What is break-even point (programming)?
A programming language should reach a 'break-even point' if it can be implemented by itself. For example a Lisp interpreter, which is also written in Lisp. A primary goal for a new programming language is to break even as it is easier to send programming tools out when they are not dependent on another language.
The breakeven point is when a programming language can be implemented in the programming language itself. For example, a C compiler could compile its own C source code. New programming languages are often written in an existing language. When the break-even point is reached, a developer can ignore the original implementation and focus on developing a new language.
Lisp is famous for its ability to reimplement itself. A Lisp compiler written in Lisp was developed at MIT in 1962. Many other programming languages have reached break-even point.