diff --git a/core/block_validator.go b/core/block_validator.go
index 59783a0407..a3306365cc 100644
--- a/core/block_validator.go
+++ b/core/block_validator.go
@@ -93,7 +93,7 @@ func (v *BlockValidator) ValidateBody(block *types.Block) error {
 		}
 
 		// The individual checks for blob validity (version-check + not empty)
-		// happens in StateTransition.
+		// happens in stateTransition.
 	}
 
 	// Check blob gas usage.
diff --git a/core/state_transition.go b/core/state_transition.go
index cb7d71efcb..d397a57844 100644
--- a/core/state_transition.go
+++ b/core/state_transition.go
@@ -189,10 +189,10 @@ func TransactionToMessage(tx *types.Transaction, s types.Signer, baseFee *big.In
 func ApplyMessage(evm *vm.EVM, msg *Message, gp *GasPool) (*ExecutionResult, error) {
 	evm.SetTxContext(NewEVMTxContext(msg))
 
-	return NewStateTransition(evm, msg, gp).TransitionDb()
+	return newStateTransition(evm, msg, gp).execute()
 }
 
-// StateTransition represents a state transition.
+// stateTransition represents a state transition.
 //
 // == The State Transitioning Model
 //
@@ -214,7 +214,7 @@ func ApplyMessage(evm *vm.EVM, msg *Message, gp *GasPool) (*ExecutionResult, err
 //
 //  5. Run Script section
 //  6. Derive new state root
-type StateTransition struct {
+type stateTransition struct {
 	gp           *GasPool
 	msg          *Message
 	gasRemaining uint64
@@ -223,9 +223,9 @@ type StateTransition struct {
 	evm          *vm.EVM
 }
 
-// NewStateTransition initialises and returns a new state transition object.
-func NewStateTransition(evm *vm.EVM, msg *Message, gp *GasPool) *StateTransition {
-	return &StateTransition{
+// newStateTransition initialises and returns a new state transition object.
+func newStateTransition(evm *vm.EVM, msg *Message, gp *GasPool) *stateTransition {
+	return &stateTransition{
 		gp:    gp,
 		evm:   evm,
 		msg:   msg,
@@ -234,14 +234,14 @@ func NewStateTransition(evm *vm.EVM, msg *Message, gp *GasPool) *StateTransition
 }
 
 // to returns the recipient of the message.
-func (st *StateTransition) to() common.Address {
+func (st *stateTransition) to() common.Address {
 	if st.msg == nil || st.msg.To == nil /* contract creation */ {
 		return common.Address{}
 	}
 	return *st.msg.To
 }
 
-func (st *StateTransition) buyGas() error {
+func (st *stateTransition) buyGas() error {
 	mgval := new(big.Int).SetUint64(st.msg.GasLimit)
 	mgval.Mul(mgval, st.msg.GasPrice)
 	balanceCheck := new(big.Int).Set(mgval)
@@ -285,7 +285,7 @@ func (st *StateTransition) buyGas() error {
 	return nil
 }
 
-func (st *StateTransition) preCheck() error {
+func (st *stateTransition) preCheck() error {
 	// Only check transactions that are not fake
 	msg := st.msg
 	if !msg.SkipNonceChecks {
@@ -370,7 +370,7 @@ func (st *StateTransition) preCheck() error {
 	return st.buyGas()
 }
 
-// TransitionDb will transition the state by applying the current message and
+// execute will transition the state by applying the current message and
 // returning the evm execution result with following fields.
 //
 //   - used gas: total gas used (including gas being refunded)
@@ -380,7 +380,7 @@ func (st *StateTransition) preCheck() error {
 //
 // However if any consensus issue encountered, return the error directly with
 // nil evm execution result.
-func (st *StateTransition) TransitionDb() (*ExecutionResult, error) {
+func (st *stateTransition) execute() (*ExecutionResult, error) {
 	// First check this message satisfies all consensus rules before
 	// applying the message. The rules include these clauses
 	//
@@ -495,7 +495,7 @@ func (st *StateTransition) TransitionDb() (*ExecutionResult, error) {
 	}, nil
 }
 
-func (st *StateTransition) refundGas(refundQuotient uint64) uint64 {
+func (st *stateTransition) refundGas(refundQuotient uint64) uint64 {
 	// Apply refund counter, capped to a refund quotient
 	refund := st.gasUsed() / refundQuotient
 	if refund > st.state.GetRefund() {
@@ -525,11 +525,11 @@ func (st *StateTransition) refundGas(refundQuotient uint64) uint64 {
 }
 
 // gasUsed returns the amount of gas used up by the state transition.
-func (st *StateTransition) gasUsed() uint64 {
+func (st *stateTransition) gasUsed() uint64 {
 	return st.initialGas - st.gasRemaining
 }
 
 // blobGasUsed returns the amount of blob gas used by the message.
-func (st *StateTransition) blobGasUsed() uint64 {
+func (st *stateTransition) blobGasUsed() uint64 {
 	return uint64(len(st.msg.BlobHashes) * params.BlobTxBlobGasPerBlob)
 }