There are two primary metrics that we recommend to track adoption of Sorbet in a codebase:| sorbet.org
## Why does Sorbet think this is `nil`? I just checked that it's not!| sorbet.org
Classes are also values in Ruby. Sorbet has two ways to describe the type of these class objects: `T.class_of(...)` and `T::Class[...]`.| sorbet.org
Sorbet is a gradual type checker, which is a blessing and a curse.| sorbet.org
> This page describes the syntax of method signatures, or `sig`s. For a complete| sorbet.org
| sorbet.org
## Step 1: Install dependencies| sorbet.org
Sorbet provides the most value when it has a wealth of programmer-supplied| sorbet.org
As we've mentioned before, Sorbet is a [gradual](/docs/gradual) system: it can be| sorbet.org
RBI files are "Ruby Interface" files. Sorbet uses RBI files to learn about| sorbet.org