Is worker instance reused across threads in Kicks (Sneakers issue #244)?

[rubyonrailsworks]

Really appreciate you reviving this project — I’m sure many Sneakers users are grateful for it.

• Background
  In the original Sneakers repo, issue #244 reported that a worker instance can be reused across multiple threads, making instance variables not thread-safe.
  Since Kicks is the community continuation of Sneakers, I’d like to confirm the current behavior in Kicks.

• Question
  In Kicks, when threads > 1, does each thread get its own worker instance, or is a single worker instance reused across threads?