diff --git a/.github/workflows/lint.yaml b/.github/workflows/lint.yaml
index fe81380..dc11bf2 100644
--- a/.github/workflows/lint.yaml
+++ b/.github/workflows/lint.yaml
@@ -9,15 +9,11 @@ on:
 jobs:
   lint:
     runs-on: ubuntu-20.04
-    container: golangci/golangci-lint:v1.43.0
     steps:
       - uses: actions/checkout@v2
-      - uses: actions/cache@v2
+      - uses: actions/setup-go@v2
         with:
-          path: |
-            ~/.cache/go-build
-            /go/pkg/mod
-          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-          restore-keys: |
-            ${{ runner.os }}-go-
-      - run: golangci-lint run
+          go-version: 1.18.0
+      - uses: golangci/golangci-lint-action@v2
+        with:
+          version: v1.45.0
diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index 0a75424..ccf7e73 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -11,7 +11,8 @@ jobs:
     strategy:
       matrix:
         containers:
-          - 1.17.2-bullseye
+          - 1.17.8-bullseye
+          - 1.18.0-bullseye
     runs-on: ubuntu-20.04
     container: golang:${{matrix.containers}}
     steps:
diff --git a/claim.go b/claim.go
index 11075d9..58897f8 100644
--- a/claim.go
+++ b/claim.go
@@ -9,7 +9,6 @@ import (
 	"time"
 
 	"github.com/iden3/go-iden3-crypto/utils"
-	"github.com/iden3/go-merkletree-sql"
 )
 
 /*
@@ -57,7 +56,7 @@ var ErrIncorrectIDPosition = errors.New("incorrect ID position")
 // ErrNoID returns when ID not found in the Claim.
 var ErrNoID = errors.New("ID is not set")
 
-// ErrSlotOverflow means some DataSlot overflows Q Field. And wraps the name
+// ErrSlotOverflow means some ElemBytes overflows Q Field. And wraps the name
 // of overflowed slot.
 type ErrSlotOverflow struct {
 	Field SlotName
@@ -91,50 +90,9 @@ func (sc SchemaHash) MarshalText() ([]byte, error) {
 	return dst, nil
 }
 
-// DataSlot length is 32 bytes. But not all 32-byte values are valid.
-// The value should be not greater than Q constant
-// 21888242871839275222246405745257275088548364400416034343698204186575808495617
-type DataSlot [32]byte
-
-// ToInt returns *big.Int representation of DataSlot.
-func (ds DataSlot) ToInt() *big.Int {
-	return new(big.Int).SetBytes(utils.SwapEndianness(ds[:]))
-}
-
-// SetInt sets data slot to serialized value of *big.Int. And checks that the
-// value is valid (fills in Field Q).
-// Returns ErrDataOverflow if the value is too large
-func (ds *DataSlot) SetInt(value *big.Int) error {
-	if !utils.CheckBigIntInField(value) {
-		return ErrDataOverflow
-	}
-
-	val := utils.SwapEndianness(value.Bytes())
-	copy((*ds)[:], val)
-	memset((*ds)[len(val):], 0)
-	return nil
-}
-
-// NewDataSlotFromInt creates new DataSlot from *big.Int.
-// Returns error ErrDataOverflow if value is too large to fill the Field Q.
-func NewDataSlotFromInt(i *big.Int) (DataSlot, error) {
-	var s DataSlot
-	bs := i.Bytes()
-	// may be this check is redundant because of CheckBigIntInField, but just
-	// in case.
-	if len(bs) > len(s) {
-		return s, ErrDataOverflow
-	}
-	if !utils.CheckBigIntInField(i) {
-		return s, ErrDataOverflow
-	}
-	copy(s[:], utils.SwapEndianness(bs))
-	return s, nil
-}
-
 type Claim struct {
-	index [4]DataSlot
-	value [4]DataSlot
+	index [4]ElemBytes
+	value [4]ElemBytes
 }
 
 // Subject for the time being describes the location of ID (in index or value
@@ -236,7 +194,7 @@ func WithExpirationDate(dt time.Time) Option {
 
 // WithIndexData sets data to index slots A & B.
 // Returns ErrSlotOverflow if slotA or slotB value are too big.
-func WithIndexData(slotA, slotB DataSlot) Option {
+func WithIndexData(slotA, slotB ElemBytes) Option {
 	return func(c *Claim) error {
 		return c.SetIndexData(slotA, slotB)
 	}
@@ -260,7 +218,7 @@ func WithIndexDataInts(slotA, slotB *big.Int) Option {
 
 // WithValueData sets data to value slots A & B.
 // Returns ErrSlotOverflow if slotA or slotB value are too big.
-func WithValueData(slotA, slotB DataSlot) Option {
+func WithValueData(slotA, slotB ElemBytes) Option {
 	return func(c *Claim) error {
 		return c.SetValueData(slotA, slotB)
 	}
@@ -451,7 +409,7 @@ func (c *Claim) GetExpirationDate() (time.Time, bool) {
 
 // SetIndexData sets data to index slots A & B.
 // Returns ErrSlotOverflow if slotA or slotB value are too big.
-func (c *Claim) SetIndexData(slotA, slotB DataSlot) error {
+func (c *Claim) SetIndexData(slotA, slotB ElemBytes) error {
 	slotsAsInts := []*big.Int{slotA.ToInt(), slotB.ToInt()}
 	if !utils.CheckBigIntArrayInField(slotsAsInts) {
 		return ErrDataOverflow
@@ -484,7 +442,7 @@ func (c *Claim) SetIndexDataInts(slotA, slotB *big.Int) error {
 
 // SetValueData sets data to value slots A & B.
 // Returns ErrSlotOverflow if slotA or slotB value are too big.
-func (c *Claim) SetValueData(slotA, slotB DataSlot) error {
+func (c *Claim) SetValueData(slotA, slotB ElemBytes) error {
 	slotsAsInts := []*big.Int{slotA.ToInt(), slotB.ToInt()}
 	if !utils.CheckBigIntArrayInField(slotsAsInts) {
 		return ErrDataOverflow
@@ -515,7 +473,7 @@ func (c *Claim) SetValueDataInts(slotA, slotB *big.Int) error {
 	return setSlotInt(&c.value[3], slotB, SlotNameValueB)
 }
 
-func setSlotBytes(slot *DataSlot, value []byte, slotName SlotName) error {
+func setSlotBytes(slot *ElemBytes, value []byte, slotName SlotName) error {
 	if len(value) > len(*slot) {
 		return ErrSlotOverflow{slotName}
 	}
@@ -527,8 +485,7 @@ func setSlotBytes(slot *DataSlot, value []byte, slotName SlotName) error {
 	return nil
 }
 
-func setSlotInt(slot *DataSlot, value *big.Int, slotName SlotName) error {
-
+func setSlotInt(slot *ElemBytes, value *big.Int, slotName SlotName) error {
 	if value == nil {
 		value = big.NewInt(0)
 	}
@@ -540,17 +497,9 @@ func setSlotInt(slot *DataSlot, value *big.Int, slotName SlotName) error {
 	return err
 }
 
-// TreeEntry creates new merkletree.Entry from the claim. Following changes to
-// claim does not change returned merkletree.Entry.
-func (c *Claim) TreeEntry() merkletree.Entry {
-	var e merkletree.Entry
-	for i := range c.index {
-		copy(e.Data[i][:], c.index[i][:])
-	}
-	for i := range c.value {
-		copy(e.Data[i+len(c.index)][:], c.value[i][:])
-	}
-	return e
+// RawSlots returns raw bytes of claim's index and value
+func (c *Claim) RawSlots() (index [4]ElemBytes, value [4]ElemBytes) {
+	return c.index, c.value
 }
 
 // Clone returns full deep copy of claim
diff --git a/claim_test.go b/claim_test.go
index 1fda1eb..7564c6c 100644
--- a/claim_test.go
+++ b/claim_test.go
@@ -10,8 +10,8 @@ import (
 	"testing"
 	"time"
 
+	"github.com/iden3/go-iden3-crypto/poseidon"
 	"github.com/iden3/go-iden3-crypto/utils"
-
 	"github.com/stretchr/testify/require"
 )
 
@@ -37,34 +37,33 @@ func TestNewClaim(t *testing.T) {
 	require.False(t, ok)
 }
 
-func (ds DataSlot) String() string {
+func (el ElemBytes) String() string {
 	var b bytes.Buffer
-	for j := len(ds) - 1; j >= 0; j-- {
-		b.WriteString(fmt.Sprintf("% 08b", ds[j]))
+	for j := len(el) - 1; j >= 0; j-- {
+		b.WriteString(fmt.Sprintf("% 08b", el[j]))
 	}
 	return b.String()
 }
 
-func TestMerketreeEntryHash(t *testing.T) {
+func TestRawSlots(t *testing.T) {
 	var schemaHash SchemaHash
 	claim, err := NewClaim(schemaHash, WithFlagUpdatable(true))
 	require.NoError(t, err)
-	e := claim.TreeEntry()
-
-	hi, hv, err := e.HiHv()
+	index, value := claim.RawSlots()
+	indexHash, err := poseidon.Hash([]*big.Int{
+		index[0].ToInt(), index[1].ToInt(), index[2].ToInt(), index[3].ToInt()})
 	require.NoError(t, err)
-
-	hit, err := hi.MarshalText()
+	valueHash, err := poseidon.Hash([]*big.Int{
+		value[0].ToInt(), value[1].ToInt(), value[2].ToInt(), value[3].ToInt()})
 	require.NoError(t, err)
+
 	require.Equal(t,
 		"19905260441950906049955646784794273651462264973332746773406911374272567544299",
-		string(hit))
+		indexHash.Text(10))
 
-	hvt, err := hv.MarshalText()
-	require.NoError(t, err)
 	require.Equal(t,
 		"2351654555892372227640888372176282444150254868378439619268573230312091195718",
-		string(hvt))
+		valueHash.Text(10))
 }
 
 func TestClaim_GetSchemaHash(t *testing.T) {
@@ -74,7 +73,8 @@ func TestClaim_GetSchemaHash(t *testing.T) {
 	require.Equal(t, schemaHashLn, n)
 	claim, err := NewClaim(sc)
 	require.NoError(t, err)
-	require.True(t, bytes.Equal(sc[:], utils.SwapEndianness(claim.index[0][:schemaHashLn])))
+	require.True(t,
+		bytes.Equal(sc[:], utils.SwapEndianness(claim.index[0][:schemaHashLn])))
 
 	shFromClaim := claim.GetSchemaHash()
 	shFromClaimHexBytes, err := shFromClaim.MarshalText()
@@ -159,18 +159,22 @@ func toInt(t testing.TB, s string) *big.Int {
 }
 
 func TestIntSize(t *testing.T) {
-	iX := toInt(t, "16243864111864693853212588481963275789994876191154110553066821559749894481761")
-	iY := toInt(t, "7078462697308959301666117070269719819629678436794910510259518359026273676830")
-	vX := toInt(t, "12448278679517811784508557734102986855579744384337338465055621486538311281772")
-	vY := toInt(t, "9260608685281348956030279125705000716237952776955782848598673606545494194823")
+	iX := toInt(t,
+		"16243864111864693853212588481963275789994876191154110553066821559749894481761")
+	iY := toInt(t,
+		"7078462697308959301666117070269719819629678436794910510259518359026273676830")
+	vX := toInt(t,
+		"12448278679517811784508557734102986855579744384337338465055621486538311281772")
+	vY := toInt(t,
+		"9260608685281348956030279125705000716237952776955782848598673606545494194823")
 
-	ixSlot, err := NewDataSlotFromInt(iX)
+	ixSlot, err := NewElemBytesFromInt(iX)
 	require.NoError(t, err)
-	iySlot, err := NewDataSlotFromInt(iY)
+	iySlot, err := NewElemBytesFromInt(iY)
 	require.NoError(t, err)
-	vxSlot, err := NewDataSlotFromInt(vX)
+	vxSlot, err := NewElemBytesFromInt(vX)
 	require.NoError(t, err)
-	vySlot, err := NewDataSlotFromInt(vY)
+	vySlot, err := NewElemBytesFromInt(vY)
 	require.NoError(t, err)
 	_, err = NewClaim(SchemaHash{},
 		WithIndexData(ixSlot, iySlot),
@@ -179,10 +183,10 @@ func TestIntSize(t *testing.T) {
 }
 
 func TestNewDataSlotFromInt(t *testing.T) {
-	ds, err := NewDataSlotFromInt(toInt(t,
+	ds, err := NewElemBytesFromInt(toInt(t,
 		"16243864111864693853212588481963275789994876191154110553066821559749894481761"))
 	require.NoError(t, err)
-	expected := DataSlot{
+	expected := ElemBytes{
 		0x61, 0x27, 0xa0, 0xeb, 0x58, 0x7a, 0x6c, 0x2b,
 		0x4a, 0xa8, 0xc1, 0x2e, 0xf5, 0x01, 0xb2, 0xdb,
 		0xd0, 0x9c, 0xb1, 0xa5, 0x9c, 0x83, 0x42, 0x57,
@@ -190,14 +194,14 @@ func TestNewDataSlotFromInt(t *testing.T) {
 	}
 	require.Equal(t, expected, ds)
 
-	_, err = NewDataSlotFromInt(toInt(t,
+	_, err = NewElemBytesFromInt(toInt(t,
 		"9916243864111864693853212588481963275789994876191154110553066821559749894481761"))
 	require.EqualError(t, err, ErrDataOverflow.Error())
 }
 
 func TestClaim_WithIndexDataInts(t *testing.T) {
 
-	expSlot := DataSlot{}
+	expSlot := ElemBytes{}
 	err := expSlot.SetInt(big.NewInt(0))
 	require.NoError(t, err)
 
@@ -216,7 +220,7 @@ func TestClaim_WithIndexDataInts(t *testing.T) {
 
 func TestClaim_WithValueDataInts(t *testing.T) {
 
-	expSlot := DataSlot{}
+	expSlot := ElemBytes{}
 	err := expSlot.SetInt(big.NewInt(0))
 	require.NoError(t, err)
 
@@ -236,8 +240,9 @@ func TestClaim_WithValueDataInts(t *testing.T) {
 
 func TestClaim_WithIndexDataBytes(t *testing.T) {
 
-	iX := toInt(t, "124482786795178117845085577341029868555797443843373384650556214865383112817")
-	expSlot := DataSlot{}
+	iX := toInt(t,
+		"124482786795178117845085577341029868555797443843373384650556214865383112817")
+	expSlot := ElemBytes{}
 	err := expSlot.SetInt(big.NewInt(0))
 	require.NoError(t, err)
 
diff --git a/elem_bytes.go b/elem_bytes.go
new file mode 100644
index 0000000..3079ac0
--- /dev/null
+++ b/elem_bytes.go
@@ -0,0 +1,63 @@
+package core
+
+import (
+	"encoding/hex"
+	"math/big"
+
+	"github.com/iden3/go-iden3-crypto/utils"
+)
+
+// ElemBytes length is 32 bytes. But not all 32-byte values are valid.
+// The value should be not greater than Q constant
+// 21888242871839275222246405745257275088548364400416034343698204186575808495617
+type ElemBytes [32]byte
+
+// ToInt returns *big.Int representation of ElemBytes.
+func (el ElemBytes) ToInt() *big.Int {
+	return new(big.Int).SetBytes(utils.SwapEndianness(el[:]))
+}
+
+// SetInt sets element's data to serialized value of *big.Int in little-endian.
+// And checks that the value is valid (fits in Field Q).
+// Returns ErrDataOverflow if the value is too large
+func (el *ElemBytes) SetInt(value *big.Int) error {
+	if !utils.CheckBigIntInField(value) {
+		return ErrDataOverflow
+	}
+
+	val := utils.SwapEndianness(value.Bytes())
+	copy((*el)[:], val)
+	memset((*el)[len(val):], 0)
+	return nil
+}
+
+// Hex returns HEX representation of ElemBytes
+func (el ElemBytes) Hex() string {
+	return hex.EncodeToString(el[:])
+}
+
+// NewElemBytesFromInt creates new ElemBytes from *big.Int.
+// Returns error ErrDataOverflow if value is too large to fill the Field Q.
+func NewElemBytesFromInt(i *big.Int) (ElemBytes, error) {
+	var s ElemBytes
+	bs := i.Bytes()
+	// may be this check is redundant because of CheckBigIntInField, but just
+	// in case.
+	if len(bs) > len(s) {
+		return s, ErrDataOverflow
+	}
+	if !utils.CheckBigIntInField(i) {
+		return s, ErrDataOverflow
+	}
+	copy(s[:], utils.SwapEndianness(bs))
+	return s, nil
+}
+
+// ElemBytesToInts converts slice of ElemBytes to slice of *big.Int
+func ElemBytesToInts(elements []ElemBytes) []*big.Int {
+	result := make([]*big.Int, len(elements))
+	for i := range elements {
+		result[i] = elements[i].ToInt()
+	}
+	return result
+}
diff --git a/example_test.go b/example_test.go
index c992e15..39f1228 100644
--- a/example_test.go
+++ b/example_test.go
@@ -4,6 +4,8 @@ import (
 	"encoding/hex"
 	"fmt"
 	"time"
+
+	"github.com/iden3/go-iden3-crypto/poseidon"
 )
 
 func ExampleNewClaim() {
@@ -21,13 +23,27 @@ func ExampleNewClaim() {
 
 	fmt.Println(claim.GetVersion())
 
-	entry := claim.TreeEntry()
-	indexHash, valueHash, err := entry.HiHv()
+	indexEntry, valueEntry := claim.RawSlots()
+	indexHash, err := poseidon.Hash(ElemBytesToInts(indexEntry[:]))
+	if err != nil {
+		panic(err)
+	}
+	valueHash, err := poseidon.Hash(ElemBytesToInts(valueEntry[:]))
+	if err != nil {
+		panic(err)
+	}
+
+	indexSlot, err := NewElemBytesFromInt(indexHash)
+	if err != nil {
+		panic(err)
+	}
+	valueSlot, err := NewElemBytesFromInt(valueHash)
 	if err != nil {
 		panic(err)
 	}
-	fmt.Println(hex.EncodeToString(indexHash[:]))
-	fmt.Println(hex.EncodeToString(valueHash[:]))
+
+	fmt.Println(hex.EncodeToString(indexSlot[:]))
+	fmt.Println(hex.EncodeToString(valueSlot[:]))
 	// Output:
 	// true
 	// 2021-01-10T20:30:00Z
diff --git a/go.mod b/go.mod
index 4c144fc..aae8cc9 100644
--- a/go.mod
+++ b/go.mod
@@ -3,8 +3,7 @@ module github.com/iden3/go-iden3-core
 go 1.17
 
 require (
-	github.com/iden3/go-iden3-crypto v0.0.11
-	github.com/iden3/go-merkletree-sql v1.0.0-pre8
+	github.com/iden3/go-iden3-crypto v0.0.13
 	github.com/mr-tron/base58 v1.2.0
 	github.com/stretchr/testify v1.7.0
 )
@@ -12,5 +11,6 @@ require (
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e // indirect
 	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
 )
diff --git a/go.sum b/go.sum
index 0919e0a..7387980 100644
--- a/go.sum
+++ b/go.sum
@@ -2,10 +2,10 @@ github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dchest/blake512 v1.0.0/go.mod h1:FV1x7xPPLWukZlpDpWQ88rF/SFwZ5qbskrzhLMB92JI=
-github.com/iden3/go-iden3-crypto v0.0.11 h1:5cFQ/BIqH9gjwe9Z68Hmc5jOTGqmMYnewIaTGCeO+6A=
-github.com/iden3/go-iden3-crypto v0.0.11/go.mod h1:yUBWcXgAUDZxa1PvRl0zIT4Q4/rQO5PacE52Z06i8kw=
-github.com/iden3/go-merkletree-sql v1.0.0-pre8 h1:ywL4VaBnpMGRLQUbSGgXXOjSHIo33KEEiBvrK2AnRa8=
-github.com/iden3/go-merkletree-sql v1.0.0-pre8/go.mod h1:oYLAGBrr1/yNBZWhpE3JTxtbgDf6d56oRCbdjT1UX9A=
+github.com/iden3/go-iden3-crypto v0.0.13 h1:ixWRiaqDULNyIDdOWz2QQJG5t4PpNHkQk2P6GV94cok=
+github.com/iden3/go-iden3-crypto v0.0.13/go.mod h1:swXIv0HFbJKobbQBtsB50G7IHr6PbTowutSew/iBEoo=
+github.com/leanovate/gopter v0.2.9 h1:fQjYxZaynp97ozCzfOyOuAGOU4aU/z37zf/tOujFk7c=
+github.com/leanovate/gopter v0.2.9/go.mod h1:U2L/78B+KVFIx2VmW6onHJQzXtFb+p5y3y2Sh+Jxxv8=
 github.com/mr-tron/base58 v1.2.0 h1:T/HDJBh4ZCPbU39/+c3rRvE0uKBQlU27+QI8LJ4t64o=
 github.com/mr-tron/base58 v1.2.0/go.mod h1:BinMc/sQntlIE1frQmRFPUoPA1Zkr8VRgBdjWI2mNwc=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -18,6 +18,8 @@ golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qx
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e h1:fLOSk5Q00efkSvAm+4xcoXD+RRmLmmulPn5I3Y9F2EM=
+golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
diff --git a/id.go b/id.go
index 91e2cfb..97a3da2 100644
--- a/id.go
+++ b/id.go
@@ -6,7 +6,6 @@ import (
 	"math/big"
 
 	"github.com/iden3/go-iden3-crypto/poseidon"
-	"github.com/iden3/go-merkletree-sql"
 	"github.com/mr-tron/base58"
 )
 
@@ -51,9 +50,9 @@ func (id *ID) Bytes() []byte {
 }
 
 func (id *ID) BigInt() *big.Int {
-	var idElem merkletree.ElemBytes
-	copy(idElem[:], id[:])
-	return idElem.BigInt()
+	var s ElemBytes
+	copy(s[:], id[:])
+	return s.ToInt()
 }
 
 func (id *ID) Equal(id2 *ID) bool {
@@ -153,37 +152,37 @@ func CheckChecksum(id ID) bool {
 }
 
 // IdGenesisFromIdenState calculates the genesis Id from an Identity State.
-func IdGenesisFromIdenState(hash *merkletree.Hash) *ID { //nolint:revive
+func IdGenesisFromIdenState(state ElemBytes) *ID { //nolint:revive
 	var idGenesisBytes [27]byte
-	rootBytes := hash.Bytes()
-	rootBytes = merkletree.SwapEndianness(rootBytes)
 	// we take last 27 bytes, because of swapped endianness
-	copy(idGenesisBytes[:], rootBytes[len(rootBytes)-27:])
+	copy(idGenesisBytes[:], state[len(state)-27:])
 	id := NewID(TypeDefault, idGenesisBytes)
 	return &id
 }
 
-// IdenState calculates the Identity State from the Claims Tree Root, Revocation Tree Root and Roots Tree Root.
-func IdenState(clr *merkletree.Hash,
-	rer *merkletree.Hash,
-	ror *merkletree.Hash) *merkletree.Hash {
-	bi := merkletree.ElemBytesToBigInts([]merkletree.ElemBytes{
-		merkletree.ElemBytes(*clr),
-		merkletree.ElemBytes(*rer),
-		merkletree.ElemBytes(*ror)})
-	idenState, err := poseidon.Hash(bi)
+// IdenState calculates the Identity State from the Claims Tree Root,
+// Revocation Tree Root and Roots Tree Root.
+func IdenState(clr ElemBytes, rer ElemBytes,
+	ror ElemBytes) (ElemBytes, error) {
+
+	idenState, err := poseidon.Hash([]*big.Int{
+		clr.ToInt(), rer.ToInt(), ror.ToInt()})
 	if err != nil {
-		panic(err)
+		return ElemBytes{}, err
 	}
-	return merkletree.NewHashFromBigInt(idenState)
+	return NewElemBytesFromInt(idenState)
 }
 
 // CalculateGenesisID calculate genesis id based on provided claims tree root
-func CalculateGenesisID(clr *merkletree.Hash) (*ID, error) {
-	idenState, err := merkletree.HashElems(clr.BigInt(),
-		merkletree.HashZero.BigInt(), merkletree.HashZero.BigInt())
+func CalculateGenesisID(clr ElemBytes) (*ID, error) {
+	idenState, err := poseidon.Hash([]*big.Int{
+		clr.ToInt(), big.NewInt(0), big.NewInt(0)})
+	if err != nil {
+		return nil, err
+	}
+	idenStateData, err := NewElemBytesFromInt(idenState)
 	if err != nil {
 		return nil, err
 	}
-	return IdGenesisFromIdenState(idenState), nil
+	return IdGenesisFromIdenState(idenStateData), nil
 }