Why care about programming languages

Summary

Eduardo's blog Why care about programming languages July 22, 2026 by Eduardo Bellani In the age of AI-assisted coding, it’s easy to feel that deep knowledge of programming languages has become obsolete. Why spend years mastering language intricacies when an AI can generate code in any language on demand? I recently encountered this sentiment in a question from a fellow developer: I feel like caring about programming languages and stuff is actually very useless. … Am I being too extreme? I understand the concern, but I believe it misses something fundamental: a programming language’s worth is derived from the ideas it embodies, not merely its syntax or tooling. These ideas—concepts about how to structure thought, manage complexity, and solve problems—remain essential regardless of who or what writes the code. Here is my sample list of deep ideas from programming languages: on Rust, the borrow checker—reasoning about ownership and lifetimes on Haskell, typeclasses—principled polymorphism and abstraction on SML/OCaml, the module system—large-scale program organization and decoupling on OOP languages, identity vs equality—understanding state and comparison on SQL, relational theory/algebra—declarative data manipulation on Prolog, first order predicate logic—logic-based problem solving on C, arrays and pointers—understanding memory layout and indirection on Lisp, syntax extensions—metaprogramming and language-oriented programming on functional languages, first class functions—treating computation as values on SML, Haskell and others, algebraic data types—modeling domains with types on Clojure, maps and immutable data structures—persistent data and structural sharing on OCaml, row polymorphism—static typing for extensible records Each of these concepts represents a different way of thinking about computation. Learning them expands your mental toolkit for solving problems. When you understand the borrow checker, you think differently about resource management everywhere. W...