People shove too much complexity into a lambda. It seems like a great idea to have this infinitely scaling lambda with no infrastructure to run, but what you're

People shove too much complexity into a lambda. It seems like a great idea to have this infinitely scaling lambda with no infrastructure to run, but what you're trading off is developer experience. It sounds like your lambdas are calling other lambdas. If this is true, rethink your architecture. If you have a thin, minimal code wrapper that translates your lambda invocation event into some sort of function invocation, it shouldn't be hard to test. Your external dependencies should be modeled as interfaces that can have fake implementations injected that either return pre-canned responses or implement things in memory. Without more info about what you're doing, it makes it really hard to know what specifically is stopping you.