Their proprietary securities database (called "SecDB" which actually is the internal name for all the quant analytics. The database itself is actually called a "SecServ") and it's associated programming language (called "Slang") are certainly very strange in many ways, but they do not predate the creation of C. In fact it was all written in C++ and Java and then more recently I think they added a bunch of Scala code.
Source: Was a "strat" (quant developer in the front office at Goldman) for 8 years, including starting in the group that used to run version repo, CI/CD pipeline and internal build and distribution tooling for all of this. Think a code pipeline that builds circa 30m lines of C++, 20-ishm lines of Java code daily on 3 different platforms (Linux, Solaris and Windows) and distributes it globally across thousands of machines every 2 weeks and if mistakes are made it can cost millions of USD. And this predates most of what people think of as "devops" by some years (I was there 2002-2010 ish).
Couple of fun facts to think about.
1)In any given 2 week release cycle (we didn't call them sprints) you would have just a bit shy of 700 individual devs checking in C++ or Java code.
2)The source code repo was CVS
I did the ports from pre-ansi to ansi C++ compilers on all three platforms (in each case with one other dev specific to the platform) and this was in the days when template instantiation compile error messages would be literally 50+ pages long. I got very good with vim and quickfix lists :-)
Maybe this is ridiculous but is there an ironic security upside in that? Systems become so old and increasingly proprietary, only a few people can make ends meat of it so fewer people would try and penetrate them? (I am not an engineer)
Source: Was a "strat" (quant developer in the front office at Goldman) for 8 years, including starting in the group that used to run version repo, CI/CD pipeline and internal build and distribution tooling for all of this. Think a code pipeline that builds circa 30m lines of C++, 20-ishm lines of Java code daily on 3 different platforms (Linux, Solaris and Windows) and distributes it globally across thousands of machines every 2 weeks and if mistakes are made it can cost millions of USD. And this predates most of what people think of as "devops" by some years (I was there 2002-2010 ish).