Requirements:
Strong C programming using a POSIX API, including memory management, file IO, networking; ideally on Linux, but UNIX, *BSD experience OK.
Strong shell scripting; csh/tcsh desirable, but sh/bash OK.
Algorithms and data structures -- trees, hashing, parsing, complexity, etc.
Solid version control systems, CI/CD pipelines, etc.; git, Gitlab, Docker, desirable.
Desirable but not required: working knowledge of one or more of Go, Lua, M, Python; M and Go especially desirable.
Excellent verbal and written technical English for communication with other developers.