LispLanguage programmers were probably the first "agile developers" on the planet, because as far back as the mid-60s, many of the practices that we know today as "agile practices" or even "ExtremeProgramming" were already in practice -- MikeBeedle
The HistoryOfExtremeProgramming acknowledges SeymourPapert's and AlanKay's contributions and therefore (indirectly) Lisp's.
A ForthVsLisp digression, but see also ForthValues.
Lisp (3rd ed.) by Winston and Horn, sometime between 1980 and 1988:
"Applications programming: Talented programmers find that Lisp can increase their productivity enormously, enabling them to write big programs much faster and far less expensively. This can have dramatic effects on the way big programs are developed. The old way was to start with multiyear periods of specification, followed by multiyear periods of implementation, leading to systems that produce disappointed, cranky users. The new way is to have prototypes up in a few months, with specification and implementation evolving together, with users constantly helping to shape the final results."
The Lisp Experience, Erik Sandewall, 1978:
For bottom-up program deveopment, it is desirable to be able to test procedures as they are developed. [...] The observed behavior of Lisp users indicates that top-down programming can be done not only using stepwise refinement, but often in a better way, through what has been called here structured growth, which is a relatively disciplined way of changing one's programs.
Incidentally, something else which might interest Lisp users from Winston & Horn:
"Systems programming. Lisp machines are high-powered workstations programmed from top to bottom in Lisp. The operating system, the user utility programs, the editors, the compilers, and the interpreters are all written in Lisp, demonstrating Lisp's power and versatility."
See also LispMachinesAreComingBack