Extra Goodies
Browser Extension: Reason-tools
Reason-tools lets you quickly toggle between OCaml syntax and Reason syntax when you're browsing tutorials and documentations written in either syntax.
REPL
An online REPL: https://sketch.sh/.
The command line REPL rtop is one part of a (slightly) bigger toolchain of CLI tools for Reason.
re:bench
re:bench is an online benchmarking playground. It supports test cases written in Reason, OCaml and JavaScript, and allows sharing of benchmarks through unique URLs. It's compiled to JS using BuckleScript.
Redex
Redex: the Reason packages registry.