Form API Validaton (D8)
On a trip with coworkers, Jesse was expressing his surprise that Drupal core didn't contain some basic form validators for developers. A coworker then mentioned Form API Validation module. Jesse checked out the module and was instantly impressed by it, but noticed it had a large issue queue and was lacking some basic filtering functionality such as strip_tags and entity encoding. Jesse became a co-mainter of the project, bringing in many patches and fixing many open issues. Jesse later ported over the D8 version of the module, which he still currently maintains.