Optimizely, a San Francisco-based provider of website testing solutions, has raised $28 million in Series A funding. Benchmark led the round, and was joined by Bain Capital Ventures and seed backers Battery Ventures, Google Ventures and InterWest Partners. www.optimizely.com
MarkLogic Corp., a San Francisco-based provider of an enterprise NoSQL platform, has raised $25 million in new VC funding. Sequoia Capital and Tenaya Capital co-led the round, and were joined by Northgate Capital and company CEO Gary Bloom. www.marklogic.com
WellTok Inc., a Denver-based developer of a social health management platform, has raised $18.7 million in Series B funding from Emergence Capital Partners, InterWest Partners and New Enterprise Associates. www.welltok.com
iRhythm Technologies Inc., a San Francisco-based developer of cardiac diagnostic monitoring solutions, has raised $16 million in Series D funding. Norwest Venture Partners led the round, and was joined by return backers New Leaf Ventures, Synergy Life Science Partners, Stanford University and Kaiser Permanente Ventures. www.irhythmtech.com
Treehouse Island Inc., a Portland, Ore.-based online coding education platform, has raised $7 million in Series B funding. Kaplan Ventures led the round, and was joined by The Social+Capital Partnership. www.teamtreehouse.com
Wandera, a mobile data optimization startup with offices in London and San Francisco, has raised $7 million in Series A funding from Bessemer Venture Partners. www.wandera.com
ParElastic Corp., a Waltham, Mass.-based cloud data management startup, has raised $5.7 million in Series A funding. General Catalyst Partners led the round, and was joined by return backers Point Judith Capital, CommonAngels and LaunchCapital. The company previously raised $3 million in seed funding. www.parelastic.com
OptionsCity Software, a Chicago-based electronic trading and market-marking platform, has raised an undisclosed amount of growth equity funding from Edison Ventures. www.optionscity.com
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