Package Size Exceeding AWS Lambda Limit (250mb)

Is there any way to specify which dependencies are bundled on a per lambda basis? We have bumped into the lambda package size limit because of a large dependency that is used by a single function. We can create a separate Jets project for this function. But this seems to be a more general problem where as the number of functions increase each function may only depend on a small subset of dependencies, yet all dependencies are bundled with each function, needed or not.

Is there a way to specify a custom layer for a single function?

Tom