diff --git a/types/application.go b/types/application.go
index bb9a0030d..f0ce18955 100644
--- a/types/application.go
+++ b/types/application.go
@@ -25,7 +25,57 @@ type Application interface {
 	Commit() ResponseCommit                          // Commit the state and return the application Merkle root hash
 }
 
-//------------------------------------
+//-------------------------------------------------------
+// BaseApplication is a base form of Application
+
+var _ Application = (*BaseApplication)(nil)
+
+type BaseApplication struct {
+}
+
+func NewBaseApplication() *BaseApplication {
+	return &BaseApplication{}
+}
+
+func (BaseApplication) Info(req RequestInfo) ResponseInfo {
+	return ResponseInfo{}
+}
+
+func (BaseApplication) SetOption(req RequestSetOption) ResponseSetOption {
+	return ResponseSetOption{}
+}
+
+func (BaseApplication) DeliverTx(tx []byte) ResponseDeliverTx {
+	return ResponseDeliverTx{Code: CodeTypeOK}
+}
+
+func (BaseApplication) CheckTx(tx []byte) ResponseCheckTx {
+	return ResponseCheckTx{Code: CodeTypeOK}
+}
+
+func (BaseApplication) Commit() ResponseCommit {
+	return ResponseCommit{Code: CodeTypeOK}
+}
+
+func (BaseApplication) Query(req RequestQuery) ResponseQuery {
+	return ResponseQuery{Code: CodeTypeOK}
+}
+
+func (BaseApplication) InitChain(req RequestInitChain) ResponseInitChain {
+	return ResponseInitChain{}
+}
+
+func (BaseApplication) BeginBlock(req RequestBeginBlock) ResponseBeginBlock {
+	return ResponseBeginBlock{}
+}
+
+func (BaseApplication) EndBlock(req RequestEndBlock) ResponseEndBlock {
+	return ResponseEndBlock{}
+}
+
+//-------------------------------------------------------
+
+var _ Application = (*GRPCApplication)(nil)
 
 // GRPCApplication is a GRPC wrapper for Application
 type GRPCApplication struct {
diff --git a/types/base_app.go b/types/base_app.go
deleted file mode 100644
index 1998e9dcb..000000000
--- a/types/base_app.go
+++ /dev/null
@@ -1,44 +0,0 @@
-package types
-
-type BaseApplication struct {
-}
-
-func NewBaseApplication() *BaseApplication {
-	return &BaseApplication{}
-}
-
-func (BaseApplication) Info(req RequestInfo) ResponseInfo {
-	return ResponseInfo{}
-}
-
-func (BaseApplication) SetOption(req RequestSetOption) ResponseSetOption {
-	return ResponseSetOption{}
-}
-
-func (BaseApplication) DeliverTx(tx []byte) ResponseDeliverTx {
-	return ResponseDeliverTx{Code: CodeTypeOK}
-}
-
-func (BaseApplication) CheckTx(tx []byte) ResponseCheckTx {
-	return ResponseCheckTx{Code: CodeTypeOK}
-}
-
-func (BaseApplication) Commit() ResponseCommit {
-	return ResponseCommit{Code: CodeTypeOK}
-}
-
-func (BaseApplication) Query(req RequestQuery) ResponseQuery {
-	return ResponseQuery{Code: CodeTypeOK}
-}
-
-func (BaseApplication) InitChain(req RequestInitChain) ResponseInitChain {
-	return ResponseInitChain{}
-}
-
-func (BaseApplication) BeginBlock(req RequestBeginBlock) ResponseBeginBlock {
-	return ResponseBeginBlock{}
-}
-
-func (BaseApplication) EndBlock(req RequestEndBlock) ResponseEndBlock {
-	return ResponseEndBlock{}
-}
diff --git a/types/kvpair.go b/types/kvpair.go
deleted file mode 100644
index c7aad4407..000000000
--- a/types/kvpair.go
+++ /dev/null
@@ -1,19 +0,0 @@
-package types
-
-// KVPairInt is a helper method to build KV pair with an integer value.
-func KVPairInt(key string, val int64) *KVPair {
-	return &KVPair{
-		Key:       key,
-		ValueInt:  val,
-		ValueType: KVPair_INT,
-	}
-}
-
-// KVPairString is a helper method to build KV pair with a string value.
-func KVPairString(key, val string) *KVPair {
-	return &KVPair{
-		Key:         key,
-		ValueString: val,
-		ValueType:   KVPair_STRING,
-	}
-}
diff --git a/types/validators.go b/types/util.go
similarity index 60%
rename from types/validators.go
rename to types/util.go
index 6bbe3f847..17c53f659 100644
--- a/types/validators.go
+++ b/types/util.go
@@ -8,6 +8,8 @@ import (
 	cmn "github.com/tendermint/tmlibs/common"
 )
 
+//------------------------------------------------------------------------------
+
 // Validators is a list of validators that implements the Sort interface
 type Validators []*Validator
 
@@ -26,13 +28,6 @@ func (v Validators) Swap(i, j int) {
 	v[j] = v1
 }
 
-//-------------------------------------
-
-type validatorPretty struct {
-	PubKey data.Bytes `json:"pub_key"`
-	Power  int64      `json:"power"`
-}
-
 func ValidatorsString(vs Validators) string {
 	s := make([]validatorPretty, len(vs))
 	for i, v := range vs {
@@ -44,3 +39,28 @@ func ValidatorsString(vs Validators) string {
 	}
 	return string(b)
 }
+
+type validatorPretty struct {
+	PubKey data.Bytes `json:"pub_key"`
+	Power  int64      `json:"power"`
+}
+
+//------------------------------------------------------------------------------
+
+// KVPairInt is a helper method to build KV pair with an integer value.
+func KVPairInt(key string, val int64) *KVPair {
+	return &KVPair{
+		Key:       key,
+		ValueInt:  val,
+		ValueType: KVPair_INT,
+	}
+}
+
+// KVPairString is a helper method to build KV pair with a string value.
+func KVPairString(key, val string) *KVPair {
+	return &KVPair{
+		Key:         key,
+		ValueString: val,
+		ValueType:   KVPair_STRING,
+	}
+}
diff --git a/types/kvpair_test.go b/types/util_test.go
similarity index 100%
rename from types/kvpair_test.go
rename to types/util_test.go