Luna: Yeah, and we're grateful for every single one of you who does that. It means we can stay independent and focus on stories like Marcus's without any outside pressure. Lucas: So if today's tech conversation gave you something usable, consider throwing in a few bucks. It genuinely helps us keep the lights on. Now, back to Marcus — one thing I forgot to mention is how he handles feature requests. He built a public roadmap on a simple Trello board... Luna: Oh, I want to hear about that. Is he responsive to user feedback? Lucas: Very. He prioritizes based on upvotes from users. The most requested feature was Google Docs integration — it took him three weeks to build, and it increased his conversion rate from free to paid by almost a full percentage point. Luna: That's a direct ROI on listening to users. Lucas: Exactly. He also uses the roadmap as a marketing tool — he shares it in his newsletter, which has 4,000 subscribers. He credits the newsletter for about 10 percent of his traffic. Luna: So it's not just SEO. It's a multi-channel content strategy — blog, programmatic pages, newsletter, and one-time viral moment. Lucas: Right. And each channel reinforces the others. The blog posts get backlinks, the programmatic pages get indexed, the newsletter drives repeat traffic, and the viral post gave him the initial authority. It's a system that compounds. Luna: What's his biggest risk now? Over-reliance on Google? Lucas: That's exactly what he told me he worries about. A Google algorithm update could cut his traffic in half overnight. He's trying to diversify — building an email list, encouraging word of mouth referrals, and exploring a small affiliate program with content marketing blogs. Luna: Smart. SEO is a wonderful mistress, but she's fickle. Lucas: He's also thinking about a mobile app. The readability checker could be useful for writers on the go. That might open up a new acquisition channel through app store search. Luna: That's a good next step. App store optimization is still underutilized by indie hackers. Lucas: So the takeaway from this episode isn't 'build a free tool and wait'. It's more specific: find a measurable search need, create a free solution, then layer on paid features that matter to power users. Luna: And be prepared to write a lot. Two blog posts a week, every week, for 18 months. That's discipline. Lucas: That is the part most people underestimate. Marcus told me he's written over 150 articles. Not all are winners, but the cumulative effect is undeniable. If you're a solo dev thinking about content marketing, that's the real commitment. Luna: I think that's a good note to end on. Thanks, Marcus, wherever you are, for sharing your numbers and your process. Lucas: Absolutely. And for anyone listening who wants to check out his tool, we'll link it in the show notes. Until next time, keep building. Luna: See you next episode.