  Transient gradual typing imposes run-time type tests that typically cause a
linear slowdown in programs' performance. This performance impact discourages
the use of type annotations because adding types to a program makes the program
slower. A virtual machine can employ standard just-in-time optimizations to
reduce the overhead of transient checks to near zero. These optimizations can
give gradually-typed languages performance comparable to state-of-the-art
dynamic languages, so programmers can add types to their code without affecting
their programs' performance.
