A fast-growing Charleston technology firm is expanding and moving its business to a big urban renewal project taking shape on Morrison Drive on the upper peninsula.

Blue Acorn, which helps its clients sell more goods online, announced last week it will be taking space in Raven Cliff Co.'s new development, Half Mile North.

Kevin Eichelberger, founder and CEO of the e-commerce agency, said his payroll has swelled to more than 50 employees from one in just five years. It's currently based in a building at Rutledge Ave and Huger Street.

The company needed "to find at least twice the space we have now" and wanted to stay on the peninsula, Eichelberger said. It will occupy a former warehouse that's being renovated and be expanded. Blue Acorn was recently ranked No. 474 in Inc. magazine's annual list of the fastest-growing private U.S. companies.

"It is so rewarding to see our tech companies, like Blue Acorn, enabling great employment opportunities here in Charleston while leveraging their success to revitalize Charleston's upper peninsula," Mayor Joe Riley said in a statement.

In addition to Blue Acorn, two other tenants that have committed to space at Half Mile North: the consulting firm SIB, which will be relocating from Meeting Street, and Edmund's Oast, a brew pub being launched by the founders of the Charleston Beer Exchange in 2008.

The first phase of Half Mile North is expected to be completed next year. It encompasses nearly the entire block between Morrison Drive, Meeting Street, Brigade Street, and Williman Street.

The second phase will include the western half of the block just to the south. It will likely be completed by mid-2016.

Raven Cliff is headed by Stephen Zoukis, a former partner with Atlanta-based Jamestown Properties who lives on Sullivan's Island.