diff --git a/gemma/common.h b/gemma/common.h
index e5a581e..f234786 100644
--- a/gemma/common.h
+++ b/gemma/common.h
@@ -36,7 +36,12 @@ ByteStorageT AllocateSizeof() {
 }
 
 // Model variants: see configs.h for details.
-enum class Model { GEMMA_2B, GEMMA_7B, GRIFFIN_2B, GEMMA_TINY };
+enum class Model {
+  GEMMA_2B,
+  GEMMA_7B,
+  GRIFFIN_2B,
+  GEMMA_TINY,
+};
 
 // Instruction-tuned models require extra 'turn structure' tokens in prompts.
 enum class ModelTraining { GEMMA_IT, GEMMA_PT };
diff --git a/gemma/configs.h b/gemma/configs.h
index fb4231a..b59b450 100644
--- a/gemma/configs.h
+++ b/gemma/configs.h
@@ -73,8 +73,18 @@ constexpr size_t NumLayersOfTypeBefore(
   return count;
 }
 
+struct ConfigNoSSM {
+  static constexpr int kConv1dWidth = 0;
+  static constexpr bool kFFBiases = false;
+  static constexpr bool kSoftmaxAttnOutputBiases = false;
+  static constexpr bool kUseHalfRope = false;
+  static constexpr bool kUseLocalAttention = false;
+  static constexpr bool kInterleaveQKV = true;
+  static constexpr int kNumTensorScales = 0;
+};
+
 template <typename TWeight>
-struct ConfigGemma7B {
+struct ConfigGemma7B : public ConfigNoSSM {
   using Weight = TWeight;  // make accessible where we only have a TConfig
 
   static constexpr int kSeqLen = gcpp::kSeqLen;
@@ -96,19 +106,10 @@ struct ConfigGemma7B {
   static constexpr int kTopK = gcpp::kTopK;
   static constexpr bool kAbsolutePE = false;
   static constexpr bool kPostNormScale = false;
-
-  // SSM config.
-  static constexpr int kConv1dWidth = 0;
-  static constexpr bool kFFBiases = false;
-  static constexpr bool kSoftmaxAttnOutputBiases = false;
-  static constexpr bool kUseHalfRope = false;
-  static constexpr bool kUseLocalAttention = false;
-  static constexpr bool kInterleaveQKV = true;
-  static constexpr int kNumTensorScales = 0;
 };
 
 template <typename TWeight>
-struct ConfigGemma2B {
+struct ConfigGemma2B : public ConfigNoSSM {
   using Weight = TWeight;  // make accessible where we only have a TConfig
 
   static constexpr int kSeqLen = gcpp::kSeqLen;
@@ -118,10 +119,8 @@ struct ConfigGemma2B {
   static constexpr int kLayers = kLayerConfig.size();
   static constexpr int kGemmaLayers =
       NumLayersOfTypeBefore(kLayerConfig, LayerAttentionType::kGemma, kLayers);
-  static constexpr int kGriffinLayers =
-      NumLayersOfTypeBefore(kLayerConfig,
-                            LayerAttentionType::kGriffinRecurrentBlock,
-                            kLayers);
+  static constexpr int kGriffinLayers = NumLayersOfTypeBefore(
+      kLayerConfig, LayerAttentionType::kGriffinRecurrentBlock, kLayers);
   static constexpr int kModelDim = 2048;
   static constexpr int kFFHiddenDim = 16 * 2048 / 2;  // = 16384
   static constexpr int kHeads = 8;
@@ -130,19 +129,10 @@ struct ConfigGemma2B {
   static constexpr int kTopK = gcpp::kTopK;
   static constexpr bool kAbsolutePE = false;
   static constexpr bool kPostNormScale = false;
-
-  // SSM config.
-  static constexpr int kConv1dWidth = 0;
-  static constexpr bool kFFBiases = false;
-  static constexpr bool kSoftmaxAttnOutputBiases = false;
-  static constexpr bool kUseHalfRope = false;
-  static constexpr bool kUseLocalAttention = false;
-  static constexpr bool kInterleaveQKV = true;
-  static constexpr int kNumTensorScales = 0;
 };
 
 template <typename TWeight>
-struct ConfigGemmaTiny {
+struct ConfigGemmaTiny : public ConfigNoSSM {
   using Weight = TWeight;  // make accessible where we only have a TConfig
 
   static constexpr int kSeqLen = 32;
@@ -164,15 +154,6 @@ struct ConfigGemmaTiny {
   static constexpr int kTopK = gcpp::kTopK;
   static constexpr bool kAbsolutePE = false;
   static constexpr bool kPostNormScale = false;
-
-  // SSM config.
-  static constexpr int kConv1dWidth = 0;
-  static constexpr bool kFFBiases = false;
-  static constexpr bool kSoftmaxAttnOutputBiases = false;
-  static constexpr bool kUseHalfRope = false;
-  static constexpr bool kUseLocalAttention = false;
-  static constexpr bool kInterleaveQKV = true;
-  static constexpr int kNumTensorScales = 0;
 };
 
 template <typename TWeight>