If you market your services through Facebook groups, I built a free Chrome extension that automates the posting
I tutor locally on the side and kept losing 30 minutes every Monday to the same routine: open Facebook group, paste my ad, click post. Repeat 6 times. It was the most annoying kind of work because it required just enough attention to not be ignorable but was completely brainless.
So I built something. It's called Reposter. You save your message once, pick your groups, and it opens each one and pre-fills the composer so you just click Post. Built it in vanilla JS with Chrome Extensions Manifest V3, Supabase for auth, and Stripe for payments.
The hardest technical part was that Facebook's post composer runs on Lexical, Meta's own rich text editor. It rejects standard DOM text insertion methods completely. The fix ended up being Chrome's debugger API to simulate keyboard input at the protocol level. Took me a while to figure that out.
Launched with a free tier (4 groups) and Pro at $7/month for unlimited groups. Also added group discovery so people can search for niche communities by keyword and get recommendations based on their location and business type.
A few things I learned shipping this solo:
- The Chrome Web Store review process is surprisingly smooth if your permission justifications are clear
- Stripe + Supabase for a simple paid tier is genuinely fast to set up
- The hardest part wasn't building it, it was figuring out who exactly would pay for it and how to reach them
Would love feedback from other solo founders, especially on pricing and how to grow something this niche. And if you do local marketing through Facebook groups yourself, give it a try!
Chrome Web Store: https://chromewebstore.google.com/detail/reposter/klcefljmljgkojnjffjhpbmocnjdphlp
Landing page: https://noorps.github.io/reposter
Always open to feedback and a rating on the store would honestly mean a lot. 🙏