diff --git a/cl/cltypes/aggregate.go b/cl/cltypes/aggregate.go
index 4c7bcb5b9..c6c8e6694 100644
--- a/cl/cltypes/aggregate.go
+++ b/cl/cltypes/aggregate.go
@@ -57,8 +57,8 @@ func (a *SignedAggregateAndProof) EncodingSizeSSZ() int {
  * and signature is the aggregate BLS signature of the committee.
  */
 type SyncAggregate struct {
-	SyncCommiteeBits      [64]byte
-	SyncCommiteeSignature [96]byte
+	SyncCommiteeBits      [64]byte          `json:"sync_commitee_bits"`
+	SyncCommiteeSignature libcommon.Bytes96 `json:"signature"`
 }
 
 // return sum of the committee bits
diff --git a/cl/cltypes/beacon_block.go b/cl/cltypes/beacon_block.go
index 2f6a266f8..818e6d376 100644
--- a/cl/cltypes/beacon_block.go
+++ b/cl/cltypes/beacon_block.go
@@ -23,46 +23,46 @@ const (
 )
 
 type SignedBeaconBlock struct {
-	Signature libcommon.Bytes96
-	Block     *BeaconBlock
+	Signature libcommon.Bytes96 `json:"signature"`
+	Block     *BeaconBlock      `json:"message"`
 }
 
 type BeaconBlock struct {
-	Slot          uint64
-	ProposerIndex uint64
-	ParentRoot    libcommon.Hash
-	StateRoot     libcommon.Hash
-	Body          *BeaconBody
+	Slot          uint64         `json:"slot"`
+	ProposerIndex uint64         `json:"proposer_index"`
+	ParentRoot    libcommon.Hash `json:"parent_root"`
+	StateRoot     libcommon.Hash `json:"state_root"`
+	Body          *BeaconBody    `json:"body"`
 }
 
 type BeaconBody struct {
 	// A byte array used for randomness in the beacon chain
-	RandaoReveal libcommon.Bytes96
+	RandaoReveal libcommon.Bytes96 `json:"randao_reveal"`
 	// Data related to the Ethereum 1.0 chain
-	Eth1Data *Eth1Data
+	Eth1Data *Eth1Data `json:"eth1_data"`
 	// A byte array used to customize validators' behavior
-	Graffiti libcommon.Hash
+	Graffiti libcommon.Hash `json:"graffit"`
 	// A list of slashing events for validators who included invalid blocks in the chain
-	ProposerSlashings *solid.ListSSZ[*ProposerSlashing]
+	ProposerSlashings *solid.ListSSZ[*ProposerSlashing] `json:"proposer_slashings"`
 	// A list of slashing events for validators who included invalid attestations in the chain
-	AttesterSlashings *solid.ListSSZ[*AttesterSlashing]
+	AttesterSlashings *solid.ListSSZ[*AttesterSlashing] `json:"attester_slashings"`
 	// A list of attestations included in the block
-	Attestations *solid.ListSSZ[*solid.Attestation]
+	Attestations *solid.ListSSZ[*solid.Attestation] `json:"attestations"`
 	// A list of deposits made to the Ethereum 1.0 chain
-	Deposits *solid.ListSSZ[*Deposit]
+	Deposits *solid.ListSSZ[*Deposit] `json:"deposits"`
 	// A list of validators who have voluntarily exited the beacon chain
-	VoluntaryExits *solid.ListSSZ[*SignedVoluntaryExit]
+	VoluntaryExits *solid.ListSSZ[*SignedVoluntaryExit] `json:"voluntary_exits"`
 	// A summary of the current state of the beacon chain
-	SyncAggregate *SyncAggregate
+	SyncAggregate *SyncAggregate `json:"sync_aggregate,omitempty"`
 	// Data related to crosslink records and executing operations on the Ethereum 2.0 chain
-	ExecutionPayload *Eth1Block
+	ExecutionPayload *Eth1Block `json:"execution_payload,omitempty"`
 	// Withdrawals Diffs for Execution Layer
-	ExecutionChanges *solid.ListSSZ[*SignedBLSToExecutionChange]
+	ExecutionChanges *solid.ListSSZ[*SignedBLSToExecutionChange] `json:"execution_changes,omitempty"`
 	// The commitments for beacon chain blobs
 	// With a max of 4 per block
-	BlobKzgCommitments *solid.ListSSZ[*KZGCommitment]
+	BlobKzgCommitments *solid.ListSSZ[*KZGCommitment] `json:"blob_kzg_commitments,omitempty"`
 	// The version of the beacon chain
-	Version   clparams.StateVersion
+	Version   clparams.StateVersion `json:"-"`
 	beaconCfg *clparams.BeaconChainConfig
 }
 
diff --git a/cl/cltypes/beacon_kzgcommitment.go b/cl/cltypes/beacon_kzgcommitment.go
index 7b42d0b3b..f6a5d5f38 100644
--- a/cl/cltypes/beacon_kzgcommitment.go
+++ b/cl/cltypes/beacon_kzgcommitment.go
@@ -1,7 +1,10 @@
 package cltypes
 
 import (
+	"encoding/json"
+
 	gokzg4844 "github.com/crate-crypto/go-kzg-4844"
+	libcommon "github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon/cl/merkle_tree"
 	ssz2 "github.com/ledgerwatch/erigon/cl/ssz"
 )
@@ -16,6 +19,14 @@ const BYTES_PER_BLOB = uint64(BYTES_PER_FIELD_ELEMENT * FIELD_ELEMENTS_PER_BLOB)
 
 type KZGCommitment gokzg4844.KZGCommitment
 
+func (b KZGCommitment) MarshalJSON() ([]byte, error) {
+	return json.Marshal(libcommon.Bytes48(b))
+}
+
+func (b *KZGCommitment) UnmarshalJSON(data []byte) error {
+	return json.Unmarshal(data, (*libcommon.Bytes48)(b))
+}
+
 func (b *KZGCommitment) Copy() *KZGCommitment {
 	copy := *b
 	return &copy
diff --git a/cl/cltypes/bls_to_execution_change.go b/cl/cltypes/bls_to_execution_change.go
index af9a0a027..676154f15 100644
--- a/cl/cltypes/bls_to_execution_change.go
+++ b/cl/cltypes/bls_to_execution_change.go
@@ -11,9 +11,9 @@ import (
 
 // Change to EL engine
 type BLSToExecutionChange struct {
-	ValidatorIndex uint64
-	From           libcommon.Bytes48
-	To             libcommon.Address
+	ValidatorIndex uint64            `json:"validator_index"`
+	From           libcommon.Bytes48 `json:"from"`
+	To             libcommon.Address `json:"to"`
 }
 
 func (b *BLSToExecutionChange) EncodeSSZ(buf []byte) ([]byte, error) {
@@ -43,8 +43,8 @@ func (*BLSToExecutionChange) Static() bool {
 }
 
 type SignedBLSToExecutionChange struct {
-	Message   *BLSToExecutionChange
-	Signature libcommon.Bytes96
+	Message   *BLSToExecutionChange `json:"message"`
+	Signature libcommon.Bytes96     `json:"signature"`
 }
 
 func (s *SignedBLSToExecutionChange) EncodeSSZ(buf []byte) ([]byte, error) {
diff --git a/cl/cltypes/eth1_block.go b/cl/cltypes/eth1_block.go
index 13dd43edf..f9009fe7a 100644
--- a/cl/cltypes/eth1_block.go
+++ b/cl/cltypes/eth1_block.go
@@ -16,24 +16,24 @@ import (
 
 // ETH1Block represents a block structure CL-side.
 type Eth1Block struct {
-	ParentHash    libcommon.Hash
-	FeeRecipient  libcommon.Address
-	StateRoot     libcommon.Hash
-	ReceiptsRoot  libcommon.Hash
-	LogsBloom     types.Bloom
-	PrevRandao    libcommon.Hash
-	BlockNumber   uint64
-	GasLimit      uint64
-	GasUsed       uint64
-	Time          uint64
-	Extra         *solid.ExtraData
-	BaseFeePerGas libcommon.Hash
+	ParentHash    libcommon.Hash    `json:"parent_hash"`
+	FeeRecipient  libcommon.Address `json:"fee_recipient"`
+	StateRoot     libcommon.Hash    `json:"state_root"`
+	ReceiptsRoot  libcommon.Hash    `json:"receipts_root"`
+	LogsBloom     types.Bloom       `json:"logs_bloom"`
+	PrevRandao    libcommon.Hash    `json:"prev_randao"`
+	BlockNumber   uint64            `json:"block_number"`
+	GasLimit      uint64            `json:"gas_limit"`
+	GasUsed       uint64            `json:"gas_used"`
+	Time          uint64            `json:"timestamp"`
+	Extra         *solid.ExtraData  `json:"extra_data"`
+	BaseFeePerGas libcommon.Hash    `json:"base_fee_per_gas"`
 	// Extra fields
-	BlockHash     libcommon.Hash
-	Transactions  *solid.TransactionsSSZ
-	Withdrawals   *solid.ListSSZ[*types.Withdrawal]
-	BlobGasUsed   uint64
-	ExcessBlobGas uint64
+	BlockHash     libcommon.Hash                    `json:"block_hash"`
+	Transactions  *solid.TransactionsSSZ            `json:"transactions"`
+	Withdrawals   *solid.ListSSZ[*types.Withdrawal] `json:"withdrawals,omitempty"`
+	BlobGasUsed   uint64                            `json:"blob_gas_used,omitempty"`
+	ExcessBlobGas uint64                            `json:"excess_blob_gas,omitempty"`
 	// internals
 	version   clparams.StateVersion
 	beaconCfg *clparams.BeaconChainConfig
diff --git a/cl/cltypes/eth1_data.go b/cl/cltypes/eth1_data.go
index 165560f8b..92b45be76 100644
--- a/cl/cltypes/eth1_data.go
+++ b/cl/cltypes/eth1_data.go
@@ -10,9 +10,9 @@ import (
 )
 
 type Eth1Data struct {
-	Root         libcommon.Hash
-	DepositCount uint64
-	BlockHash    libcommon.Hash
+	Root         libcommon.Hash `json:"deposit_root"`
+	DepositCount uint64         `json:"deposit_count"`
+	BlockHash    libcommon.Hash `json:"block_hash"`
 }
 
 func (e *Eth1Data) Copy() *Eth1Data {
diff --git a/cl/cltypes/indexed_attestation.go b/cl/cltypes/indexed_attestation.go
index b9eb1b0dc..e1690c0f7 100644
--- a/cl/cltypes/indexed_attestation.go
+++ b/cl/cltypes/indexed_attestation.go
@@ -11,9 +11,9 @@ import (
  * IndexedAttestation are attestantions sets to prove that someone misbehaved.
  */
 type IndexedAttestation struct {
-	AttestingIndices solid.Uint64ListSSZ
-	Data             solid.AttestationData
-	Signature        libcommon.Bytes96
+	AttestingIndices solid.Uint64ListSSZ   `json:"attesting_indicies"`
+	Data             solid.AttestationData `json:"data"`
+	Signature        libcommon.Bytes96     `json:"signature"`
 }
 
 func (i *IndexedAttestation) Static() bool {
diff --git a/cl/cltypes/slashings.go b/cl/cltypes/slashings.go
index 8a74b071a..f849b7b50 100644
--- a/cl/cltypes/slashings.go
+++ b/cl/cltypes/slashings.go
@@ -6,8 +6,8 @@ import (
 )
 
 type ProposerSlashing struct {
-	Header1 *SignedBeaconBlockHeader
-	Header2 *SignedBeaconBlockHeader
+	Header1 *SignedBeaconBlockHeader `json:"signed_header_1"`
+	Header2 *SignedBeaconBlockHeader `json:"signed_header_2"`
 }
 
 func (p *ProposerSlashing) EncodeSSZ(dst []byte) ([]byte, error) {
@@ -29,8 +29,8 @@ func (p *ProposerSlashing) HashSSZ() ([32]byte, error) {
 }
 
 type AttesterSlashing struct {
-	Attestation_1 *IndexedAttestation
-	Attestation_2 *IndexedAttestation
+	Attestation_1 *IndexedAttestation `json:"attestation_1"`
+	Attestation_2 *IndexedAttestation `json:"attestation_2"`
 }
 
 func (a *AttesterSlashing) EncodeSSZ(dst []byte) ([]byte, error) {
diff --git a/cl/cltypes/solid/attestation.go b/cl/cltypes/solid/attestation.go
index baf2354b3..12ca81b07 100644
--- a/cl/cltypes/solid/attestation.go
+++ b/cl/cltypes/solid/attestation.go
@@ -1,6 +1,10 @@
 package solid
 
 import (
+	"encoding/json"
+
+	libcommon "github.com/ledgerwatch/erigon-lib/common"
+	"github.com/ledgerwatch/erigon-lib/common/hexutility"
 	"github.com/ledgerwatch/erigon-lib/common/length"
 	"github.com/ledgerwatch/erigon-lib/types/clonable"
 	"github.com/ledgerwatch/erigon-lib/types/ssz"
@@ -44,6 +48,33 @@ func NewAttestionFromParameters(
 	return a
 }
 
+func (a Attestation) MarshalJSON() ([]byte, error) {
+	return json.Marshal(struct {
+		AggregationBits hexutility.Bytes
+		Signature       libcommon.Bytes96
+		Data            AttestationData
+	}{
+		AggregationBits: a.aggregationBitsBuffer,
+		Signature:       a.Signature(),
+		Data:            a.AttestantionData(),
+	})
+}
+
+func (a *Attestation) UnmarshalJSON(buf []byte) error {
+	var tmp struct {
+		AggregationBits hexutility.Bytes
+		Signature       libcommon.Bytes96
+		Data            AttestationData
+	}
+	if err := json.Unmarshal(buf, &tmp); err != nil {
+		return err
+	}
+	a.SetAggregationBits(tmp.AggregationBits)
+	a.SetSignature(tmp.Signature)
+	a.SetAttestationData(tmp.Data)
+	return nil
+}
+
 // AggregationBits returns the aggregation bits buffer of the Attestation instance.
 func (a *Attestation) AggregationBits() []byte {
 	return a.aggregationBitsBuffer
diff --git a/cl/cltypes/solid/attestation_data.go b/cl/cltypes/solid/attestation_data.go
index 65cad27b7..82cbebec8 100644
--- a/cl/cltypes/solid/attestation_data.go
+++ b/cl/cltypes/solid/attestation_data.go
@@ -3,6 +3,7 @@ package solid
 import (
 	"bytes"
 	"encoding/binary"
+	"encoding/json"
 
 	libcommon "github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon-lib/common/length"
@@ -37,6 +38,41 @@ func NewAttestionDataFromParameters(
 	return a
 }
 
+func (a AttestationData) MarshalJSON() ([]byte, error) {
+	return json.Marshal(struct {
+		Slot            uint64
+		Index           uint64
+		BeaconBlockRoot libcommon.Hash
+		Source          Checkpoint
+		Target          Checkpoint
+	}{
+		Slot:            a.Slot(),
+		BeaconBlockRoot: a.BeaconBlockRoot(),
+		Index:           a.ValidatorIndex(),
+		Source:          a.Source(),
+		Target:          a.Target(),
+	})
+}
+
+func (a AttestationData) UnmarshalJSON(buf []byte) error {
+	var tmp struct {
+		Slot            uint64
+		Index           uint64
+		BeaconBlockRoot libcommon.Hash
+		Source          Checkpoint
+		Target          Checkpoint
+	}
+	if err := json.Unmarshal(buf, &tmp); err != nil {
+		return err
+	}
+	a.SetSlot(tmp.Slot)
+	a.SetValidatorIndex(tmp.Index)
+	a.SetBeaconBlockRoot(tmp.BeaconBlockRoot)
+	a.SetSource(tmp.Source)
+	a.SetTarget(tmp.Target)
+	return nil
+}
+
 func NewAttestationData() AttestationData {
 	return make([]byte, attestationDataBufferSize)
 }
diff --git a/cl/cltypes/solid/checkpoint.go b/cl/cltypes/solid/checkpoint.go
index aa17c6019..66b1c96ad 100644
--- a/cl/cltypes/solid/checkpoint.go
+++ b/cl/cltypes/solid/checkpoint.go
@@ -3,6 +3,7 @@ package solid
 import (
 	"bytes"
 	"encoding/binary"
+	"encoding/json"
 
 	libcommon "github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon-lib/common/length"
@@ -32,6 +33,26 @@ func NewCheckpoint() Checkpoint {
 	return make([]byte, checkpointSize)
 }
 
+func (c Checkpoint) MarshalJSON() ([]byte, error) {
+	return json.Marshal(struct {
+		Epoch uint64
+		Root  libcommon.Hash
+	}{Epoch: c.Epoch(), Root: c.BlockRoot()})
+}
+
+func (c Checkpoint) UnmarshalJSON(buf []byte) error {
+	var tmp struct {
+		Epoch uint64
+		Root  libcommon.Hash
+	}
+	if err := json.Unmarshal(buf, &tmp); err != nil {
+		return err
+	}
+	c.SetEpoch(tmp.Epoch)
+	c.SetBlockRoot(tmp.Root)
+	return nil
+}
+
 // SetBlockRoot copies the given blockRoot into the correct location within the Checkpoint
 func (c Checkpoint) SetBlockRoot(blockRoot libcommon.Hash) {
 	copy(c[8:], blockRoot[:]) // copy the blockRoot into the Checkpoint starting at index 8
diff --git a/cl/cltypes/solid/extra_data.go b/cl/cltypes/solid/extra_data.go
index abaa04075..4ef2c78ec 100644
--- a/cl/cltypes/solid/extra_data.go
+++ b/cl/cltypes/solid/extra_data.go
@@ -2,8 +2,10 @@ package solid
 
 import (
 	"encoding/binary"
+	"encoding/json"
 
 	"github.com/ledgerwatch/erigon-lib/common"
+	"github.com/ledgerwatch/erigon-lib/common/hexutility"
 	"github.com/ledgerwatch/erigon-lib/common/length"
 	"github.com/ledgerwatch/erigon-lib/types/clonable"
 	"github.com/ledgerwatch/erigon/cl/merkle_tree"
@@ -22,6 +24,18 @@ func NewExtraData() *ExtraData {
 	}
 }
 
+func (e *ExtraData) UnmarshalJSON(buf []byte) error {
+	if err := json.Unmarshal(buf, (*hexutility.Bytes)(&e.data)); err != nil {
+		return err
+	}
+	e.l = len(e.data)
+	return nil
+}
+
+func (e ExtraData) MarshalJSON() ([]byte, error) {
+	return json.Marshal(hexutility.Bytes(e.data[:e.l]))
+}
+
 // Clone creates a new instance of ExtraData.
 func (*ExtraData) Clone() clonable.Clonable {
 	return NewExtraData()
diff --git a/cl/cltypes/solid/hash_list.go b/cl/cltypes/solid/hash_list.go
index bc6726784..35f430265 100644
--- a/cl/cltypes/solid/hash_list.go
+++ b/cl/cltypes/solid/hash_list.go
@@ -1,6 +1,8 @@
 package solid
 
 import (
+	"encoding/json"
+
 	"github.com/ledgerwatch/erigon-lib/common"
 	libcommon "github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon-lib/common/length"
@@ -23,6 +25,28 @@ func NewHashList(c int) HashListSSZ {
 	}
 }
 
+func (arr *hashList) MarshalJSON() ([]byte, error) {
+	list := make([]libcommon.Hash, arr.l)
+	for i := 0; i < arr.l; i++ {
+		list[0] = arr.Get(i)
+	}
+	return json.Marshal(list)
+}
+
+func (arr *hashList) UnmarshalJSON(buf []byte) error {
+	var list []libcommon.Hash
+
+	if err := json.Unmarshal(buf, &list); err != nil {
+		return err
+	}
+	arr.Clear()
+	arr.l = len(list)
+	for _, elem := range list {
+		arr.Append(elem)
+	}
+	return nil
+}
+
 func (h *hashList) Append(val libcommon.Hash) {
 	offset := h.l * length.Hash
 	if offset == len(h.u) {
diff --git a/cl/cltypes/solid/hash_vector.go b/cl/cltypes/solid/hash_vector.go
index 95f5fc3eb..e91642d7f 100644
--- a/cl/cltypes/solid/hash_vector.go
+++ b/cl/cltypes/solid/hash_vector.go
@@ -1,6 +1,8 @@
 package solid
 
 import (
+	"encoding/json"
+
 	libcommon "github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon-lib/common/length"
 	"github.com/ledgerwatch/erigon-lib/types/clonable"
@@ -26,6 +28,14 @@ func (h *hashVector) Append(val libcommon.Hash) {
 	panic("not implmented")
 }
 
+func (h hashVector) MarshalJSON() ([]byte, error) {
+	return json.Marshal(h.u)
+}
+
+func (h *hashVector) UnmarshalJSON(buf []byte) error {
+	return json.Unmarshal(buf, h.u)
+}
+
 func (h *hashVector) Cap() int {
 	return h.u.l
 }
diff --git a/cl/cltypes/solid/interfaces.go b/cl/cltypes/solid/interfaces.go
index b5373e20a..b6b42d2b0 100644
--- a/cl/cltypes/solid/interfaces.go
+++ b/cl/cltypes/solid/interfaces.go
@@ -1,6 +1,8 @@
 package solid
 
 import (
+	"encoding/json"
+
 	"github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon-lib/types/ssz"
 	ssz2 "github.com/ledgerwatch/erigon/cl/ssz"
@@ -23,7 +25,26 @@ type IterableSSZ[T any] interface {
 	ssz.HashableSSZ
 }
 
-type Uint64VectorSSZ IterableSSZ[uint64]
-type Uint64ListSSZ IterableSSZ[uint64]
-type HashListSSZ IterableSSZ[common.Hash]
-type HashVectorSSZ IterableSSZ[common.Hash]
+type Uint64ListSSZ interface {
+	IterableSSZ[uint64]
+	json.Marshaler
+	json.Unmarshaler
+}
+
+type Uint64VectorSSZ interface {
+	IterableSSZ[uint64]
+	json.Marshaler
+	json.Unmarshaler
+}
+
+type HashListSSZ interface {
+	IterableSSZ[common.Hash]
+	json.Marshaler
+	json.Unmarshaler
+}
+
+type HashVectorSSZ interface {
+	IterableSSZ[common.Hash]
+	json.Marshaler
+	json.Unmarshaler
+}
diff --git a/cl/cltypes/solid/list_ssz.go b/cl/cltypes/solid/list_ssz.go
index 11450d8f9..22234ebb8 100644
--- a/cl/cltypes/solid/list_ssz.go
+++ b/cl/cltypes/solid/list_ssz.go
@@ -1,6 +1,8 @@
 package solid
 
 import (
+	"encoding/json"
+
 	libcommon "github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon-lib/types/clonable"
 	"github.com/ledgerwatch/erigon-lib/types/ssz"
@@ -43,6 +45,14 @@ func NewStaticListSSZ[T encodableHashableSSZ](limit int, bytesPerElement int) *L
 	}
 }
 
+func (l ListSSZ[T]) MarshalJSON() ([]byte, error) {
+	return json.Marshal(l.list)
+}
+
+func (l *ListSSZ[T]) UnmarshalJSON(data []byte) error {
+	return json.Unmarshal(data, &l.list)
+}
+
 func NewDynamicListSSZFromList[T encodableHashableSSZ](list []T, limit int) *ListSSZ[T] {
 	return &ListSSZ[T]{
 		list:  list,
diff --git a/cl/cltypes/solid/transactions.go b/cl/cltypes/solid/transactions.go
index 73ba6c81a..40651ac85 100644
--- a/cl/cltypes/solid/transactions.go
+++ b/cl/cltypes/solid/transactions.go
@@ -1,7 +1,10 @@
 package solid
 
 import (
+	"encoding/json"
+
 	libcommon "github.com/ledgerwatch/erigon-lib/common"
+	"github.com/ledgerwatch/erigon-lib/common/hexutility"
 	"github.com/ledgerwatch/erigon-lib/types/clonable"
 	"github.com/ledgerwatch/erigon-lib/types/ssz"
 	"github.com/ledgerwatch/erigon/cl/merkle_tree"
@@ -12,6 +15,27 @@ type TransactionsSSZ struct {
 	root       libcommon.Hash // root
 }
 
+func (t *TransactionsSSZ) UnmarshalJSON(buf []byte) error {
+	tmp := []hexutility.Bytes{}
+	t.root = libcommon.Hash{}
+	if err := json.Unmarshal(buf, &tmp); err != nil {
+		return err
+	}
+	t.underlying = nil
+	for _, tx := range tmp {
+		t.underlying = append(t.underlying, tx)
+	}
+	return nil
+}
+
+func (t TransactionsSSZ) MarshalJSON() ([]byte, error) {
+	tmp := []hexutility.Bytes{}
+	for _, tx := range t.underlying {
+		tmp = append(tmp, tx)
+	}
+	return json.Marshal(tmp)
+}
+
 func (*TransactionsSSZ) Clone() clonable.Clonable {
 	return &TransactionsSSZ{}
 }
diff --git a/cl/cltypes/solid/uint64_list.go b/cl/cltypes/solid/uint64_list.go
index b57b5ae0d..a18eeec03 100644
--- a/cl/cltypes/solid/uint64_list.go
+++ b/cl/cltypes/solid/uint64_list.go
@@ -1,6 +1,8 @@
 package solid
 
 import (
+	"encoding/json"
+
 	"github.com/ledgerwatch/erigon-lib/types/clonable"
 )
 
@@ -14,6 +16,14 @@ func NewUint64ListSSZ(limit int) Uint64ListSSZ {
 	}
 }
 
+func (h uint64ListSSZ) MarshalJSON() ([]byte, error) {
+	return json.Marshal(h.u)
+}
+
+func (h uint64ListSSZ) UnmarshalJSON(buf []byte) error {
+	return json.Unmarshal(buf, h.u)
+}
+
 func (h *uint64ListSSZ) Static() bool {
 	return false
 }
diff --git a/cl/cltypes/solid/uint64_vector.go b/cl/cltypes/solid/uint64_vector.go
index 446d6cdbf..8ddb7f067 100644
--- a/cl/cltypes/solid/uint64_vector.go
+++ b/cl/cltypes/solid/uint64_vector.go
@@ -1,6 +1,8 @@
 package solid
 
 import (
+	"encoding/json"
+
 	"github.com/ledgerwatch/erigon-lib/types/clonable"
 )
 
@@ -19,6 +21,14 @@ func NewUint64VectorSSZ(size int) Uint64VectorSSZ {
 	}
 }
 
+func (h uint64VectorSSZ) MarshalJSON() ([]byte, error) {
+	return json.Marshal(h.u)
+}
+
+func (h *uint64VectorSSZ) UnmarshalJSON(buf []byte) error {
+	return json.Unmarshal(buf, h.u)
+}
+
 func (arr *uint64VectorSSZ) Clear() {
 	arr.u.Clear()
 }
diff --git a/cl/cltypes/solid/uint64slice_byte.go b/cl/cltypes/solid/uint64slice_byte.go
index 5b5e85d5d..00abb1785 100644
--- a/cl/cltypes/solid/uint64slice_byte.go
+++ b/cl/cltypes/solid/uint64slice_byte.go
@@ -2,6 +2,7 @@ package solid
 
 import (
 	"encoding/binary"
+	"encoding/json"
 
 	"github.com/ledgerwatch/erigon-lib/common"
 	"github.com/ledgerwatch/erigon-lib/common/length"
@@ -56,9 +57,26 @@ func (arr *byteBasedUint64Slice) CopyTo(target *byteBasedUint64Slice) {
 	copy(target.u, arr.u)
 }
 
-// depth returns the depth of the Merkle tree representing the slice.
-func (arr *byteBasedUint64Slice) depth() int {
-	return int(GetDepth(uint64(arr.c) / 4))
+func (arr *byteBasedUint64Slice) MarshalJSON() ([]byte, error) {
+	list := make([]uint64, arr.l)
+	for i := 0; i < arr.l; i++ {
+		list[0] = arr.Get(i)
+	}
+	return json.Marshal(list)
+}
+
+func (arr *byteBasedUint64Slice) UnmarshalJSON(buf []byte) error {
+	var list []uint64
+
+	if err := json.Unmarshal(buf, &list); err != nil {
+		return err
+	}
+	arr.Clear()
+	arr.l = len(list)
+	for _, elem := range list {
+		arr.Append(elem)
+	}
+	return nil
 }
 
 // Range iterates over the slice and applies a provided function to each element.
diff --git a/cl/cltypes/validator.go b/cl/cltypes/validator.go
index bfd99c9fe..83b5e04db 100644
--- a/cl/cltypes/validator.go
+++ b/cl/cltypes/validator.go
@@ -16,11 +16,10 @@ const (
 )
 
 type DepositData struct {
-	PubKey                [48]byte
-	WithdrawalCredentials libcommon.Hash
-	Amount                uint64
-	Signature             libcommon.Bytes96
-	Root                  libcommon.Hash // Ignored if not for hashing
+	PubKey                libcommon.Bytes48 `json:"pubkey"`
+	WithdrawalCredentials libcommon.Hash    `json:"withdrawal_credentials"`
+	Amount                uint64            `json:"amount"`
+	Signature             libcommon.Bytes96 `json:"signature"`
 }
 
 func (d *DepositData) EncodeSSZ(dst []byte) ([]byte, error) {
@@ -49,8 +48,8 @@ func (*DepositData) Static() bool {
 
 type Deposit struct {
 	// Merkle proof is used for deposits
-	Proof solid.HashVectorSSZ // 33 X 32 size.
-	Data  *DepositData
+	Proof solid.HashVectorSSZ `json:"proof"` // 33 X 32 size.
+	Data  *DepositData        `json:"data"`
 }
 
 func (d *Deposit) EncodeSSZ(dst []byte) ([]byte, error) {
@@ -73,8 +72,8 @@ func (d *Deposit) HashSSZ() ([32]byte, error) {
 }
 
 type VoluntaryExit struct {
-	Epoch          uint64
-	ValidatorIndex uint64
+	Epoch          uint64 `json:"epoch"`
+	ValidatorIndex uint64 `json:"validator_index"`
 }
 
 func (e *VoluntaryExit) EncodeSSZ(buf []byte) ([]byte, error) {
@@ -102,8 +101,8 @@ func (*VoluntaryExit) EncodingSizeSSZ() int {
 }
 
 type SignedVoluntaryExit struct {
-	VolunaryExit *VoluntaryExit
-	Signature    libcommon.Bytes96
+	VolunaryExit *VoluntaryExit    `json:"message"`
+	Signature    libcommon.Bytes96 `json:"signature"`
 }
 
 func (e *SignedVoluntaryExit) EncodeSSZ(dst []byte) ([]byte, error) {
diff --git a/cl/cltypes/validator_test.go b/cl/cltypes/validator_test.go
index c798a19c8..6ee34a39f 100644
--- a/cl/cltypes/validator_test.go
+++ b/cl/cltypes/validator_test.go
@@ -47,7 +47,6 @@ func TestDepositData(t *testing.T) {
 		WithdrawalCredentials: [32]byte{4, 5, 6},
 		Amount:                100,
 		Signature:             [96]byte{7, 8, 9},
-		Root:                  [32]byte{10, 11, 12},
 	}
 
 	// Encode DepositData to SSZ
diff --git a/cl/phase1/stages/stage_history_download.go b/cl/phase1/stages/stage_history_download.go
index 43e68056f..a95d80d75 100644
--- a/cl/phase1/stages/stage_history_download.go
+++ b/cl/phase1/stages/stage_history_download.go
@@ -3,6 +3,7 @@ package stages
 import (
 	"context"
 	"fmt"
+	"sync/atomic"
 	"time"
 
 	libcommon "github.com/ledgerwatch/erigon-lib/common"
@@ -96,8 +97,13 @@ func SpawnStageHistoryDownload(cfg StageHistoryReconstructionCfg, ctx context.Co
 		foundLatestEth1ValidHash = true // skip this if we are not using an engine supporting direct insertion
 	}
 
+	var currEth1Progress atomic.Int64
+
 	// Set up onNewBlock callback
 	cfg.downloader.SetOnNewBlock(func(blk *cltypes.SignedBeaconBlock) (finished bool, err error) {
+		if blk.Version() >= clparams.BellatrixVersion {
+			currEth1Progress.Store(int64(blk.Block.Body.ExecutionPayload.BlockNumber))
+		}
 		if !foundLatestEth1ValidHash {
 			payload := blk.Block.Body.ExecutionPayload
 			encodedPayload, err := payload.EncodeSSZ(nil)
@@ -136,7 +142,8 @@ func SpawnStageHistoryDownload(cfg StageHistoryReconstructionCfg, ctx context.Co
 					return
 				}
 				logArgs = append(logArgs,
-					"progress", currProgress,
+					"slot", currProgress,
+					"blockNumber", currEth1Progress.Load(),
 					"blk/sec", fmt.Sprintf("%.1f", speed),
 					"peers", peerCount)
 				logger.Info("Downloading History", logArgs...)