Obviously: if speed of development and speed of program were non-problematically compatible, everybody would always go for both (why lose speed, if you can have the same development experience)? But speed requires several things, like more careful algorithms and program design, custom solutions instead of one-size-fits-all libraries and frameworks, more care regarding memory usage, time spend for optimization, use of a statically typed language as opposed to a higher level scripting one, slower build/jit times (as opposed to interpreter), and so on...