Mayor Gavin Newsom&'s claim that Foursquare is a San Francisco startup just got a little bit more accurate. Foursquare, which has famously worked out of the Square offices here in SF for quite sometime, has finally bit the bullet and made its West Coast dalliance official today with a &''We‚a4‚¬‚a4„re heading west!&'' blog post.

&''In the past year, we had a major growth spurt: from about 100,000 to over 4.5 million users' from a single phone platform to six' from 50-person foursquare flashmobs to 1,000 person epic swarms' and we now have thousands of developers building on the the foursquare API. The biggest challenge: hiring fast enough to support that surge. Despite growing from 5 employees to 35, we can‚a4‚¬‚a4„t expand as quickly as we want.

So, to help attract the best talent in the world, we decided it‚a4‚¬‚a4„s time to open an outpost in San Francisco.&''

The location based startup will not be moving from San Francisco Chronicle Building where it&'s set up defacto shop since summer, and Square will be freeing up more room for the company to hire a full team of West Coast engineers in addition to its 35 current employees. Four employees already work on the West Coast include Tristan Walker, Holger Luedorf and two operations engineers.a4s‚ With $21.4M in funding led by Andreesen, Foursquare has definitely got room to grow.

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