Simplify code to run processes by using a function from the standard library
Cosmetic: make do block match style of other code
Exit through the normal mechanism on :exit to ensure that the cleanup code runs.
Cosmetic: more indentation and trading vertical space for regularity
Remove redundant import
Cosmetic: give things a bit longer names and switch many-def into case-expr
Refactor so REPL code is separate from startup and teardown code for the command line tool

Setting things up to add check for node.js in a nice way
Handle "executable not found" errors on Windows as well
Add a nice error message if node.js is not installed
Remove directories more safely

If you don’t have build/ or cache/ and exit without running anything,
an error was thrown before because we tried to remove non-existent
directories.
Check for node in a platform-independent way

calling readProcessWithExitCode resulted in a runtime error on Windows
Bump version number
Update changelog
Include Repl in pkg
Simplify continuation code by using ContT