diff --git a/pkg/cannon/cannon.go b/pkg/cannon/cannon.go
index 4e494073..8de4a077 100644
--- a/pkg/cannon/cannon.go
+++ b/pkg/cannon/cannon.go
@@ -14,6 +14,7 @@ import (
 	//nolint:gosec // only exposed if pprofAddr config is set
 	_ "net/http/pprof"
 
+	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	"github.com/beevik/ntp"
 	"github.com/ethpandaops/ethwallclock"
@@ -690,7 +691,7 @@ func (c *Cannon) startDeriverWhenReady(ctx context.Context, d deriver.EventDeriv
 	for {
 		// Handle derivers that require phase0, since its not actually a fork it'll never appear
 		// in the spec.
-		if d.ActivationFork() != ethereum.ForkNamePhase0 {
+		if d.ActivationFork() != spec.DataVersionPhase0 {
 			spec, err := c.beacon.Node().Spec()
 			if err != nil {
 				c.log.WithError(err).Error("Failed to get spec")
@@ -700,7 +701,7 @@ func (c *Cannon) startDeriverWhenReady(ctx context.Context, d deriver.EventDeriv
 				continue
 			}
 
-			fork, err := spec.ForkEpochs.GetByName(d.ActivationFork())
+			fork, err := spec.ForkEpochs.GetByName(d.ActivationFork().String())
 			if err != nil {
 				c.log.WithError(err).Errorf("unknown activation fork: %s", d.ActivationFork())
 
diff --git a/pkg/cannon/deriver/beacon/eth/v1/beacon_blob.go b/pkg/cannon/deriver/beacon/eth/v1/beacon_blob.go
index ca07627c..52025871 100644
--- a/pkg/cannon/deriver/beacon/eth/v1/beacon_blob.go
+++ b/pkg/cannon/deriver/beacon/eth/v1/beacon_blob.go
@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"github.com/attestantio/go-eth2-client/api"
+	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/deneb"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	backoff "github.com/cenkalti/backoff/v4"
@@ -61,8 +62,8 @@ func (b *BeaconBlobDeriver) CannonType() xatu.CannonType {
 	return BeaconBlobDeriverName
 }
 
-func (b *BeaconBlobDeriver) ActivationFork() string {
-	return ethereum.ForkNameDeneb
+func (b *BeaconBlobDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionDeneb
 }
 
 func (b *BeaconBlobDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v1/beacon_committee.go b/pkg/cannon/deriver/beacon/eth/v1/beacon_committee.go
index 7f0b0e21..943cb0ff 100644
--- a/pkg/cannon/deriver/beacon/eth/v1/beacon_committee.go
+++ b/pkg/cannon/deriver/beacon/eth/v1/beacon_committee.go
@@ -6,6 +6,7 @@ import (
 	"time"
 
 	apiv1 "github.com/attestantio/go-eth2-client/api/v1"
+	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	backoff "github.com/cenkalti/backoff/v4"
 	"github.com/ethpandaops/xatu/pkg/cannon/ethereum"
@@ -59,8 +60,8 @@ func (b *BeaconCommitteeDeriver) CannonType() xatu.CannonType {
 	return BeaconCommitteeDeriverName
 }
 
-func (b *BeaconCommitteeDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *BeaconCommitteeDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *BeaconCommitteeDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v1/beacon_validators.go b/pkg/cannon/deriver/beacon/eth/v1/beacon_validators.go
index 1d5bc5e4..169f5672 100644
--- a/pkg/cannon/deriver/beacon/eth/v1/beacon_validators.go
+++ b/pkg/cannon/deriver/beacon/eth/v1/beacon_validators.go
@@ -6,6 +6,7 @@ import (
 	"time"
 
 	apiv1 "github.com/attestantio/go-eth2-client/api/v1"
+	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	backoff "github.com/cenkalti/backoff/v4"
 	"github.com/ethpandaops/xatu/pkg/cannon/ethereum"
@@ -60,8 +61,8 @@ func (b *BeaconValidatorsDeriver) CannonType() xatu.CannonType {
 	return BeaconValidatorsDeriverName
 }
 
-func (b *BeaconValidatorsDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *BeaconValidatorsDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *BeaconValidatorsDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v1/proposer_duty.go b/pkg/cannon/deriver/beacon/eth/v1/proposer_duty.go
index f52cd268..5eec0847 100644
--- a/pkg/cannon/deriver/beacon/eth/v1/proposer_duty.go
+++ b/pkg/cannon/deriver/beacon/eth/v1/proposer_duty.go
@@ -7,6 +7,7 @@ import (
 	"time"
 
 	apiv1 "github.com/attestantio/go-eth2-client/api/v1"
+	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	backoff "github.com/cenkalti/backoff/v4"
 	"github.com/ethpandaops/xatu/pkg/cannon/ethereum"
@@ -60,8 +61,8 @@ func (b *ProposerDutyDeriver) CannonType() xatu.CannonType {
 	return ProposerDutyDeriverName
 }
 
-func (b *ProposerDutyDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *ProposerDutyDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *ProposerDutyDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go b/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go
index f047b02d..7aa7cc9d 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go
@@ -58,8 +58,8 @@ func (a *AttesterSlashingDeriver) CannonType() xatu.CannonType {
 	return AttesterSlashingDeriverName
 }
 
-func (a *AttesterSlashingDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (a *AttesterSlashingDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (a *AttesterSlashingDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go b/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go
index 9c04a47d..3dbbbdb5 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go
@@ -62,8 +62,8 @@ func (b *BeaconBlockDeriver) CannonType() xatu.CannonType {
 	return BeaconBlockDeriverName
 }
 
-func (b *BeaconBlockDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *BeaconBlockDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *BeaconBlockDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go b/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go
index 740362e1..ab07828e 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go
@@ -68,8 +68,8 @@ func (b *BLSToExecutionChangeDeriver) OnEventsDerived(ctx context.Context, fn fu
 	b.onEventsCallbacks = append(b.onEventsCallbacks, fn)
 }
 
-func (b *BLSToExecutionChangeDeriver) ActivationFork() string {
-	return ethereum.ForkNameCapella
+func (b *BLSToExecutionChangeDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionCapella
 }
 
 func (b *BLSToExecutionChangeDeriver) Start(ctx context.Context) error {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/deposit.go b/pkg/cannon/deriver/beacon/eth/v2/deposit.go
index 9eb3f558..1d3b389c 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/deposit.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/deposit.go
@@ -62,8 +62,8 @@ func (b *DepositDeriver) Name() string {
 	return DepositDeriverName.String()
 }
 
-func (b *DepositDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *DepositDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *DepositDeriver) OnEventsDerived(ctx context.Context, fn func(ctx context.Context, events []*xatu.DecoratedEvent) error) {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/elaborated_attestation.go b/pkg/cannon/deriver/beacon/eth/v2/elaborated_attestation.go
index dc3d74e4..ad9bf8c4 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/elaborated_attestation.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/elaborated_attestation.go
@@ -63,8 +63,8 @@ func (b *ElaboratedAttestationDeriver) Name() string {
 	return ElaboratedAttestationDeriverName.String()
 }
 
-func (b *ElaboratedAttestationDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *ElaboratedAttestationDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *ElaboratedAttestationDeriver) OnEventsDerived(ctx context.Context, fn func(ctx context.Context, events []*xatu.DecoratedEvent) error) {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go b/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go
index 69a6f7ad..02b23ff4 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go
@@ -63,8 +63,8 @@ func (b *ExecutionTransactionDeriver) CannonType() xatu.CannonType {
 	return ExecutionTransactionDeriverName
 }
 
-func (b *ExecutionTransactionDeriver) ActivationFork() string {
-	return ethereum.ForkNameBellatrix
+func (b *ExecutionTransactionDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionBellatrix
 }
 
 func (b *ExecutionTransactionDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go b/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go
index f265273f..17537f39 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go
@@ -62,8 +62,8 @@ func (b *ProposerSlashingDeriver) Name() string {
 	return ProposerSlashingDeriverName.String()
 }
 
-func (b *ProposerSlashingDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *ProposerSlashingDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *ProposerSlashingDeriver) OnEventsDerived(ctx context.Context, fn func(ctx context.Context, events []*xatu.DecoratedEvent) error) {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go b/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go
index 9cbcc9b8..f402d300 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go
@@ -58,8 +58,8 @@ func (b *VoluntaryExitDeriver) CannonType() xatu.CannonType {
 	return VoluntaryExitDeriverName
 }
 
-func (b *VoluntaryExitDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *VoluntaryExitDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *VoluntaryExitDeriver) Name() string {
diff --git a/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go b/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go
index ef54a18e..585f09be 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go
@@ -62,8 +62,8 @@ func (b *WithdrawalDeriver) Name() string {
 	return WithdrawalDeriverName.String()
 }
 
-func (b *WithdrawalDeriver) ActivationFork() string {
-	return ethereum.ForkNameCapella
+func (b *WithdrawalDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionCapella
 }
 
 func (b *WithdrawalDeriver) OnEventsDerived(ctx context.Context, fn func(ctx context.Context, events []*xatu.DecoratedEvent) error) {
diff --git a/pkg/cannon/deriver/blockprint/block_classification.go b/pkg/cannon/deriver/blockprint/block_classification.go
index 1033c875..d2086609 100644
--- a/pkg/cannon/deriver/blockprint/block_classification.go
+++ b/pkg/cannon/deriver/blockprint/block_classification.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	backoff "github.com/cenkalti/backoff/v4"
 	aBlockprint "github.com/ethpandaops/xatu/pkg/cannon/blockprint"
@@ -67,8 +68,8 @@ func (b *BlockClassificationDeriver) CannonType() xatu.CannonType {
 	return BlockClassificationName
 }
 
-func (b *BlockClassificationDeriver) ActivationFork() string {
-	return ethereum.ForkNamePhase0
+func (b *BlockClassificationDeriver) ActivationFork() spec.DataVersion {
+	return spec.DataVersionPhase0
 }
 
 func (b *BlockClassificationDeriver) Name() string {
diff --git a/pkg/cannon/deriver/event_deriver.go b/pkg/cannon/deriver/event_deriver.go
index 8aa42ed5..e89090b2 100644
--- a/pkg/cannon/deriver/event_deriver.go
+++ b/pkg/cannon/deriver/event_deriver.go
@@ -3,6 +3,7 @@ package deriver
 import (
 	"context"
 
+	"github.com/attestantio/go-eth2-client/spec"
 	v1 "github.com/ethpandaops/xatu/pkg/cannon/deriver/beacon/eth/v1"
 	v2 "github.com/ethpandaops/xatu/pkg/cannon/deriver/beacon/eth/v2"
 	"github.com/ethpandaops/xatu/pkg/cannon/deriver/blockprint"
@@ -17,7 +18,7 @@ type EventDeriver interface {
 	// Callbacks
 	OnEventsDerived(ctx context.Context, fn func(ctx context.Context, events []*xatu.DecoratedEvent) error)
 	// ActivationFork is the fork at which the deriver should start deriving events
-	ActivationFork() string
+	ActivationFork() spec.DataVersion
 }
 
 // Ensure that derivers implements the EventDeriver interface
diff --git a/pkg/cannon/ethereum/forks.go b/pkg/cannon/ethereum/forks.go
deleted file mode 100644
index 2fd6d1d5..00000000
--- a/pkg/cannon/ethereum/forks.go
+++ /dev/null
@@ -1,10 +0,0 @@
-package ethereum
-
-var (
-	ForkNamePhase0    = "PHASE0"
-	ForkNameAltair    = "ALTAIR"
-	ForkNameBellatrix = "BELLATRIX"
-	ForkNameCapella   = "CAPELLA"
-	ForkNameDeneb     = "DENEB"
-	ForkNameElectra   = "ELECTRA"
-)