Subscription commerce startup NatureBox launched 18 months ago to create a line of tasty, healthy snacks shipped to customers once a month. Today the company is announcing that it's raised an $8.5 million Series A round of funding led by General Catalyst and Softbank Capital. The funding will go toward expanding its engineering team, with an eye toward building new products to increase customer satisfaction. NatureBox is kind of like Birchbox for healthy snacks. For $20 a month, subscribers get a box full of food that can be an alternative to the usual crappy snack food that they eat on the go. All NatureBox snacks are nutritionist approved, and lack the high-fructose corn syrup, hydrogenated oils, trans fats, and artificial sweeteners, flavors, and colors that are included in typical snacks. The startup also tries to partner with local growers and independent food suppliers to source the materials. NatureBox currently has about 80 different healthy snack options available to send to customers, and adds about 5-10 new products per month, while occasionally removing others. It expects to have more than 100 options by year-end. But it's not just about creating a wide range of healthy snacks. NatureBox also has to get folks eating them. And so, the startup matches customers with snacks that they'll love, and -- more importantly, that fit their dietary restrictions. So far, the idea seems to be catching on. In 2012, the company shipped 50,000 boxes to subscribers. This year, it expects to increase that to more than a million annual shipments. But there's still work that could be done. That includes improving its data analytics and the algorithm matching products to customers, for instance. That's part of NatureBox's plans to grow its engineering team to better serve its customers, according to NatureBox CEO Gautam Gupta. It also plans to invest in product and marketing functions with the new funding. Last December, NatureBox had raised $2 million from General Catalyst, Redpoint Ventures, and a bunch of angels. The company is based in San Carlos, Calif. and currently has 35 employees, but is targeting 45 by the end of the year, according to Gupta.