Klarna Engineering with Marcus Granström

Klarna is a payments company headquartered in Sweden. Since being established in 2005 it has grown to handling $21 billion in online sales in 2017. Roughly 40% of all e-commerce sales in Sweden go through Klarna.

Klarna’s original differentiator was that it allowed users to checkout of e-commerce stores without entering in credit card information. Instead, the user enters an email address and registers with Klarna. This allows Klarna to assume the risk of the transaction, in place of the credit card company.

Klarna’s clever payment method became very popular, and 13 years later Klarna is a bank with a variety of financial services and payment methods. Marcus Granstrom is a director of engineering at Klarna. His work ranges from product development to systems architecture to management. His cross functional role has some similarity to Raylene Yung from Stripe, who is also an engineering director at a payments company, and was on the show yesterday.

Marcus walked me through the life of a payment hitting Klarna’s servers, and this served as a nice starting point for a conversation about Klarna’s infrastructure, their product, and their engineering practices.


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