Recover old SmartApp source code?

Hello. I wrote a SmartApp to automate groups of lights with motion sensors and door sensors in 2014-1015. The lights were Connected by TCP, which stopped working when the TCP server was taken down in 2016.
Now there are Zigbee lights that should do the job. But SmartThings has moved to a new platform since then.
Is there a way to recover my old SmartApp source code?