Austin, Texas-based enterprise software development firm Headspring Systems plans to hire 100 app developers by the end of the year, with most of the hires based in Dallas, where it’s opening a new office. The company nearly tripled its headcount last year and expanded to Houston. It plans a Chicago office in 2015. The company focuses on custom application development, business intelligence and systems integration. In February, it launched a mobile division. Opening in May, the Dallas office will hire in software development and mobile application development. Available positions include senior .NET developers in Austin, Houston and Dallas. “The demand for us is so high right now that we just can’t fill the positions fast enough,” J.T. McCormick, the company’s president, told the Dallas Business Journal.