From a pragmatic standpoint you'll likely work until you're around 65, so as long as you have enough time to learn the field and understand it I'd say at 34 you

From a pragmatic standpoint you'll likely work until you're around 65, so as long as you have enough time to learn the field and understand it I'd say at 34 you have plenty of time. Credentialing for software development is much easier than fields like law or medicine, so as long as you can prove you can code well there will be plenty of opportunities open to you. Showing an open source project contribution or getting some certification might be a good start.