If you’ve worked in the technology industry long enough, you’ve seen how open source has seized a significant slice of the market-share pie in a number of categories, including servers and smartphones. That means a rising number of companies need tech professionals experienced in Linux and open-source.

According to the 2016 Open Source Jobs Report, created through a partnership between Dice and the Linux Foundation, 87 percent of hiring managers say it’s hard to find open source talent, even as 59 percent indicate that they’re looking to increase their open source hiring this year. (As part of the report, which you can download here, Dice and the Linux Foundation surveyed 4,500 open source professionals worldwide.)

That means tech pros with the right mix of open source skillsets and experience can find employers anxious to employ them—provided the tech pros are certified, and their skills are up-to-date. More than half of surveyed hiring managers said they prioritized hiring candidates with formal open source training, and 44 percent suggested they’re more likely to hire those with certifications.

Among open source professionals surveyed by Dice and the Linux Foundation, 90 percent said they kept their skills up-to-date by reading books and online resources, including free tutorials. Another 60 percent said they took online training courses, while 45 percent attended conferences and/or events.

Some 42 percent of those surveyed kept their skills current through social and professional networking. Roughly 41 percent suggested they contribute to open-source software projects, and 35 percent went to open source meet-ups. Only 23 percent indicated that they attended instructor-led open source training.

When asked about the most important open source skills, 50 percent of those surveyed cited cloud technologies (such as OpenStack and Cloud Foundry); 19 percent said containers (i.e., Docker); 16 percent indicated security technology; 9 percent said networking technologies, and 5 percent said “Other.”

For much more data on how open-source professionals are faring in the industry, download the Jobs Report here.