I need a custom step for workflows in slack that will autogenerate an alphanumeric number in sequential order

I'm looking to hire someone for a project that requires an autogeneration of an alphanumeric sequence for a Slack workflow. The sequence needs to start from the number 1, and the nubmer should be a combination of numbers and letters. I'm looking for someone who has good coding skills and experience working on this type of project. This project requires a lot of attention to detail, so I would also want them to be comfortable working with debugging, design, and implementation of new features. Thanks for your consideration!