<p>My platform turns every Stripe payment into a compliant invoice in the customer’s local invoicing or e-invoicing system, automatically. It connects Stripe with 20 tools across Europe, including Fakturownia/InvoiceOcean, wFirma, iFirma, inFakt, Fakturoid, SuperFaktúra, Fatture in Cloud, Aruba, Epsilon Smart, DDD Invoices, Billy and Poland’s national KSeF system.</p><p>I spent 10 years solving accounting problems for SMEs in Poland and kept seeing the same thing: founders selling on Stripe while someone retyped every payment into an invoicing tool by hand. With e-invoicing becoming mandatory across Europe (KSeF in Poland in 2026, Slovakia in 2027, ViDA next), I built my platform in 2025 to fix it.</p><p>The model is simple: the first client in a new country helps test the new connector, a new integration ships in a few days to two weeks, and there are no setup fees. Setup is about 90% self-serve: a restricted Stripe API key plus the invoicing tool credentials.</p><p><b>Key highlights:</b></p><ul> <li>Annual revenue: ARR 33,746 PLN (~$9.2k)</li> <li>Annual profit: 33,746 PLN (~$9.2k)</li> <li>Churn rate: 2.6% of subscribers last month, ~6% average over the last 6 months. Net MRR churn 1.2%</li> <li>LTV: ~630-1,445 PLN depending on the churn period</li> <li>CAC: near zero, 99% of customers come from organic search</li> <li>Other: 74 active subscribers (74 of 116 ever acquired still active), ARPU 38 PLN, 20 integrations</li> </ul> <p><b>Team</b></p><p>Two people. Me, Kamil: product and customers. A software architect: architecture and code review, paid on a contract with no equity. After the sale, both of us are open to working with the new owner on a contract.</p><p><b>Tech Stack</b></p><p>Symfony 7 (PHP 8.2+), MySQL 8, Twig + Tailwind, Stripe and KSeF PHP clients. Runs on a single VPS, deployed via GitHub Actions.</p><p><b>Marketing and growth</b></p><p>Growth is 99% SEO. Customers search for “Stripe + their invoicing tool” or “Stripe + KSeF” in their own language, find our platform, connect and pay. No sales team, no ad budget.</p><ul> <li>Organic search: landing pages per integration and country. My platform also shows up in AI assistant answers for Stripe + KSeF, SDi (and so) questions.</li> <li>Paid ads (Meta, Google): small tests only, never a real channel.</li> <li>The remaining ~1%: referrals and the Stripe community, where I lead the Warsaw chapter.</li> <li>Result: 116 subscribers acquired at near-zero CAC, MRR from 0 to 2,812 PLN in about 16 months. New signups peaked in spring 2026 around the KSeF deadlines and settled at a steady pace after.</li> </ul> <p><b>Startup assets</b></p><ul> <li>.com domain with localized landing pages and their organic traffic</li> <li>Full codebase with 20 connectors (most in production, 4 in beta)</li> <li>74 active subscribers with Stripe subscriptions, plus data of all 116 customers ever</li> <li>Ebook lead magnet for accountants</li> <li>Walkthrough videos in several languages</li> <li>Meta and Google Ads accounts with campaign history.</li> </ul> <p><b>Risks</b></p><ul> <li>Regulatory changes per country. The platform only pushes payment data. Compliance, PDF generation and submission to national systems sit with the invoicing tool. Connectors are modular, so a change touches one module.</li> <li>Third-party API changes. Per-connector tests and a small, isolated codebase per provider.</li> <li>Beta connectors (Yuki, mPohoda, Fakturoid, Aruba): clearly labeled, built further only with a real client.</li> </ul> <p><b>Summary</b></p><p>E-invoicing is becoming mandatory across Europe and Stripe doesn’t solve it natively. It is a working, paying product in that gap, with near-zero CAC: 99% of customers come from organic search, and that traffic transfers with the domain. It’s underpriced, cheap to run, and the hard part, knowing how invoicing works in each country, is already baked into the code. I’m moving to client projects, so I want someone who’ll grow the product, and I’ll stay available to help.</p><p>✅ $8,600 TTM revenue</p><p>✅ 74 customers</p><p>✅ Business model: SaaS</p><p>✅ Built with PHP, TailwindCSS, Symfony</p>