Haven’t worked with buckwheat yet in my breads, but it makes the most aMAZING crepes and pancakes! I made pear and walnut pancakes on the weekend with equal amounts unbleached AP, buckwheat flour and sourdough starter that I let “work” for about an hour before adding the other ingredients. Yum!
Despite its name, it’s not actually a wheat. Not even a cereal grain. However, it shares many properties with cereal grain kernels, so is often ground into flour or grits. Roasted kernels are called kasha. You may have seen that. Because of its strong, distinct flavour, dark colour - and most important re: your question, lack of gluten - buckwheat flour is typically used in combination with wheat flour. The usual ratio is one-quarter to one-half buckwheat flour to one part wheat flour.
It would be interesting to try buckwheat as a flavour addition to Rose’s hearth bread recipe. You’d love the breakfast bread options too! Russian pancakes (blini) are traditionally made from buckwheat, as are Breton crepes from the north of France. I’m also mad about the Japanese buckwheat noodles called soba. Wonderful flavour and very good for you.