Tim Nolet started Checkly after living through the pain of broken signups, sales funnels and API endpoints at a German electric-mobility startup. Existing monitoring tools felt either too simple, too expensive or too enterprise-heavy, so he built an active monitoring product around Puppeteer scripts that could test real user flows like logins and checkouts.

He did not start with a polished launch. He spent about six months building part-time while freelancing, funded the work with savings and consulting income, and put roughly €20,000 of his own money into the company. A private beta brought around 200 signups from Betalist, Twitter and Hacker News, giving him feedback before he tried to sell broadly.

The growth that took Checkly to roughly $1,100 MRR came from compounding trust channels rather than one launch spike. Tim open sourced Puppeteer Recorder, a Chrome extension that eventually attracted thousands of GitHub stars and sent developer-aware users toward Checkly. He also invested serious time in long-form technical blogging, shared in communities like Reddit, Slack and Hacker News, and rewarded early adopters with meaningful discounts so they had a reason to take a chance on a young product.

The lesson is not that discounting magically creates revenue. Tim used discounts after he had a real developer pain, a beta list, and a credible open-source wedge. Checkly reached the first recurring-revenue milestone because every channel reinforced the same message: this was a monitoring tool built by a developer who understood the operational pain personally.