Taming Complexity: Building and Deploying a 270 KLOC Integrated Scientific Application in Common Lisp

This paper examines strategies for managing a 270 KLOC
Common Lisp monorepo dedicated to computational fluid
dynamics and stochastic optimization. By leveraging CLOS,
Macros, and REPL-driven development, we addressed the
”crisis of scale” inherent in 1,400 source files. To optimize
cloud-native delivery, we implemented a tiered three-phase
build strategy, reducing build latency by 33–53%. Further-
more, refactoring deployment logic achieved an 8x speedup
in Kubernetes manifest synchronization. Our findings demon-
strate that Common Lisp, combined with disciplined modu-
larity, build optimization, and modern DevOps, provides a
highly effective foundation for large-scale applications.