I’ve won many contracts this way. If you want to know more email is in my profile.
For example here's my comment in the latest thread: https://news.ycombinator.com/item?id=36154077. I post monthly and typically get 2-5 inbounds.
I'll also note that I haven't emailed any freelancers who posted in the thread. I rely on people seeing my comment and reaching out to me.
My advice would be:
* After posting your "seeking work" comment, cmd-f/ctrl-f for "seeking freelancer" and email any that look interesting to you. Reach out.
My advice on reaching out:
* Make your emails short
* You can leave your rate out of the first email unless they explicitly ask for it, that way if they don't reply you can tell if it was more likely because they no longer have the need or they weren't interested in your background, whereas if they don't reply after they ask for your rate and you send it, then you know it was probably out of their range
* You can politely include a soft deadline. For example - "it would be helpful if you could let me know sometime in the next 7 days whether you're interested or not, thanks" - you can replace 7 with something else but I wouldn't go shorter than 4. This way, if they don't reply by the 8th day, you can treat it as a gentle "no" and you can direct your energy elsewhere
* Include what the poster asks for (if they ask for links to prior projects you've made, include those)
* Don't try and make it sound impressive, instead just go for "fast facts" - include your links, include what they ask for, and leave it at that. You can send the same thing to each person, other than modifying for any specific requests people have.