In this paper we answer the following well-known open question in computable model theory. Does there exist a computable not ‮א‬₀-categorical saturated structure with a unique computable isomorphism type? Our answer is affirmative and uses a construction based on Kolmogorov complexity. With a variation of this construction, we also provide an example of an ‮א‬₁-categorical but not ‮א‬₀-categorical saturated $\Sigma _{1}^{0}$ -structure with a unique computable isomorphism type. In addition, using the construction we give an example of an ‮א‬₁-categorical but (...) not ‮א‬₁-categorical theory whose only non-computable model is the prime one. (shrink)