I consider myself a polyglot. Learning is part of the work and I’m good at it. Nevertheless, it can be helpful to already be familiar with some things. Here is an incomplete list of the things I’m familiar with.
Regulation and Standards: PIPEDA (Personal Information Protection and Electronic Documents Act), GDPR (General Data Protection Regulation), SOC-2 / SSAE 16 (Service Organization Controls), OECD Privacy Principles
Certifications: IAPP’s Certified Information Privacy Technologist (CIPT)
Technologies and Platforms: Database internals and optimizations, RDBMS, SQL, PostgreSQL, MySQL, Vertica, Presto, Hadoop, HDFS, PAXOS, ZooKeeper, AWS, Spring/SpringBoot
Languages: Python, C/C++, Java, JavaScript, Ruby