diff --git a/libs/pcg/include/psemek/pcg/lazy_perlin.hpp b/libs/pcg/include/psemek/pcg/lazy_perlin.hpp
index d99d0b25..e4e65a52 100644
--- a/libs/pcg/include/psemek/pcg/lazy_perlin.hpp
+++ b/libs/pcg/include/psemek/pcg/lazy_perlin.hpp
@@ -14,6 +14,9 @@ namespace psemek::pcg
 	{
 		using generator_func = util::function<geom::vector<T, N>(geom::vector<int, N> const &)>;
 
+		using value_type = T;
+		static constexpr auto dimension = N;
+
 		lazy_perlin (std::size_t grid_size, generator_func generator)
 			: grid_size_(grid_size)
 			, gen_(std::move(generator))