For languages, I see right now strong demand for:
- Python: as a first language of choice replacing Visual Basic or Java.
- Scala: as an alternative for both Python and Java for big data loads. Probably it could also work as an embedded language instead of LUA, but who knows.
- Swift and Kotlin for Mobile development.
- Systems and embedded programming (aka building native binaries): GO and Rust. Go looks very good since it was developed by the fathers of C and AWK (Pike, Kerningan, Ritchie). Rust seems more complicated at first sight.
- Javascript: plus some html5 (react,react native, vue, vue native, etc.) for web+mobile agencies.