Just three months after raising $40 million in a Series B funding, German HR and recruiting platform Personio is announcing it has acquired Rollbox, the Spanish startup that offers an API-based payroll solution. The two companies had been working together, but now Personio is bringing Rollbox’s tech and team in-house.

The full terms of the deal remain undisclosed. However, I understand the acquisition consists of a combination of cash and equity. This sees a number of Rollbox’s investors being issued shares in Personio, while others have exited entirely.

Founded in 2016, Rollbox was backed by SaaS investor Point Nine and Berlin-based VC La Famiglia, along with individual investors Paul Forster (founder of Indeed) and Brian Pietras (VP Strategy at Workday).

Meanwhile, I’m told Rollbox’s founders, Xavi Leal and Ismael Sanchez, are joining Personio and will be key members of the management team going forward. The Rollbox brand will be decommissioned and the tech merged into the Personio platform. Rollbox customers are being invited to move over to Personio.

“This deal will allow Personio… to extend is HR Operating System by [adding] a fully integrated payroll engine that can help customers fully automate payroll,” Personio co-founder and CEO Hanno Renner tells TechCrunch. Features include real-time validation, automated government, insurance and tax communication and on-the-fly payroll calculations.

Citing Rollbox’s international footprint — the company operates in Spain, U.K. and Germany — Renner also says the acquisition will help facilitate Personio’s internationalization across Europe, which began earlier this year.

On that note, Personio says it will retain both offices and all employees. Aggregated headcount will now sit at more than 200 employees: currently 190 employees in Personio’s Munich HQ and 25 employees in Madrid.