Rich Bradbury and Matt Armitage explore the complicated relationship between the technologies of tomorrow and the legacy systems that play an outsize role in maintaining the world of today.

Following an ‘app for that’ side quest, they take a quick look at COBOL, the 60-year-old programming language that underpins global trade and explore the surprising volume of legacy code, systems and technologies that keep our high-tech world moving. From Python to energy grids to industrial control systems, ageing systems are reliably and efficiently resisting calls for their replacement.