Stamps.com, a provider of Internet-based postage services, has acquired e-commerce shipping software company ShipWorks for $22 million in an all-cash deal.

ShipWorks works with online sellers such as PayPal and Amazon to offer multi-carrier shipping options. The St. Louis company will operate independently as a wholly-owned subsidiary. Its current management team will remain in place.

Stamps.com customers can print U.S. Postal Service-approved postage through its site. Though it struggled earlier this year, the El Segundo company posted net income of $11.2 million (68 cents a share) for the quarter ending June 30, 22 percent higher than the same quarter last year. Its revenue rose 7 percent to $34.3 million. During that same period, Stamps.com acquired Austin, Texas, shipment fulfillment company ShipStation.

“E-commerce driven package shipping is a very attractive segment within the mailing and shipping space,” Ken McBride, Stamps.com’s chairman and chief executive, said in a statement.

Shares of Stamps.com were up 67 cents, or 2 percent, to $33.53 a share at the end of trading Monday on the Nasdaq stock market.

Staff reporter Melissah Yang can be reached at [email protected]. Follow her on Twitter @MelissahYang for the latest in L.A. tech news.