diff --git a/include/fractal.hpp b/include/fractal.hpp
index cec7352..601b5e6 100644
--- a/include/fractal.hpp
+++ b/include/fractal.hpp
@@ -16,6 +16,8 @@ constexpr size_t g_max_branch_rules = 8;
 constexpr size_t g_max_mark_rules = 4;
 constexpr size_t g_max_cgroup_tokens = 16;
 constexpr size_t g_max_wgroup_weights = 8;
+constexpr size_t g_max_match_groups = 8;
+constexpr size_t g_max_match_wgroups = 4;
 
 using token_id_t = uint32_t;
 using group_id_t = uint32_t;
@@ -56,7 +58,7 @@ struct weighted_leaf_t {
 	mtl::mat<2, 2> m_orientation;
 };
 
-struct group_t {
+struct group_output_t {
 	static constexpr size_t g_max_child_leafs = 16;
 	static constexpr size_t g_max_child_markers = 8;
 
@@ -64,6 +66,11 @@ struct group_t {
 	etl::vector<marker_t, g_max_child_markers> m_child_markers;
 };
 
+struct token_match_t {
+	etl::vector<group_id_t, g_max_match_groups> m_groups;
+	etl::vector<weighted_group_id_t, g_max_match_wgroups> m_wgroups;
+};
+
 struct weighted_group_t {
 	etl::vector<group_id_t, g_max_wgroup_weights> m_groups;
 	etl::vector<uint32_t, g_max_wgroup_weights> m_weights;
@@ -239,6 +246,38 @@ public:
 	mark_rule_id_t add_mark_rule(token_id_t match, uint32_t tag);
 };
 
+class generator_t {
+	etl::vector<weighted_group_t, g_max_wgroups> m_weighted_groups;
+	etl::vector<group_output_t, g_max_groups> m_group_outputs;
+	etl::vector<token_match_t, g_max_tokens> m_token_matches;
+	group_id_t m_axiom;
+
+	uint32_t m_gen_num;
+
+public:
+	generator_t(const ruleset_t& ruleset);
+
+	/**
+	 * @brief Steps one generation, outputting generated markers
+	 *
+	 * @tparam CONTAINER_T  Container type of @c marker_t that supplies an @c insert member
+	 * function taking an iterator and value, @c size , and @c max_size functions
+	 *
+	 * @param out_markers   Reference to a container to append generated markers to
+	 * 
+	 * @ret false if there is not enough room for the child leafs (internally)
+	 * or there is not enough room for the generated markers in @p out_markers, true otherwise
+	 *
+	 * Steps one generation of the fractal, and appends any child markers of
+	 * the current generation to @p out_markers. If there is not enough room
+	 * for all of the child markers, @p out_markers is unmodified. 
+	 */
+	template <typename CONTAINER_T>
+	bool step_generation(CONTAINER_T& out_markers);
+
+	uint32_t generation_num() const { return m_gen_num; }
+};
+
 #if 0
 class generator_t {
 private:
diff --git a/src/main.cpp b/src/main.cpp
index 96baa8f..a9f43cb 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -58,6 +58,17 @@ int main(void) {
 		return 0;
 	}
 
+	generator_t gen(rules);
+	etl::vector<marker_t, 100> output;
+
+	while (gen.step_generation(output)) {
+		log::debug << "Stepped generation" << gen.generation_num() << endl;
+
+		for (const marker_t& m : output) {
+			log::debug << ' ' << m.m_id << ", " << m.m_pos << endl;
+		}
+	}
+
 	while (true) {
 		vid_vsync();
 	}