As a technologist applying for jobs, I wanted to make my CV stand out, and figured I have a StackOverflow profile that could demonstrate my knowledge & communication skills, I had Google-Code/GitHub/BitBucket projects which showed examples of my code, OSS contributions, technologies I have used plus then LinkedIn, blogs, Coursera courses, Geeklist.. the list goes on - and more importantly, these were things that were all changing much faster than my traditional CV was.
On the flipside of that, as an employer trying to recruit technologists is really hard - CV screening doesn't rule out many candidates, and beyond that you are left to navigate technical tests & interviews which are fraught with difficulties in trying to really assess whether someone is actually fir for a job.
Nerdability started life as an idea that was entered in a cloud competition to build a webapp (some details here originally called NerdStar) - which it won. I then recruited two co-founders and we re-wrote a bunch of it (originally all data persistence was mongo, but switched that to relational) and launched it to the public!
In January this year (2015) we retired the application, we had somewhere in the region of 800 users signed up (with no active/paid marketing). We have currently parked the page and a basic user profile tour on nerdability.zz.vc and are in the process of moving this holding page back to nerdability.com.
Things that went wellThere was a lot of great things we learnt/that came out of the project, here are some highlights:
We contributed to OSS - During development I created a Spring-Social implementation for Khan Academy API and for the GeekList API - both of which are now listed on the Spring site as community projects.
The content driven marketing - As mentioned, we didn't do any marketing, just a few tweets, etc - but the big win was the blog. We setup a basic blog over at blog.nerdability.com (still up and running!) using blogger for hosting and just posted tech articles - tutorial type stuff plus more link-bait-y type stuff like new years resolutions for developers, or getting hackathon projects into production - and the blog drove lots of our traffic. The beauty was the people who visited/discovered our blog were a perfect match for our target demographic, so we just had plenty of placements for nerdability and the users just trickled in! The link-bait stuff would give us spikes of traffic, but the tutorial/how-to stuff still drives a few thousand unique views a week.
User response - The user response was good, we had a fair few early adopters who liked what we were doing and blogged/tweeted positively about the project.
Things that were hardCompetition - The weekend we were due to launch, I got an early beta-invite to StackCareers - with an almost identical value proposition, but they already have money and a massive developer community.
Two-sided marketplace problem - so we started getting users signed up, but there was little engagement as users couldn't really do much with their profiles - we had not companies/jobs listed, so beyond just sharing their profile links there was not much they could do. We were working on the company integration when we finished, but didn't get into it.