I do employ a few people now, but in the beginning, it was just me for about 4 years:
OSREC - https://osrec.co.uk Bx - https://usebx.com
Got started with OSREC because I could see a gap for a good suite of tools that could automate mundane data tasks in banks and hedge funds. Also, I did not enjoy my investment banking job.
Got started with Bx because many people complained to me about Quickbooks/Sage/Xero and I thought I could do better :)