In a large skillet with a lid, heat oil over medium high. Prick sausages all over with the tip of a knife and add to the skillet. Cook, turning occasionally, until browned on all sides, about 5 minutes. Transfer to a plate.
Add the onion, potatoes, caraway, and nutmeg to the skillet and season generously with salt and pepper. Cook, stirring often, until onions are softened, about 5 minutes. Add the beer and the bay leaf and bring to a simmer. Cover the skillet, reduce heat to medium, and simmer for 10 minutes.
Uncover the skillet and add the sauerkraut and apple juice. Nestle the sausages among the potatoes and sauerkraut and return skillet to a simmer. Cover and cook until potatoes are tender when pierced with a knife and sausages are just cooked through, about 5 minutes more.
Garnish with chives and serve with brown bread and mustard.
