Interesting, I tried to convert Z combinator in SKI to this using the lambda calculus example then print out the tree. Untested:
z = (t (t (t t (t (t (t (t (t t (t (t (t (t (t t)) (t t))) (t (t (t t)) (t t))))) (t (t (t t (t (t (t t (t (t (t t t)) t))) (t t)))) (t (t (t t (t (t (t (t (t t)) (t t)))))) (t t))))) (t t (t (t (t (t (t t))))))))) (t (t (t (t (t t (t (t (t (t (t t (t (t (t t (t (t (t t t)) t))) (t t)))) (t (t (t t t)) t))) (t t (t t))))) (t (t (t t (t (t (t (t (t t (t (t (t t (t (t (t t t)) t))) (t t)))) (t (t (t t t)) t))) (t t (t t))))) (t (t (t t (t (t (t t t)) t))) (t t))))) (t t (t (t (t (t (t t (t (t (t (t (t t)) (t t))) (t (t (t t)) (t t))))) (t (t (t t (t (t (t t (t (t (t t t)) t))) (t t)))) (t (t (t t (t (t (t (t (t t)) (t t)))))) (t t))))) (t t (t (t (t t (t (t (t (t (t t (t (t (t (t (t t (t (t (t t (t (t (t t t)) t))) (t t)))) (t (t (t t t)) t))) (t t (t t))))) (t (t (t t (t (t (t (t (t t (t (t (t t (t (t (t t t)) t))) (t t)))) (t (t (t t t)) t))) (t t (t t))))) (t (t (t t (t (t (t (t (t t)) (t t)))))) (t t)))))))) (t t)))))))
Original tested but unoptimized and also converted using tool:
var K = a => b => a;
var S = a => b => c => a(c)(b(c));
var Z = S(K(S(S(K(S(S(K)(K))(S(K)(K))))(S(K(S(K(S))(K)))(S(K(S(S(K)(K))))(K))))(K(S(S(K))))))(S(S(K(S(S(K(S(K(S))(K)))(S))(K(K))))(S(K(S(S(K(S(K(S))(K)))(S))(K(K))))(S(K(S))(K))))(K(S(S(K(S(S(K)(K))(S(K)(K))))(S(K(S(K(S))(K)))(S(K(S(S(K)(K))))(K))))(K(S(K(S(S(K(S(S(K(S(K(S))(K)))(S))(K(K))))(S(K(S(S(K(S(K(S))(K)))(S))(K(K))))(S(K(S(S(K)(K))))(K))))))(K))))));
Any source code in any programming language can in theory be encoded in unary, requiring only a single symbol (and without any need for extra grouping or whitespace). It's not gonna be efficient, though.
Yeah, I think I'm going to take the author's advice and use Tree Calculus to generate JSON config files. That way I won't need to use a bloated tool with a JSON parser just to output configuration.
Z = \f. (\x. f (\v. x x v)) (\x. f (\v. x x v)) can be much simpler, namely
S (S (K (S S (K (S (S K K) (S K K))))) K) (S (K (S S (K (S (S K K) (S K K))))) K)