It's hard to get a super compact eval for LISP with its many primitives. It's somewhat easier for the lambda calculus which inspired LISP, with obnly the 3 primitives of variable, abstraction, and application. In the binary lambda calculus this allows for a self-interpreter

    (λ 1 1) (λ λ λ 1 (λ λ λ λ 3 (λ 5 (3 (λ 2 (3 (λ λ 3 (λ 1 2 3))) (4 (λ 4
    (λ 3 1 (2 1)))))) (1 (2 (λ 1 2)) (λ 4 (λ 4 (λ 2 (1 4))) 5)))) (3 3) 2)

[1] https://tromp.github.io/cl/cl.html