I think it'd be hard to make any real money doing this as a purely side effort.
Low skill work, a company willing to hire an external contractor is just going to look offshore.
High skill work, a company is likely going to have an establish contractor finding network/process, and reject independent folks as either being too cheap (not serious) or too inexperienced.
So (to my eyes) the only 'customer base' is, effectively, lazy folks willing to "subcontract" you to do their own work, which seems like a flighty, not-worth-the-risk kind of customer to chase.
There are 2 listed Ignition contractors on Fiverr, nothing on Freelancer.
A bunch of people on here do side hustle module development, as it is not a widespread skill and it is very good for differentiating your skills from the average Ignition user.