Ask HN: How do you demonstrate experience and competence as a developer?

Hi all,

So this is something I've been thinking about quite a bit.

With clients, I usually mention a project that I've done which is similar to what they'd like to me to do (or that has used similar technologies).

But I'm wondering if there isn't a better way.

My work history is pretty sporadic. Having had many long periods of entrepreneurship as well as freelancing.

I also don't have any formal qualifications, though I've been programming professionally for over 10 years now.

For the freelancers and the recently employed on here.

How do you demonstrate your experience and competence as a developer?