The a16z Show · Monday, July 13, 2026
Barbara Liskov described her work on the Argus programming language, which extended her previous language, Clue, by introducing 'guardians' for distributed systems. These guardians, residing on network nodes, enabled operations to be called from other nodes, forming distributed programs.
“And in Argus, which was the new language, we had abstract data types and then we had one additional feature, this new kind of object which we called a guardian.”
“And the idea with the guardian was it resided at one node of the network. It provided operations that could be called from other nodes.”
“And so the idea was a distributed program consists of all these guardians, each running on its node, communicating with each other.”