diff --git a/consensus/ethash/ethash.go b/consensus/ethash/ethash.go
index 978e6ee..98d3614 100644
--- a/consensus/ethash/ethash.go
+++ b/consensus/ethash/ethash.go
@@ -359,7 +359,7 @@ func (c *cache) generate(dir string, limit int, lock bool, test bool) {
 				// Else the file is unrecognized (unknown name format), leave it alone.
 				continue
 			}
-			if e <= c.epoch-uint64(limit) || e > c.epoch+1 {
+			if (c.epoch >= uint64(limit) && e <= c.epoch-uint64(limit)) || e > c.epoch+1 { // SCDO patch: uint64 underflow fix
 				if err := os.Remove(file); err == nil {
 					logger.Debug("Deleted ethash cache file", "target.epoch", e, "file", file)
 				} else {
@@ -472,7 +472,8 @@ func (d *dataset) generate(dir string, limit int, lock bool, test bool) {
 				// Else the file is unrecognized (unknown name format), leave it alone.
 				continue
 			}
-			if e <= d.epoch-uint64(limit) || e > d.epoch+1 {
+			// SCDO patch 2026-09-28: avoid uint64 underflow for epoch < limit, which deleted the live epoch-0/1 DAG file
+			if (d.epoch >= uint64(limit) && e <= d.epoch-uint64(limit)) || e > d.epoch+1 {
 				if err := os.Remove(file); err == nil {
 					logger.Debug("Deleted ethash full file", "target.epoch", e, "file", file)
 				} else {
diff --git a/consensus/lyra2/lyra2.go b/consensus/lyra2/lyra2.go
index a17794f..9058fbb 100644
--- a/consensus/lyra2/lyra2.go
+++ b/consensus/lyra2/lyra2.go
@@ -1,20 +1,10 @@
 package lyra2
 
-/*
-#cgo CFLAGS: -std=gnu99
-#include "Lyra2.h"
-#include <stdlib.h>
-*/
-import "C"
 import (
-	"encoding/binary"
-	"math/big"
 	"math/rand"
 	"sync"
 	"time"
-	"unsafe"
 
-	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/metrics"
@@ -80,34 +70,6 @@ func NewTester(notify []string, noverify bool) *Lyra2 {
 	return lyra2
 }
 
-func (lyra2 *Lyra2) calcHash(headerBytes []byte, nonce uint64, tcost int) *big.Int {
-	var lyra2_ctx unsafe.Pointer = C.LYRA2_create()
-	result := lyra2.compute(lyra2_ctx, headerBytes, nonce, tcost)
-	C.LYRA2_destroy(lyra2_ctx)
-
-	return result.Big()
-}
-
-func bytesToHash(in unsafe.Pointer) common.Hash {
-	return *(*common.Hash)(in)
-}
-
-func (lyra2 *Lyra2) compute(ctx unsafe.Pointer, blockBytes []byte, nonce uint64, tcost int) common.Hash {
-	binary.BigEndian.PutUint64(blockBytes[len(blockBytes)-8:], nonce)
-
-	var in unsafe.Pointer = C.CBytes(blockBytes)
-	var out unsafe.Pointer = C.malloc(common.HashLength)
-
-	C.LYRA2(ctx, out, common.HashLength, in, C.int32_t(len(blockBytes)), C.int32_t(tcost))
-
-	hash := bytesToHash(out)
-
-	C.free(in)
-	C.free(out)
-
-	return hash
-}
-
 func (lyra2 *Lyra2) Close() error {
 	return nil
 }
diff --git a/core/vm/evm.go b/core/vm/evm.go
index 6625fbf..3c600df 100644
--- a/core/vm/evm.go
+++ b/core/vm/evm.go
@@ -21,7 +21,6 @@ import (
 	"math/big"
 	"sync/atomic"
 
-	"github.com/ethereum/evmc/v7/bindings/go/evmc"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
@@ -171,11 +170,11 @@ func NewEVM(blockCtx BlockContext, txCtx TxContext, statedb StateDB, chainConfig
 	// In some implementations, EWASM may be configured with a block number.
 	// In this implementation, the interpreter is configured globally instead.
 	if config.EWASMInterpreter != "" {
-		evm.interpreters = append(evm.interpreters, &EVMC{ewasmModule, evm, evmc.CapabilityEWASM, false})
+		evm.interpreters = append(evm.interpreters, newEVMCInterpreter(evm, true))
 	}
 
 	if config.EVMInterpreter != "" {
-		evm.interpreters = append(evm.interpreters, &EVMC{evmModule, evm, evmc.CapabilityEVM1, false})
+		evm.interpreters = append(evm.interpreters, newEVMCInterpreter(evm, false))
 	} else {
 		evm.interpreters = append(evm.interpreters, NewEVMInterpreter(evm))
 	}
diff --git a/core/vm/evmc.go b/core/vm/evmc.go
index ec338c4..5c5d7e5 100644
--- a/core/vm/evmc.go
+++ b/core/vm/evmc.go
@@ -1,3 +1,5 @@
+//go:build cgo
+
 // Copyright 2019 The go-ethereum Authors
 // This file is part of the go-ethereum library.
 //
@@ -425,3 +427,11 @@ func (evm *EVMC) CanRun(code []byte) bool {
 	}
 	return evm.cap == required
 }
+
+// newEVMCInterpreter (SCDO build split): EVMC interpreters exist only in CGO builds.
+func newEVMCInterpreter(evm *EVM, ewasm bool) Interpreter {
+	if ewasm {
+		return &EVMC{ewasmModule, evm, evmc.CapabilityEWASM, false}
+	}
+	return &EVMC{evmModule, evm, evmc.CapabilityEVM1, false}
+}
diff --git a/consensus/lyra2/lyra2_cgo.go b/consensus/lyra2/lyra2_cgo.go
new file mode 100644
index 0000000..6d6af8d
--- /dev/null
+++ b/consensus/lyra2/lyra2_cgo.go
@@ -0,0 +1,45 @@
+//go:build cgo
+
+package lyra2
+
+/*
+#cgo CFLAGS: -std=gnu99
+#include "Lyra2.h"
+#include <stdlib.h>
+*/
+import "C"
+import (
+	"encoding/binary"
+	"math/big"
+	"unsafe"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+func (lyra2 *Lyra2) calcHash(headerBytes []byte, nonce uint64, tcost int) *big.Int {
+	var lyra2_ctx unsafe.Pointer = C.LYRA2_create()
+	result := lyra2.compute(lyra2_ctx, headerBytes, nonce, tcost)
+	C.LYRA2_destroy(lyra2_ctx)
+
+	return result.Big()
+}
+
+func bytesToHash(in unsafe.Pointer) common.Hash {
+	return *(*common.Hash)(in)
+}
+
+func (lyra2 *Lyra2) compute(ctx unsafe.Pointer, blockBytes []byte, nonce uint64, tcost int) common.Hash {
+	binary.BigEndian.PutUint64(blockBytes[len(blockBytes)-8:], nonce)
+
+	var in unsafe.Pointer = C.CBytes(blockBytes)
+	var out unsafe.Pointer = C.malloc(common.HashLength)
+
+	C.LYRA2(ctx, out, common.HashLength, in, C.int32_t(len(blockBytes)), C.int32_t(tcost))
+
+	hash := bytesToHash(out)
+
+	C.free(in)
+	C.free(out)
+
+	return hash
+}
diff --git a/consensus/lyra2/lyra2_nocgo.go b/consensus/lyra2/lyra2_nocgo.go
new file mode 100644
index 0000000..83b477d
--- /dev/null
+++ b/consensus/lyra2/lyra2_nocgo.go
@@ -0,0 +1,18 @@
+//go:build !cgo
+
+// SCDO darwin/arm64 build (CGO_ENABLED=0): Lyra2 (MintMe) PoW hashing needs the C implementation.
+// It is not used by SCDO shard0 (Ethash); any Lyra2 seal fails verification in this build.
+package lyra2
+
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/log"
+)
+
+var maxHash = new(big.Int).Sub(new(big.Int).Lsh(big.NewInt(1), 256), big.NewInt(1))
+
+func (lyra2 *Lyra2) calcHash(headerBytes []byte, nonce uint64, tcost int) *big.Int {
+	log.Error("Lyra2 PoW is not available in this CGO-disabled build")
+	return new(big.Int).Set(maxHash)
+}
diff --git a/core/vm/evmc_nocgo.go b/core/vm/evmc_nocgo.go
new file mode 100644
index 0000000..763dd60
--- /dev/null
+++ b/core/vm/evmc_nocgo.go
@@ -0,0 +1,18 @@
+//go:build !cgo
+
+// SCDO darwin/arm64 build (CGO_ENABLED=0): external EVMC VMs (--vm.evm / --vm.ewasm) need cgo.
+// The built-in Go EVM (default) is unaffected.
+package vm
+
+import "github.com/ethereum/go-ethereum/log"
+
+func InitEVMCEVM(config string) {
+	log.Crit("EVMC (--vm.evm) is not supported in this CGO-disabled build")
+}
+func InitEVMCEwasm(config string) {
+	log.Crit("EVMC (--vm.ewasm) is not supported in this CGO-disabled build")
+}
+
+func newEVMCInterpreter(evm *EVM, ewasm bool) Interpreter {
+	panic("EVMC interpreters are not supported in this CGO-disabled build")
+}