Adding methods to Oak's Context?

I am trying to figure out how to configure my Oak application/router so that my routes can do things like

ctx.customMethod()

ctx.customMethod()

, could someone point me in the right direction? I can only really find how to customize the

State

State

, but that would only let me do

ctx.state.customMethod()

ctx.state.customMethod()

– is that how you're supposed to do it instead of what I had in mind?