Where do you advertise job opportunities?

Probably the best way of sourcing people with an entrepreneurial mindset!

I second that! Tried everything else but nothing beats Angel.co, the best part being their new sorting options.

Particularly for remote work - I've found great opportunities here myself when I was job hunting and know many colleagues and friends who have had great success hiring from listing here. You can pay a bit more to highlight your post and make it stand out from the rest. Has a very simple interface and layout with typical categories for a start up. It also gets aggregated into the RemoteOk.io website so it will be exposed to a broader group of potential candidates as well.

This is also an interesting spin on things and acts more as a "marketplace" for tech companies to find talent within the pool of people who sign up. Acts kind of like a match making service, which is particularly useful if you are looking for a role that is super niche.

I use dou.ua very often and it's one of the most popular place for tech hiring

ain.ua has a job board, where many local startups put their jobs. It's good place for marketing hiring!

On Xpo, you can post unlimited job adverts to find the candidate you're looking for. The platform incorporates personality traits, too. This helps you to assess candidate personality before ever meeting them - and helps to avoid costly hiring mistakes. The site is still in beta, but it's free to join with no subscription fees and is full of innovative tools to help you reinforce your team with the best employees.

For startups in the UK, workinstartups.com plays a pretty crucial role in hiring.

Jobs board is here.

Recruitee is an ATS, but more than that, it's a culmination of all the job boards in one platform! You can post to free and premium (with discounts) sites of your choosing, and even ask the fantastic folks I work with for some promotion advice. The hiring resources and blog are also top notch for finding new avenues of job promotion.