There are usually a number of people in L1 roles looking to transition to more development. You can have them be L2 by having 1/3 of their time spent contributi

There are usually a number of people in L1 roles looking to transition to more development. You can have them be L2 by having 1/3 of their time spent contributing to bug fixes and small features of the software so they get to know it better. I dont think they would have to come from L1 from the same company / project though. Experience does allow one to learn faster, communicate more efficiently, etc. I think it's also good practice to have devs rotates on some small shifts of L1/2 so they don't get out of touch with the reality of maintaining their stack.