Surprise telemetry is deeply unethical. Putting it in the README is borderline OK, I guess. However, even supposing it's OK, a "single ping on use" is only real

Surprise telemetry is deeply unethical. Putting it in the README is borderline OK, I guess. However, even supposing it's OK, a "single ping on use" is only really feasible if the system has "main()" and some reasonably persistent usage. If you're a small tool - or a library, like we were, "single ping on use" might result in thousands of systems "beaconing" back to home base per hour. For the area we were in (pattern matching is basically computer security-adjacent), this would have been equivalent to shipping malware in terms of sheer career-destroying potential. Not everything is a long-running desktop app.