Twitter Inc., which has taken several steps to marry shopping with its communication platform, took another today with the acquisition of CardSpring Inc., which lets retailers and publishers craft payment card-linked promotions. Terms of the deal were not disclosed.

CardSpring’s platform lets merchants add a promotion or discount to a specific payment method. Then when a consumer uses that payment method, such as a Visa card, it can trigger a discount for the consumer.

The move builds on Twitter’s previous e-commerce-related initiatives. For instance, earlier this year it began letting consumers add items to their Amazon.com carts without leaving the social network. And last year it launched a program that let American Express Co. cardholders access exclusive deals by posting to Twitter using retailer-specific hashtags, such as #AmExZappos for $30 off a $150 purchase at Zappos.com. The company also introduced a social gifting program last year with Starbucks Corp. that let shoppers send coffee to friends on its platforms.

“As we work on the future of commerce on Twitter, we’re confident the CardSpring team and the technology they’ve built are a great fit with our philosophy regarding the best ways to bring in-the-moment commerce experiences to our users,” Nathan Hubbard, Twitter’s head of commerce, writes in a blog post.

CardSpring will continue to maintain its platform. The vendor says that at Twitter its team will work with its publisher, financial and retail partners to create new ways consumers can shop.