Mid-sized firms are struggling to secure the top talent as they miss out on some of the most attractive staff to start-ups or larger rivals prepared to give bigger salaries.
There has been plenty of noise made about the attempts to rival Silicon Valley with the development of the tech hubs and the investment in East London and it seems to have sunk in with younger job seekers.
"The young, talented, innovative people are leaving because they are interested in exciting start-ups so being in London, or one of these tech hubs, and having all of these new opportunities on their doorstep really opens up the possibilities for people," said Tash Whitmey, CEO of digital marketing agency EHS 4D.
Her comments were echoed by others at a UKFast event in London, where the warnings about job competition were echoed by others in the industry.
Elizabeth Varley, co-founder of the community and workspace for technology entrepreneurs, TechHub, said it was not only start-ups that were attracting staff.
"We have got the big companies that can pay the big salaries; they suck all of the talent from the entrepreneurial pool. The competition is fierce for the best people within the 'tech hub' areas like Silicon Roundabout," she said.
Jonathan Bowers, managing director of UKFast, said that the competition was not just restricted to London.
"This doesn't just apply to tech hubs, it is applicable across the industry. It is well known that there is a shortage of talent in the field and established mid-tier companies can find it difficult to compete with the excitement of start-ups or the massive salaries of the big tech player. They need to make sure that they are investing in making their workplace a great place to be," he said.