diff --git a/nimbus/common/common.nim b/nimbus/common/common.nim
index 5cc25c3c6..7f933c830 100644
--- a/nimbus/common/common.nim
+++ b/nimbus/common/common.nim
@@ -357,7 +357,7 @@ proc consensus*(com: CommonRef, header: BlockHeader): ConsensusType =
 
 proc initializeEmptyDb*(com: CommonRef) =
   let kvt = com.db.newKvt()
-  proc contains(kvt: CoreDxKvtRef; key: openArray[byte]): bool =
+  proc contains(kvt: CoreDbKvtRef; key: openArray[byte]): bool =
     kvt.hasKey(key).expect "valid bool"
   if canonicalHeadHashKey().toOpenArray notin kvt:
     info "Writing genesis to DB"
diff --git a/nimbus/core/tx_pool/tx_tasks/tx_packer.nim b/nimbus/core/tx_pool/tx_tasks/tx_packer.nim
index fb5eec77b..43d5e5698 100644
--- a/nimbus/core/tx_pool/tx_tasks/tx_packer.nim
+++ b/nimbus/core/tx_pool/tx_tasks/tx_packer.nim
@@ -36,7 +36,7 @@ type
 
   TxPackerStateRef = ref object
     xp: TxPoolRef
-    tr: CoreDxMptRef
+    tr: CoreDbMptRef
     cleanState: bool
     balance: UInt256
     blobGasUsed: uint64
diff --git a/nimbus/db/core_db/backend/aristo_db.nim b/nimbus/db/core_db/backend/aristo_db.nim
index e532803e9..b2d0b0475 100644
--- a/nimbus/db/core_db/backend/aristo_db.nim
+++ b/nimbus/db/core_db/backend/aristo_db.nim
@@ -127,13 +127,13 @@ proc baseMethods(db: AristoCoreDbRef): CoreDbBaseFns =
     kBase = db.kdbBase
 
   when false: # currently disabled
-    proc tracerSetup(flags: set[CoreDbCaptFlags]): CoreDxCaptRef =
+    proc tracerSetup(flags: set[CoreDbCaptFlags]): CoreDbCaptRef =
       if db.tracer.isNil:
         db.tracer = AristoTracerRef(parent: db)
         db.tracer.init(kBase, aBase, flags)
       else:
         db.tracer.push(flags)
-      CoreDxCaptRef(methods: db.tracer.cptMethods)
+      CoreDbCaptRef(methods: db.tracer.cptMethods)
 
   proc persistent(bn: Opt[BlockNumber]): CoreDbRc[void] =
     const info = "persistentFn()"
@@ -164,7 +164,7 @@ proc baseMethods(db: AristoCoreDbRef): CoreDbBaseFns =
     errorPrintFn: proc(e: CoreDbErrorRef): string =
       e.errorPrint(),
 
-    newKvtFn: proc(): CoreDbRc[CoreDxKvtRef] =
+    newKvtFn: proc(): CoreDbRc[CoreDbKvtRef] =
       kBase.newKvtHandler("newKvtFn()"),
 
     newCtxFn: proc(): CoreDbCtxRef =
@@ -176,16 +176,16 @@ proc baseMethods(db: AristoCoreDbRef): CoreDbBaseFns =
     swapCtxFn: proc(ctx: CoreDbCtxRef): CoreDbCtxRef =
       aBase.swapCtx(ctx),
 
-    beginFn: proc(): CoreDxTxRef =
+    beginFn: proc(): CoreDbTxRef =
       const info = "beginFn()"
       let
         aTx = aBase.txBegin info
         kTx = kBase.txBegin info
-        dsc = CoreDxTxRef(methods: db.txMethods(aTx, kTx))
+        dsc = CoreDbTxRef(methods: db.txMethods(aTx, kTx))
       db.bless(dsc),
 
     # # currently disabled
-    #  newCaptureFn: proc(flags:set[CoreDbCaptFlags]): CoreDbRc[CoreDxCaptRef] =
+    #  newCaptureFn: proc(flags:set[CoreDbCaptFlags]): CoreDbRc[CoreDbCaptRef] =
     #    ok(db.bless flags.tracerSetup()),
 
     persistentFn: proc(bn: Opt[BlockNumber]): CoreDbRc[void] =
@@ -230,11 +230,11 @@ func toAristoProfData*(
       result.aristo = db.AristoCoreDbRef.adbBase.api.AristoApiProfRef.data
       result.kvt = db.AristoCoreDbRef.kdbBase.api.KvtApiProfRef.data
 
-func toAristoApi*(kvt: CoreDxKvtRef): KvtApiRef =
+func toAristoApi*(kvt: CoreDbKvtRef): KvtApiRef =
   if kvt.parent.isAristo:
     return AristoCoreDbRef(kvt.parent).kdbBase.api
 
-func toAristoApi*(mpt: CoreDxMptRef): AristoApiRef =
+func toAristoApi*(mpt: CoreDbMptRef): AristoApiRef =
   if mpt.parent.isAristo:
     return mpt.to(AristoApiRef)
 
@@ -264,7 +264,7 @@ include
 
 # ------------------------
 
-iterator aristoKvtPairsVoid*(dsc: CoreDxKvtRef): (Blob,Blob) {.rlpRaise.} =
+iterator aristoKvtPairsVoid*(dsc: CoreDbKvtRef): (Blob,Blob) {.rlpRaise.} =
   let
     api = dsc.toAristoApi()
     p = api.forkTx(dsc.to(KvtDbRef),0).valueOrApiError "aristoKvtPairs()"
@@ -272,7 +272,7 @@ iterator aristoKvtPairsVoid*(dsc: CoreDxKvtRef): (Blob,Blob) {.rlpRaise.} =
   for (k,v) in use_kvt.VoidBackendRef.walkPairs p:
     yield (k,v)
 
-iterator aristoKvtPairsMem*(dsc: CoreDxKvtRef): (Blob,Blob) {.rlpRaise.} =
+iterator aristoKvtPairsMem*(dsc: CoreDbKvtRef): (Blob,Blob) {.rlpRaise.} =
   let
     api = dsc.toAristoApi()
     p = api.forkTx(dsc.to(KvtDbRef),0).valueOrApiError "aristoKvtPairs()"
@@ -280,19 +280,19 @@ iterator aristoKvtPairsMem*(dsc: CoreDxKvtRef): (Blob,Blob) {.rlpRaise.} =
   for (k,v) in use_kvt.MemBackendRef.walkPairs p:
     yield (k,v)
 
-iterator aristoMptPairs*(dsc: CoreDxMptRef): (Blob,Blob) {.noRaise.} =
+iterator aristoMptPairs*(dsc: CoreDbMptRef): (Blob,Blob) {.noRaise.} =
   let
     api = dsc.to(AristoApiRef)
     mpt = dsc.to(AristoDbRef)
   for (k,v) in mpt.rightPairs LeafTie(root: dsc.rootID):
     yield (api.pathAsBlob(k.path), api.serialise(mpt, v).valueOr(EmptyBlob))
 
-iterator aristoReplicateMem*(dsc: CoreDxMptRef): (Blob,Blob) {.rlpRaise.} =
+iterator aristoReplicateMem*(dsc: CoreDbMptRef): (Blob,Blob) {.rlpRaise.} =
   ## Instantiation for `MemBackendRef`
   for k,v in aristoReplicate[use_ari.MemBackendRef](dsc):
     yield (k,v)
 
-iterator aristoReplicateVoid*(dsc: CoreDxMptRef): (Blob,Blob) {.rlpRaise.} =
+iterator aristoReplicateVoid*(dsc: CoreDbMptRef): (Blob,Blob) {.rlpRaise.} =
   ## Instantiation for `VoidBackendRef`
   for k,v in aristoReplicate[use_ari.VoidBackendRef](dsc):
     yield (k,v)
diff --git a/nimbus/db/core_db/backend/aristo_db/aristo_replicate.nim b/nimbus/db/core_db/backend/aristo_db/aristo_replicate.nim
index ffcefab8d..ae8116b25 100644
--- a/nimbus/db/core_db/backend/aristo_db/aristo_replicate.nim
+++ b/nimbus/db/core_db/backend/aristo_db/aristo_replicate.nim
@@ -20,7 +20,7 @@ template valueOrApiError[U,V](rc: Result[U,V]; info: static[string]): U =
   rc.valueOr: raise (ref AristoApiRlpError)(msg: info)
 
 iterator aristoReplicate[T](
-    dsc: CoreDxMptRef;
+    dsc: CoreDbMptRef;
       ): (Blob,Blob)
       {.gcsafe, raises: [AristoApiRlpError].} =
   ## Generic iterator used for building dedicated backend iterators.
diff --git a/nimbus/db/core_db/backend/aristo_db/handlers_aristo.nim b/nimbus/db/core_db/backend/aristo_db/handlers_aristo.nim
index 2dfd71fa5..5274d37a1 100644
--- a/nimbus/db/core_db/backend/aristo_db/handlers_aristo.nim
+++ b/nimbus/db/core_db/backend/aristo_db/handlers_aristo.nim
@@ -31,10 +31,10 @@ type
     base: AristoBaseRef          ## Local base descriptor
     mpt*: AristoDbRef            ## Aristo MPT database
 
-  AristoCoreDxAccRef = ref object of CoreDxAccRef
+  AristoCoreDbAccRef = ref object of CoreDbAccRef
     base: AristoBaseRef          ## Local base descriptor
 
-  AristoCoreDxMptRef = ref object of CoreDxMptRef
+  AristoCoreDbMptRef = ref object of CoreDbMptRef
     base: AristoBaseRef          ## Local base descriptor
     mptRoot: VertexID            ## State root, may be zero unless account
     accPath: PathID              ## Needed for storage tree/columns
@@ -94,7 +94,7 @@ func resetCol(colType: CoreDbColType): bool =
 # -------------------------------
 
 func toCoreDbAccount(
-    cAcc: AristoCoreDxAccRef;
+    cAcc: AristoCoreDbAccRef;
     acc: AristoAccount;
     address: EthAddress;
       ): CoreDbAccount =
@@ -184,7 +184,7 @@ func toVoidRc[T](
 # Private `MPT` call back functions
 # ------------------------------------------------------------------------------
 
-proc mptMethods(cMpt: AristoCoreDxMptRef): CoreDbMptFns =
+proc mptMethods(cMpt: AristoCoreDbMptRef): CoreDbMptFns =
   ## Generic columns database handlers
   let
     cMpt = cMpt        # So it can savely be captured
@@ -319,7 +319,7 @@ proc mptMethods(cMpt: AristoCoreDxMptRef): CoreDbMptFns =
 # Private account call back functions
 # ------------------------------------------------------------------------------
 
-proc accMethods(cAcc: AristoCoreDxAccRef): CoreDbAccFns =
+proc accMethods(cAcc: AristoCoreDbAccRef): CoreDbAccFns =
   ## Account columns database handlers
   let
     cAcc = cAcc        # So it can savely be captured
@@ -333,8 +333,8 @@ proc accMethods(cAcc: AristoCoreDxAccRef): CoreDbAccFns =
       base: base,
       colType: CtAccounts)
 
-  proc accCloneMpt(): CoreDbRc[CoreDxMptRef] =
-    var xpt = AristoCoreDxMptRef(
+  proc accCloneMpt(): CoreDbRc[CoreDbMptRef] =
+    var xpt = AristoCoreDbMptRef(
       base:    base,
       mptRoot: AccountsVID)
     xpt.methods = xpt.mptMethods
@@ -394,7 +394,7 @@ proc accMethods(cAcc: AristoCoreDxAccRef): CoreDbAccFns =
 
 
   CoreDbAccFns(
-    getMptFn: proc(): CoreDbRc[CoreDxMptRef] =
+    getMptFn: proc(): CoreDbRc[CoreDbMptRef] =
       accCloneMpt(),
 
     fetchFn: proc(address: EthAddress): CoreDbRc[CoreDbAccount] =
@@ -463,22 +463,22 @@ proc ctxMethods(cCtx: AristoCoreDbCtxRef): CoreDbCtxFns =
     err(aristo.GenericError.toError(base, info, RootNotFound))
 
 
-  proc ctxGetMpt(col: CoreDbColRef): CoreDbRc[CoreDxMptRef] =
+  proc ctxGetMpt(col: CoreDbColRef): CoreDbRc[CoreDbMptRef] =
     const
       info = "ctx/getMptFn()"
     let
       col = AristoColRef(col)
     var
       reset = false
-      newMpt: AristoCoreDxMptRef
+      newMpt: AristoCoreDbMptRef
     if not col.isValid:
       reset = true
-      newMpt = AristoCoreDxMptRef(
+      newMpt = AristoCoreDbMptRef(
         mptRoot: GenericVID,
         accPath: VOID_PATH_ID)
 
     elif col.colType == CtStorage:
-      newMpt = AristoCoreDxMptRef(
+      newMpt = AristoCoreDbMptRef(
         mptRoot: col.stoRoot,
         accPath: col.stoAddr.to(PathID),
         address: col.stoAddr)
@@ -492,7 +492,7 @@ proc ctxMethods(cCtx: AristoCoreDbCtxRef): CoreDbCtxFns =
           return err(rc.error[1].toError(base, info, AccNotFound))
     else:
       reset = col.colType.resetCol()
-      newMpt = AristoCoreDxMptRef(
+      newMpt = AristoCoreDbMptRef(
         mptRoot: VertexID(col.colType),
         accPath: VOID_PATH_ID)
 
@@ -508,7 +508,7 @@ proc ctxMethods(cCtx: AristoCoreDbCtxRef): CoreDbCtxFns =
     newMpt.methods = newMpt.mptMethods()
     ok(db.bless newMpt)
 
-  proc ctxGetAcc(col: CoreDbColRef): CoreDbRc[CoreDxAccRef] =
+  proc ctxGetAcc(col: CoreDbColRef): CoreDbRc[CoreDbAccRef] =
     const info = "getAccFn()"
 
     let col = AristoColRef(col)
@@ -516,7 +516,7 @@ proc ctxMethods(cCtx: AristoCoreDbCtxRef): CoreDbCtxFns =
       let error = (AccountsVID, AccRootUnacceptable)
       return err(error.toError(base, info, RootUnacceptable))
 
-    let acc = AristoCoreDxAccRef(base: base)
+    let acc = AristoCoreDbAccRef(base: base)
     acc.methods = acc.accMethods()
 
     ok(db.bless acc)
@@ -534,10 +534,10 @@ proc ctxMethods(cCtx: AristoCoreDbCtxRef): CoreDbCtxFns =
           ): CoreDbRc[CoreDbColRef] =
       ctxNewCol(col, colState, address),
 
-    getMptFn: proc(col: CoreDbColRef): CoreDbRc[CoreDxMptRef] =
+    getMptFn: proc(col: CoreDbColRef): CoreDbRc[CoreDbMptRef] =
       ctxGetMpt(col),
 
-    getAccFn: proc(col: CoreDbColRef): CoreDbRc[CoreDxAccRef] =
+    getAccFn: proc(col: CoreDbColRef): CoreDbRc[CoreDbAccRef] =
       ctxGetAcc(col),
 
     forgetFn: proc() =
@@ -579,14 +579,14 @@ proc getSavedState*(base: AristoBaseRef): Result[SavedState,void] =
 
 # ---------------------
 
-func to*(dsc: CoreDxMptRef, T: type AristoDbRef): T =
-  AristoCoreDxMptRef(dsc).base.ctx.mpt
+func to*(dsc: CoreDbMptRef, T: type AristoDbRef): T =
+  AristoCoreDbMptRef(dsc).base.ctx.mpt
 
-func to*(dsc: CoreDxMptRef, T: type AristoApiRef): T =
-  AristoCoreDxMptRef(dsc).base.api
+func to*(dsc: CoreDbMptRef, T: type AristoApiRef): T =
+  AristoCoreDbMptRef(dsc).base.api
 
-func rootID*(dsc: CoreDxMptRef): VertexID  =
-  AristoCoreDxMptRef(dsc).mptRoot
+func rootID*(dsc: CoreDbMptRef): VertexID  =
+  AristoCoreDbMptRef(dsc).mptRoot
 
 func txTop*(
     base: AristoBaseRef;
diff --git a/nimbus/db/core_db/backend/aristo_db/handlers_kvt.nim b/nimbus/db/core_db/backend/aristo_db/handlers_kvt.nim
index 71816d753..eb0578381 100644
--- a/nimbus/db/core_db/backend/aristo_db/handlers_kvt.nim
+++ b/nimbus/db/core_db/backend/aristo_db/handlers_kvt.nim
@@ -24,9 +24,9 @@ type
     parent: CoreDbRef            ## Opaque top level descriptor
     kdb: KvtDbRef                ## Shared key-value table
     api*: KvtApiRef              ## Api functions can be re-directed
-    cache: KvtCoreDxKvtRef       ## Shared transaction table wrapper
+    cache: KvtCoreDbKvtRef       ## Shared transaction table wrapper
 
-  KvtCoreDxKvtRef = ref object of CoreDxKvtRef
+  KvtCoreDbKvtRef = ref object of CoreDbKvtRef
     base: KvtBaseRef             ## Local base descriptor
     kvt: KvtDbRef                ## In most cases different from `base.kdb`
 
@@ -68,16 +68,16 @@ func toRc[T](
 # Private `kvt` call back functions
 # ------------------------------------------------------------------------------
 
-proc kvtMethods(cKvt: KvtCoreDxKvtRef): CoreDbKvtFns =
+proc kvtMethods(cKvt: KvtCoreDbKvtRef): CoreDbKvtFns =
   ## Key-value database table handlers
 
   proc kvtBackend(
-      cKvt:KvtCoreDxKvtRef;
+      cKvt:KvtCoreDbKvtRef;
         ): CoreDbKvtBackendRef =
     cKvt.base.parent.bless AristoCoreDbKvtBE(kdb: cKvt.kvt)
 
   proc kvtForget(
-      cKvt: KvtCoreDxKvtRef;
+      cKvt: KvtCoreDbKvtRef;
       info: static[string];
         ): CoreDbRc[void] =
     let
@@ -95,7 +95,7 @@ proc kvtMethods(cKvt: KvtCoreDxKvtRef): CoreDbKvtFns =
     ok()
 
   proc kvtGet(
-      cKvt: KvtCoreDxKvtRef;
+      cKvt: KvtCoreDbKvtRef;
       k: openArray[byte];
       info: static[string];
         ): CoreDbRc[Blob] =
@@ -108,7 +108,7 @@ proc kvtMethods(cKvt: KvtCoreDxKvtRef): CoreDbKvtFns =
       rc.toRc(cKvt.base, info)
 
   proc kvtPut(
-      cKvt: KvtCoreDxKvtRef;
+      cKvt: KvtCoreDbKvtRef;
       k: openArray[byte];
       v: openArray[byte];
       info: static[string];
@@ -120,7 +120,7 @@ proc kvtMethods(cKvt: KvtCoreDxKvtRef): CoreDbKvtFns =
       err(rc.error.toError(cKvt.base, info))
 
   proc kvtDel(
-      cKvt: KvtCoreDxKvtRef;
+      cKvt: KvtCoreDbKvtRef;
       k: openArray[byte];
       info: static[string];
         ): CoreDbRc[void] =
@@ -131,7 +131,7 @@ proc kvtMethods(cKvt: KvtCoreDxKvtRef): CoreDbKvtFns =
       err(rc.error.toError(cKvt.base, info))
 
   proc kvtHasKey(
-      cKvt: KvtCoreDxKvtRef;
+      cKvt: KvtCoreDbKvtRef;
       k: openArray[byte];
       info: static[string];
         ): CoreDbRc[bool] =
@@ -176,8 +176,8 @@ func toVoidRc*[T](
 
 # ---------------------
 
-func to*(dsc: CoreDxKvtRef; T: type KvtDbRef): T =
-  KvtCoreDxKvtRef(dsc).kvt
+func to*(dsc: CoreDbKvtRef; T: type KvtDbRef): T =
+  KvtCoreDbKvtRef(dsc).kvt
 
 func txTop*(
     base: KvtBaseRef;
@@ -219,7 +219,7 @@ proc persistent*(
 proc newKvtHandler*(
     base: KvtBaseRef;
     info: static[string];
-      ): CoreDbRc[CoreDxKvtRef] =
+      ): CoreDbRc[CoreDbKvtRef] =
     ok(base.cache)
 
 
@@ -234,7 +234,7 @@ func init*(T: type KvtBaseRef; db: CoreDbRef; kdb: KvtDbRef): T =
     kdb:    kdb)
 
   # Preallocated shared descriptor
-  let dsc = KvtCoreDxKvtRef(
+  let dsc = KvtCoreDbKvtRef(
     base: result,
     kvt:  kdb)
   dsc.methods = dsc.kvtMethods()
diff --git a/nimbus/db/core_db/backend/aristo_rocksdb.nim b/nimbus/db/core_db/backend/aristo_rocksdb.nim
index 21e3d2e55..0ae4d33a6 100644
--- a/nimbus/db/core_db/backend/aristo_rocksdb.nim
+++ b/nimbus/db/core_db/backend/aristo_rocksdb.nim
@@ -170,7 +170,7 @@ proc newAristoDualRocksDbCoreDbRef*(path: string, opts: DbOptions): CoreDbRef =
 # Public aristo iterators
 # ------------------------------------------------------------------------------
 
-iterator aristoReplicateRdb*(dsc: CoreDxMptRef): (Blob, Blob) {.rlpRaise.} =
+iterator aristoReplicateRdb*(dsc: CoreDbMptRef): (Blob, Blob) {.rlpRaise.} =
   ## Instantiation for `VoidBackendRef`
   for k, v in aristoReplicate[use_ari.RdbBackendRef](dsc):
     yield (k, v)
diff --git a/nimbus/db/core_db/base.nim b/nimbus/db/core_db/base.nim
index 28e60a760..1a79639c3 100644
--- a/nimbus/db/core_db/base.nim
+++ b/nimbus/db/core_db/base.nim
@@ -23,7 +23,7 @@ const
   EnableApiTracking = false
     ## When enabled, functions using this tracking facility need to import
     ## `chronicles`, as well. Tracking is enabled by setting `true` the flags
-    ## `trackLegaApi` and/or `trackNewApi` in the `CoreDxTxRef` descriptor.
+    ## `trackLegaApi` and/or `trackNewApi` in the `CoreDbTxRef` descriptor.
 
   EnableApiProfiling = true
     ## Enables functions profiling if `EnableApiTracking` is also set `true`.
@@ -49,12 +49,11 @@ export
   CoreDbProfListRef,
   CoreDbRef,
   CoreDbType,
-  CoreDxAccRef,
-  CoreDxCaptRef,
-  CoreDxKvtRef,
-  CoreDxMptRef,
-  CoreDxPhkRef,
-  CoreDxTxRef,
+  CoreDbAccRef,
+  CoreDbCaptRef,
+  CoreDbKvtRef,
+  CoreDbMptRef,
+  CoreDbTxRef,
   PayloadRef
 
 const
@@ -94,7 +93,7 @@ when EnableApiTracking:
   proc `$`(h: Hash256): string = h.toStr
 
 template setTrackNewApi(
-    w: CoreDxApiTrackRef;
+    w: CoreDbApiTrackRef;
     s: static[CoreDbFnInx];
     code: untyped;
       ) =
@@ -106,48 +105,17 @@ template setTrackNewApi(
   const api {.inject,used.} = s
 
 template setTrackNewApi*(
-    w: CoreDxApiTrackRef;
+    w: CoreDbApiTrackRef;
     s: static[CoreDbFnInx];
       ) =
   w.setTrackNewApi(s):
     discard
 
-template ifTrackNewApi*(w: CoreDxApiTrackRef; code: untyped) =
+template ifTrackNewApi*(w: CoreDbApiTrackRef; code: untyped) =
   when EnableApiTracking:
     w.endNewApiIf:
       code
 
-# ---------
-
-func toCoreDxPhkRef(mpt: CoreDxMptRef): CoreDxPhkRef =
-  ## MPT => pre-hashed MPT (aka PHK)
-  result = CoreDxPhkRef(
-    toMpt: mpt,
-    methods: mpt.methods)
-
-  result.methods.fetchFn =
-    proc(k: openArray[byte]): CoreDbRc[Blob] =
-      mpt.methods.fetchFn(k.keccakHash.data)
-
-  result.methods.deleteFn =
-    proc(k: openArray[byte]): CoreDbRc[void] =
-      mpt.methods.deleteFn(k.keccakHash.data)
-
-  result.methods.mergeFn =
-    proc(k:openArray[byte]; v: openArray[byte]): CoreDbRc[void] =
-      mpt.methods.mergeFn(k.keccakHash.data, v)
-
-  result.methods.hasPathFn =
-    proc(k: openArray[byte]): CoreDbRc[bool] =
-      mpt.methods.hasPathFn(k.keccakHash.data)
-
-  when AutoValidateDescriptors:
-    result.validate
-
-
-func parent(phk: CoreDxPhkRef): CoreDbRef =
-  phk.toMpt.parent
-
 # ------------------------------------------------------------------------------
 # Public constructor helper
 # ------------------------------------------------------------------------------
@@ -168,16 +136,16 @@ proc bless*(db: CoreDbRef; col: CoreDbColRef): CoreDbColRef =
     col.validate
   col
 
-proc bless*(db: CoreDbRef; kvt: CoreDxKvtRef): CoreDxKvtRef =
+proc bless*(db: CoreDbRef; kvt: CoreDbKvtRef): CoreDbKvtRef =
   ## Complete sub-module descriptor, fill in `parent`.
   kvt.parent = db
   when AutoValidateDescriptors:
     kvt.validate
   kvt
 
-proc bless*[T: CoreDxKvtRef |
-               CoreDbCtxRef | CoreDxMptRef | CoreDxPhkRef | CoreDxAccRef |
-               CoreDxTxRef  | CoreDxCaptRef |
+proc bless*[T: CoreDbKvtRef |
+               CoreDbCtxRef | CoreDbMptRef | CoreDbAccRef |
+               CoreDbTxRef  | CoreDbCaptRef |
                CoreDbKvtBackendRef | CoreDbMptBackendRef](
     db: CoreDbRef;
     dsc: T;
@@ -226,18 +194,18 @@ proc dbType*(db: CoreDbRef): CoreDbType =
   result = db.dbType
   db.ifTrackNewApi: debug newApiTxt, api, elapsed, result
 
-proc parent*[T: CoreDxKvtRef |
+proc parent*[T: CoreDbKvtRef |
                 CoreDbColRef |
-                CoreDbCtxRef | CoreDxMptRef | CoreDxPhkRef | CoreDxAccRef |
-                CoreDxTxRef |
-                CoreDxCaptRef |
+                CoreDbCtxRef | CoreDbMptRef | CoreDbAccRef |
+                CoreDbTxRef |
+                CoreDbCaptRef |
                 CoreDbErrorRef](
     child: T): CoreDbRef =
   ## Getter, common method for all sub-modules
   ##
   result = child.parent
 
-proc backend*(dsc: CoreDxKvtRef | CoreDxMptRef): auto =
+proc backend*(dsc: CoreDbKvtRef | CoreDbMptRef): auto =
   ## Getter, retrieves the *raw* backend object for special/localised support.
   ##
   dsc.setTrackNewApi AnyBackendFn
@@ -268,7 +236,7 @@ proc `$$`*(e: CoreDbErrorRef): string =
 # Public key-value table methods
 # ------------------------------------------------------------------------------
 
-proc newKvt*(db: CoreDbRef): CoreDxKvtRef =
+proc newKvt*(db: CoreDbRef): CoreDbKvtRef =
   ## Constructor, will defect on failure.
   ##
   ## This function subscribes to the common base object shared with other
@@ -281,13 +249,13 @@ proc newKvt*(db: CoreDbRef): CoreDxKvtRef =
     raiseAssert error.prettyText()
   db.ifTrackNewApi: debug newApiTxt, api, elapsed
 
-proc get*(kvt: CoreDxKvtRef; key: openArray[byte]): CoreDbRc[Blob] =
+proc get*(kvt: CoreDbKvtRef; key: openArray[byte]): CoreDbRc[Blob] =
   ## This function always returns a non-empty `Blob` or an error code.
   kvt.setTrackNewApi KvtGetFn
   result = kvt.methods.getFn key
   kvt.ifTrackNewApi: debug newApiTxt, api, elapsed, key=key.toStr, result
 
-proc getOrEmpty*(kvt: CoreDxKvtRef; key: openArray[byte]): CoreDbRc[Blob] =
+proc getOrEmpty*(kvt: CoreDbKvtRef; key: openArray[byte]): CoreDbRc[Blob] =
   ## This function sort of mimics the behaviour of the legacy database
   ## returning an empty `Blob` if the argument `key` is not found on the
   ## database.
@@ -298,13 +266,13 @@ proc getOrEmpty*(kvt: CoreDxKvtRef; key: openArray[byte]): CoreDbRc[Blob] =
     result = CoreDbRc[Blob].ok(EmptyBlob)
   kvt.ifTrackNewApi: debug newApiTxt, api, elapsed, key=key.toStr, result
 
-proc del*(kvt: CoreDxKvtRef; key: openArray[byte]): CoreDbRc[void] =
+proc del*(kvt: CoreDbKvtRef; key: openArray[byte]): CoreDbRc[void] =
   kvt.setTrackNewApi KvtDelFn
   result = kvt.methods.delFn key
   kvt.ifTrackNewApi: debug newApiTxt, api, elapsed, key=key.toStr, result
 
 proc put*(
-    kvt: CoreDxKvtRef;
+    kvt: CoreDbKvtRef;
     key: openArray[byte];
     val: openArray[byte];
       ): CoreDbRc[void] =
@@ -313,7 +281,7 @@ proc put*(
   kvt.ifTrackNewApi:
     debug newApiTxt, api, elapsed, key=key.toStr, val=val.toLenStr, result
 
-proc hasKey*(kvt: CoreDxKvtRef; key: openArray[byte]): CoreDbRc[bool] =
+proc hasKey*(kvt: CoreDbKvtRef; key: openArray[byte]): CoreDbRc[bool] =
   ## Would be named `contains` if it returned `bool` rather than `Result[]`.
   ##
   kvt.setTrackNewApi KvtHasKeyFn
@@ -400,7 +368,7 @@ proc newColumn*(
   ##
   ## This function is intended to open a column on the database as in:
   ## ::
-  ##   proc openAccountLedger(db: CoreDbRef, colState: Hash256): CoreDxMptRef =
+  ##   proc openAccountLedger(db: CoreDbRef, colState: Hash256): CoreDbMptRef =
   ##     let col = db.ctx.newColumn(CtAccounts, colState).valueOr:
   ##       # some error handling
   ##       return
@@ -490,7 +458,7 @@ proc stateEmptyOrVoid*(col: CoreDbColRef): bool =
 proc getMpt*(
     ctx: CoreDbCtxRef;
     col: CoreDbColRef;
-      ): CoreDbRc[CoreDxMptRef] =
+      ): CoreDbRc[CoreDbMptRef] =
   ## Get an MPT sub-trie view.
   ##
   ## If the `col` argument descriptor was created for an `EMPTY_ROOT_HASH`
@@ -507,7 +475,7 @@ proc getMpt*(
     ctx: CoreDbCtxRef;
     colType: CoreDbColType;
     address = Opt.none(EthAddress);
-      ): CoreDxMptRef =
+      ): CoreDbMptRef =
   ## Shortcut for `getMpt(col)` where the `col` argument is
   ## `db.getColumn(colType,EMPTY_ROOT_HASH).value`. This function will always
   ## return a non-nil descriptor or throw an exception.
@@ -519,7 +487,7 @@ proc getMpt*(
   ctx.ifTrackNewApi: debug newApiTxt, api, colType, elapsed
 
 
-proc getMpt*(acc: CoreDxAccRef): CoreDxMptRef =
+proc getMpt*(acc: CoreDbAccRef): CoreDbMptRef =
   ## Variant of `getMpt()`, will defect on failure.
   ##
   ## The needed sub-trie information is taken/implied from the current `acc`
@@ -536,7 +504,7 @@ proc getMpt*(acc: CoreDxAccRef): CoreDxMptRef =
 proc getAcc*(
     ctx: CoreDbCtxRef;
     col: CoreDbColRef;
-      ): CoreDbRc[CoreDxAccRef] =
+      ): CoreDbRc[CoreDbAccRef] =
   ## Accounts trie constructor, will defect on failure.
   ##
   ## Example:
@@ -549,62 +517,35 @@ proc getAcc*(
   ##     ... # Was not the state root for the accounts column
   ##     return
   ##
-  ## This function works similar to `getMpt()` for handling accounts. Although
-  ## one can emulate this function by means of `getMpt(..).toPhk()`, it is
-  ## recommended using `CoreDxAccRef` methods for accounts.
+  ## This function works similar to `getMpt()` for handling accounts.
   ##
   ctx.setTrackNewApi CtxGetAccFn
   result = ctx.methods.getAccFn col
   ctx.ifTrackNewApi: debug newApiTxt, api, elapsed, col, result
 
-proc toMpt*(phk: CoreDxPhkRef): CoreDxMptRef =
-  ## Replaces the pre-hashed argument column `phk` by the non pre-hashed *MPT*.
-  ##
-  phk.setTrackNewApi PhkToMptFn
-  result = phk.toMpt
-  phk.ifTrackNewApi:
-    let col = result.methods.getColFn()
-    debug newApiTxt, api, elapsed, col
-
-proc toPhk*(mpt: CoreDxMptRef): CoreDxPhkRef =
-  ## Replaces argument `mpt` by a pre-hashed *MPT*.
-  ##
-  mpt.setTrackNewApi MptToPhkFn
-  result = mpt.toCoreDxPhkRef
-  mpt.ifTrackNewApi:
-    let col = result.methods.getColFn()
-    debug newApiTxt, api, elapsed, col
-
 # ------------------------------------------------------------------------------
-# Public common methods for all hexary trie databases (`mpt`, `phk`, or `acc`)
+# Public common methods for all hexary trie databases (`mpt`, or `acc`)
 # ------------------------------------------------------------------------------
 
-proc getColumn*(acc: CoreDxAccRef): CoreDbColRef =
+proc getColumn*(acc: CoreDbAccRef): CoreDbColRef =
   ## Getter, result is not `nil`
   ##
   acc.setTrackNewApi AccGetColFn
   result = acc.methods.getColFn()
   acc.ifTrackNewApi: debug newApiTxt, api, elapsed, result
 
-proc getColumn*(mpt: CoreDxMptRef): CoreDbColRef =
+proc getColumn*(mpt: CoreDbMptRef): CoreDbColRef =
   ## Variant of `getColumn()`
   ##
   mpt.setTrackNewApi MptGetColFn
   result = mpt.methods.getColFn()
   mpt.ifTrackNewApi: debug newApiTxt, api, elapsed, result
 
-proc getColumn*(phk: CoreDxPhkRef): CoreDbColRef =
-  ## Variant of `getColumn()`
-  ##
-  phk.setTrackNewApi PhkGetColFn
-  result = phk.methods.getColFn()
-  phk.ifTrackNewApi: debug newApiTxt, api, elapsed, result
-
 # ------------------------------------------------------------------------------
-# Public generic hexary trie database methods (`mpt` or `phk`)
+# Public generic hexary trie database methods
 # ------------------------------------------------------------------------------
 
-proc fetch*(mpt: CoreDxMptRef; key: openArray[byte]): CoreDbRc[Blob] =
+proc fetch*(mpt: CoreDbMptRef; key: openArray[byte]): CoreDbRc[Blob] =
   ## Fetch data from the argument `mpt`. The function always returns a
   ## non-empty `Blob` or an error code.
   ##
@@ -614,16 +555,7 @@ proc fetch*(mpt: CoreDxMptRef; key: openArray[byte]): CoreDbRc[Blob] =
     let col = mpt.methods.getColFn()
     debug newApiTxt, api, elapsed, col, key=key.toStr, result
 
-proc fetch*(phk: CoreDxPhkRef; key: openArray[byte]): CoreDbRc[Blob] =
-  ## Variant of `fetch()"
-  phk.setTrackNewApi PhkFetchFn
-  result = phk.methods.fetchFn key
-  phk.ifTrackNewApi:
-    let col = phk.methods.getColFn()
-    debug newApiTxt, api, elapsed, col, key=key.toStr, result
-
-
-proc fetchOrEmpty*(mpt: CoreDxMptRef; key: openArray[byte]): CoreDbRc[Blob] =
+proc fetchOrEmpty*(mpt: CoreDbMptRef; key: openArray[byte]): CoreDbRc[Blob] =
   ## This function returns an empty `Blob` if the argument `key` is not found
   ## on the database.
   ##
@@ -635,34 +567,15 @@ proc fetchOrEmpty*(mpt: CoreDxMptRef; key: openArray[byte]): CoreDbRc[Blob] =
     let col = mpt.methods.getColFn()
     debug newApiTxt, api, elapsed, col, key=key.toStr, result
 
-proc fetchOrEmpty*(phk: CoreDxPhkRef; key: openArray[byte]): CoreDbRc[Blob] =
-  ## Variant of `fetchOrEmpty()`
-  phk.setTrackNewApi PhkFetchOrEmptyFn
-  result = phk.methods.fetchFn key
-  if result.isErr and result.error.error == MptNotFound:
-    result = CoreDbRc[Blob].ok(EmptyBlob)
-  phk.ifTrackNewApi:
-    let col = phk.methods.getColFn()
-    debug newApiTxt, api, elapsed, col, key=key.toStr, result
-
-
-proc delete*(mpt: CoreDxMptRef; key: openArray[byte]): CoreDbRc[void] =
+proc delete*(mpt: CoreDbMptRef; key: openArray[byte]): CoreDbRc[void] =
   mpt.setTrackNewApi MptDeleteFn
   result = mpt.methods.deleteFn key
   mpt.ifTrackNewApi:
     let col = mpt.methods.getColFn()
     debug newApiTxt, api, elapsed, col, key=key.toStr, result
 
-proc delete*(phk: CoreDxPhkRef; key: openArray[byte]): CoreDbRc[void] =
-  phk.setTrackNewApi PhkDeleteFn
-  result = phk.methods.deleteFn key
-  phk.ifTrackNewApi:
-    let col = phk.methods.getColFn()
-    debug newApiTxt, api, elapsed, col, key=key.toStr, result
-
-
 proc merge*(
-    mpt: CoreDxMptRef;
+    mpt: CoreDbMptRef;
     key: openArray[byte];
     val: openArray[byte];
       ): CoreDbRc[void] =
@@ -672,19 +585,7 @@ proc merge*(
     let col = mpt.methods.getColFn()
     debug newApiTxt, api, elapsed, col, key=key.toStr, val=val.toLenStr, result
 
-proc merge*(
-    phk: CoreDxPhkRef;
-    key: openArray[byte];
-    val: openArray[byte];
-      ): CoreDbRc[void] =
-  phk.setTrackNewApi PhkMergeFn
-  result = phk.methods.mergeFn(key, val)
-  phk.ifTrackNewApi:
-    let col = phk.methods.getColFn()
-    debug newApiTxt, api, elapsed, col, key=key.toStr, val=val.toLenStr, result
-
-
-proc hasPath*(mpt: CoreDxMptRef; key: openArray[byte]): CoreDbRc[bool] =
+proc hasPath*(mpt: CoreDbMptRef; key: openArray[byte]): CoreDbRc[bool] =
   ## This function would be named `contains()` if it returned `bool` rather
   ## than a `Result[]`.
   ##
@@ -694,19 +595,11 @@ proc hasPath*(mpt: CoreDxMptRef; key: openArray[byte]): CoreDbRc[bool] =
     let col = mpt.methods.getColFn()
     debug newApiTxt, api, elapsed, col, key=key.toStr, result
 
-proc hasPath*(phk: CoreDxPhkRef; key: openArray[byte]): CoreDbRc[bool] =
-  ## Variant of `hasPath()`
-  phk.setTrackNewApi PhkHasPathFn
-  result = phk.methods.hasPathFn key
-  phk.ifTrackNewApi:
-    let col = phk.methods.getColFn()
-    debug newApiTxt, api, elapsed, col, key=key.toStr, result
-
 # ------------------------------------------------------------------------------
 # Public trie database methods for accounts
 # ------------------------------------------------------------------------------
 
-proc fetch*(acc: CoreDxAccRef; address: EthAddress): CoreDbRc[CoreDbAccount] =
+proc fetch*(acc: CoreDbAccRef; address: EthAddress): CoreDbRc[CoreDbAccount] =
   ## Fetch data from the argument `acc`.
   ##
   acc.setTrackNewApi AccFetchFn
@@ -716,12 +609,12 @@ proc fetch*(acc: CoreDxAccRef; address: EthAddress): CoreDbRc[CoreDbAccount] =
     debug newApiTxt, api, elapsed, address, storage, result
 
 
-proc delete*(acc: CoreDxAccRef; address: EthAddress): CoreDbRc[void] =
+proc delete*(acc: CoreDbAccRef; address: EthAddress): CoreDbRc[void] =
   acc.setTrackNewApi AccDeleteFn
   result = acc.methods.deleteFn address
   acc.ifTrackNewApi: debug newApiTxt, api, elapsed, address, result
 
-proc stoDelete*(acc: CoreDxAccRef; address: EthAddress): CoreDbRc[void] =
+proc stoDelete*(acc: CoreDbAccRef; address: EthAddress): CoreDbRc[void] =
   ## Recursively delete all data elements from the storage trie associated to
   ## the account identified by the argument `address`. After successful run,
   ## the storage trie will be empty.
@@ -738,7 +631,7 @@ proc stoDelete*(acc: CoreDxAccRef; address: EthAddress): CoreDbRc[void] =
 
 
 proc merge*(
-    acc: CoreDxAccRef;
+    acc: CoreDbAccRef;
     account: CoreDbAccount;
       ): CoreDbRc[void] =
   acc.setTrackNewApi AccMergeFn
@@ -748,7 +641,7 @@ proc merge*(
     debug newApiTxt, api, elapsed, address, result
 
 
-proc hasPath*(acc: CoreDxAccRef; address: EthAddress): CoreDbRc[bool] =
+proc hasPath*(acc: CoreDbAccRef; address: EthAddress): CoreDbRc[bool] =
   ## Would be named `contains` if it returned `bool` rather than `Result[]`.
   ##
   acc.setTrackNewApi AccHasPathFn
@@ -835,7 +728,7 @@ proc persistent*(
   result = db.methods.persistentFn Opt.some(blockNumber)
   db.ifTrackNewApi: debug newApiTxt, api, elapsed, blockNumber, result
 
-proc newTransaction*(db: CoreDbRef): CoreDxTxRef =
+proc newTransaction*(db: CoreDbRef): CoreDbTxRef =
   ## Constructor
   ##
   db.setTrackNewApi BaseNewTxFn
@@ -844,26 +737,26 @@ proc newTransaction*(db: CoreDbRef): CoreDxTxRef =
     debug newApiTxt, api, elapsed, newLevel=db.methods.levelFn()
 
 
-proc level*(tx: CoreDxTxRef): int =
+proc level*(tx: CoreDbTxRef): int =
   ## Print positive transaction level for argument `tx`
   ##
   tx.setTrackNewApi TxLevelFn
   result = tx.methods.levelFn()
   tx.ifTrackNewApi: debug newApiTxt, api, elapsed, result
 
-proc commit*(tx: CoreDxTxRef) =
+proc commit*(tx: CoreDbTxRef) =
   tx.setTrackNewApi TxCommitFn:
     let prvLevel {.used.} = tx.methods.levelFn()
   tx.methods.commitFn()
   tx.ifTrackNewApi: debug newApiTxt, api, elapsed, prvLevel
 
-proc rollback*(tx: CoreDxTxRef) =
+proc rollback*(tx: CoreDbTxRef) =
   tx.setTrackNewApi TxRollbackFn:
     let prvLevel {.used.} = tx.methods.levelFn()
   tx.methods.rollbackFn()
   tx.ifTrackNewApi: debug newApiTxt, api, elapsed, prvLevel
 
-proc dispose*(tx: CoreDxTxRef) =
+proc dispose*(tx: CoreDbTxRef) =
   tx.setTrackNewApi TxDisposeFn:
     let prvLevel {.used.} = tx.methods.levelFn()
   tx.methods.disposeFn()
@@ -877,7 +770,7 @@ when false: # currently disabled
   proc newCapture*(
       db: CoreDbRef;
       flags: set[CoreDbCaptFlags] = {};
-        ): CoreDbRc[CoreDxCaptRef] =
+        ): CoreDbRc[CoreDbCaptRef] =
     ## Trace constructor providing an overlay on top of the argument database
     ## `db`. This overlay provides a replacement database handle that can be
     ## retrieved via `db.recorder()` (which can in turn be ovelayed.) While
@@ -893,7 +786,7 @@ when false: # currently disabled
     result = db.methods.newCaptureFn flags
     db.ifTrackNewApi: debug newApiTxt, api, elapsed, result
 
-  proc recorder*(cpt: CoreDxCaptRef): CoreDbRef =
+  proc recorder*(cpt: CoreDbCaptRef): CoreDbRef =
     ## Getter, returns a tracer replacement handle to be used as new database.
     ## It records every action like fetch, store, hasKey, hasPath and delete.
     ## This descriptor can be superseded by a new overlay tracer (using
@@ -908,7 +801,7 @@ when false: # currently disabled
     result = cpt.methods.recorderFn()
     cpt.ifTrackNewApi: debug newApiTxt, api, elapsed
 
-  proc logDb*(cp: CoreDxCaptRef): TableRef[Blob,Blob] =
+  proc logDb*(cp: CoreDbCaptRef): TableRef[Blob,Blob] =
     ## Getter, returns the logger table for the overlay tracer database.
     ##
     ## Caveat:
@@ -920,14 +813,14 @@ when false: # currently disabled
     result = cp.methods.logDbFn()
     cp.ifTrackNewApi: debug newApiTxt, api, elapsed
 
-  proc flags*(cp: CoreDxCaptRef):set[CoreDbCaptFlags] =
+  proc flags*(cp: CoreDbCaptRef):set[CoreDbCaptFlags] =
     ## Getter
     ##
     cp.setTrackNewApi CptFlagsFn
     result = cp.methods.getFlagsFn()
     cp.ifTrackNewApi: debug newApiTxt, api, elapsed, result
 
-  proc forget*(cp: CoreDxCaptRef) =
+  proc forget*(cp: CoreDbCaptRef) =
     ## Explicitely stop recording the current tracer instance and reset to
     ## previous level.
     ##
diff --git a/nimbus/db/core_db/base/api_tracking.nim b/nimbus/db/core_db/base/api_tracking.nim
index 29c4d180b..4567e647f 100644
--- a/nimbus/db/core_db/base/api_tracking.nim
+++ b/nimbus/db/core_db/base/api_tracking.nim
@@ -19,10 +19,10 @@ import
   ./base_desc
 
 type
-  CoreDxApiTrackRef* =
-    CoreDbRef | CoreDxKvtRef | CoreDbColRef |
-    CoreDbCtxRef | CoreDxMptRef | CoreDxPhkRef | CoreDxAccRef |
-    CoreDxTxRef | CoreDxCaptRef | CoreDbErrorRef
+  CoreDbApiTrackRef* =
+    CoreDbRef | CoreDbKvtRef | CoreDbColRef |
+    CoreDbCtxRef | CoreDbMptRef | CoreDbAccRef |
+    CoreDbTxRef | CoreDbCaptRef | CoreDbErrorRef
 
   CoreDbFnInx* = enum
     ## Profiling table index
@@ -84,16 +84,6 @@ type
     MptMergeFn          = "mpt/merge"
     MptPairsIt          = "mpt/pairs"
     MptReplicateIt      = "mpt/replicate"
-    MptToPhkFn          = "mpt/toPhk"
-
-    PhkDeleteFn         = "phk/delete"
-    PhkFetchFn          = "phk/fetch"
-    PhkFetchOrEmptyFn   = "phk/fetchOrEmpty"
-    PhkForgetFn         = "phk/forget"
-    PhkGetColFn         = "phk/getColumn"
-    PhkHasPathFn        = "phk/hasPath"
-    PhkMergeFn          = "phk/merge"
-    PhkToMptFn          = "phk/toMpt"
 
     TxCommitFn          = "commit"
     TxDisposeFn         = "dispose"
@@ -165,12 +155,12 @@ proc toStr[T](rc: CoreDbRc[T]; ifOk: static[string]): string =
 
 proc toStr*(rc: CoreDbRc[CoreDbRef]): string = rc.toStr "db"
 proc toStr*(rc: CoreDbRc[CoreDbAccount]): string = rc.toStr "acc"
-proc toStr*(rc: CoreDbRc[CoreDxKvtRef]): string = rc.toStr "kvt"
-proc toStr*(rc: CoreDbRc[CoreDxTxRef]): string = rc.toStr "tx"
-proc toStr*(rc: CoreDbRc[CoreDxCaptRef]): string = rc.toStr "capt"
+proc toStr*(rc: CoreDbRc[CoreDbKvtRef]): string = rc.toStr "kvt"
+proc toStr*(rc: CoreDbRc[CoreDbTxRef]): string = rc.toStr "tx"
+proc toStr*(rc: CoreDbRc[CoreDbCaptRef]): string = rc.toStr "capt"
 proc toStr*(rc: CoreDbRc[CoreDbCtxRef]): string = rc.toStr "ctx"
-proc toStr*(rc: CoreDbRc[CoreDxMptRef]): string = rc.toStr "mpt"
-proc toStr*(rc: CoreDbRc[CoreDxAccRef]): string = rc.toStr "acc"
+proc toStr*(rc: CoreDbRc[CoreDbMptRef]): string = rc.toStr "mpt"
+proc toStr*(rc: CoreDbRc[CoreDbAccRef]): string = rc.toStr "acc"
 
 func toStr*(ela: Duration): string =
   aristo_profile.toStr(ela)
@@ -179,12 +169,12 @@ func toStr*(ela: Duration): string =
 # Public new API logging framework
 # ------------------------------------------------------------------------------
 
-template beginNewApi*(w: CoreDxApiTrackRef; s: static[CoreDbFnInx]) =
+template beginNewApi*(w: CoreDbApiTrackRef; s: static[CoreDbFnInx]) =
   when CoreDbEnableApiProfiling:
     const bnaCtx {.inject.} = s       # Local use only
   let bnaStart {.inject.} = getTime() # Local use only
 
-template endNewApiIf*(w: CoreDxApiTrackRef; code: untyped) =
+template endNewApiIf*(w: CoreDbApiTrackRef; code: untyped) =
   block:
     when typeof(w) is CoreDbRef:
       let db = w
diff --git a/nimbus/db/core_db/base/base_desc.nim b/nimbus/db/core_db/base/base_desc.nim
index a6c872435..4517fb626 100644
--- a/nimbus/db/core_db/base/base_desc.nim
+++ b/nimbus/db/core_db/base/base_desc.nim
@@ -97,15 +97,15 @@ type
   CoreDbBaseColPrintFn* = proc(vid: CoreDbColRef): string {.noRaise.}
   CoreDbBaseErrorPrintFn* = proc(e: CoreDbErrorRef): string {.noRaise.}
   CoreDbBaseLevelFn* = proc(): int {.noRaise.}
-  CoreDbBaseNewKvtFn* = proc(): CoreDbRc[CoreDxKvtRef] {.noRaise.}
+  CoreDbBaseNewKvtFn* = proc(): CoreDbRc[CoreDbKvtRef] {.noRaise.}
   CoreDbBaseNewCtxFn* = proc(): CoreDbCtxRef {.noRaise.}
   CoreDbBaseNewCtxFromTxFn* = proc(
     colState: Hash256; kind: CoreDbColType): CoreDbRc[CoreDbCtxRef] {.noRaise.}
   CoreDbBaseSwapCtxFn* = proc(ctx: CoreDbCtxRef): CoreDbCtxRef {.noRaise.}
-  CoreDbBaseTxBeginFn* = proc(): CoreDxTxRef {.noRaise.}
+  CoreDbBaseTxBeginFn* = proc(): CoreDbTxRef {.noRaise.}
   CoreDbBaseNewCaptFn* =
-    proc(flgs: set[CoreDbCaptFlags]): CoreDbRc[CoreDxCaptRef] {.noRaise.}
-  CoreDbBaseGetCaptFn* = proc(): CoreDbRc[CoreDxCaptRef] {.noRaise.}
+    proc(flgs: set[CoreDbCaptFlags]): CoreDbRc[CoreDbCaptRef] {.noRaise.}
+  CoreDbBaseGetCaptFn* = proc(): CoreDbRc[CoreDbCaptRef] {.noRaise.}
   CoreDbBasePersistentFn* =
     proc(bn: Opt[BlockNumber]): CoreDbRc[void] {.noRaise.}
 
@@ -164,9 +164,9 @@ type
     colType: CoreDbColType; colState: Hash256; address: Opt[EthAddress];
     ): CoreDbRc[CoreDbColRef] {.noRaise.}
   CoreDbCtxGetMptFn* = proc(
-    root: CoreDbColRef): CoreDbRc[CoreDxMptRef] {.noRaise.}
+    root: CoreDbColRef): CoreDbRc[CoreDbMptRef] {.noRaise.}
   CoreDbCtxGetAccFn* = proc(
-    root: CoreDbColRef): CoreDbRc[CoreDxAccRef] {.noRaise.}
+    root: CoreDbColRef): CoreDbRc[CoreDbAccRef] {.noRaise.}
   CoreDbCtxForgetFn* = proc() {.noRaise.}
 
   CoreDbCtxFns* = object
@@ -207,7 +207,7 @@ type
   # ----------------------------------------------------
   # Sub-descriptor: Mpt/hexary trie methods for accounts
   # ------------------------------------------------------
-  CoreDbAccGetMptFn* = proc(): CoreDbRc[CoreDxMptRef] {.noRaise.}
+  CoreDbAccGetMptFn* = proc(): CoreDbRc[CoreDbMptRef] {.noRaise.}
   CoreDbAccFetchFn* = proc(k: EthAddress): CoreDbRc[CoreDbAccount] {.noRaise.}
   CoreDbAccDeleteFn* = proc(k: EthAddress): CoreDbRc[void] {.noRaise.}
   CoreDbAccStoDeleteFn* = proc(k: EthAddress): CoreDbRc[void] {.noRaise.}
@@ -283,25 +283,24 @@ type
     ## Backend wrapper for direct backend access
     parent*: CoreDbRef
 
-  CoreDxKvtRef* = ref CoreDxKvtObj
-  CoreDxKvtObj* = object of RootObj
+  CoreDbKvtRef* = ref object of RootRef
     ## Statically initialised Key-Value pair table living in `CoreDbRef`
     parent*: CoreDbRef
     methods*: CoreDbKvtFns
 
   CoreDbCtxRef* = ref object of RootRef
-    ## Context for `CoreDxMptRef` and `CoreDxAccRef`
+    ## Context for `CoreDbMptRef` and `CoreDbAccRef`
     parent*: CoreDbRef
     methods*: CoreDbCtxFns
 
-  CoreDxMptRef* = ref object of RootRef
+  CoreDbMptRef* = ref object of RootRef
     ## Hexary/Merkle-Patricia tree derived from `CoreDbRef`, will be
     ## initialised on-the-fly.
     parent*: CoreDbRef
     methods*: CoreDbMptFns
 
-  CoreDxAccRef* = ref object of RootRef
-    ## Similar to `CoreDxKvtRef`, only dealing with `CoreDbAccount` data
+  CoreDbAccRef* = ref object of RootRef
+    ## Similar to `CoreDbKvtRef`, only dealing with `CoreDbAccount` data
     ## rather than `Blob` values.
     parent*: CoreDbRef
     methods*: CoreDbAccFns
@@ -312,19 +311,12 @@ type
     parent*: CoreDbRef
     ready*: bool              ## Must be set `true` to enable
 
-  CoreDxPhkRef* = ref object
-    ## Similar to `CoreDbMptRef` but with pre-hashed keys. That is, any
-    ## argument key for `merge()`, `fetch()` etc. will be hashed first
-    ## before being applied.
-    toMpt*: CoreDxMptRef
-    methods*: CoreDbMptFns
-
-  CoreDxTxRef* = ref object of RootRef
+  CoreDbTxRef* = ref object of RootRef
     ## Transaction descriptor derived from `CoreDbRef`
     parent*: CoreDbRef
     methods*: CoreDbTxFns
 
-  CoreDxCaptRef* = ref object
+  CoreDbCaptRef* = ref object
     ## Db transaction tracer derived from `CoreDbRef`
     parent*: CoreDbRef
     methods*: CoreDbCaptFns
diff --git a/nimbus/db/core_db/base/validate.nim b/nimbus/db/core_db/base/validate.nim
index 0c2bbdc4b..e56d2cb57 100644
--- a/nimbus/db/core_db/base/validate.nim
+++ b/nimbus/db/core_db/base/validate.nim
@@ -16,10 +16,10 @@ type
   EphemMethodsDesc = CoreDbKvtBackendRef | CoreDbMptBackendRef | CoreDbColRef
 
   MethodsDesc =
-    CoreDxKvtRef |
-    CoreDbCtxRef | CoreDxMptRef | CoreDxPhkRef | CoreDxAccRef  |
-    CoreDxTxRef  |
-    CoreDxCaptRef
+    CoreDbKvtRef |
+    CoreDbCtxRef | CoreDbMptRef | CoreDbAccRef  |
+    CoreDbTxRef  |
+    CoreDbCaptRef
 
   ValidateDesc* = MethodsDesc | EphemMethodsDesc | CoreDbErrorRef
 
@@ -88,7 +88,7 @@ proc validateMethodsDesc(eph: EphemMethodsDesc) =
   doAssert not eph.isNil
   doAssert not eph.parent.isNil
 
-proc validateMethodsDesc(kvt: CoreDxKvtRef) =
+proc validateMethodsDesc(kvt: CoreDbKvtRef) =
   doAssert not kvt.isNil
   doAssert not kvt.parent.isNil
   kvt.methods.validateMethodsDesc
@@ -98,30 +98,25 @@ proc validateMethodsDesc(ctx: CoreDbCtxRef) =
   doAssert not ctx.parent.isNil
   ctx.methods.validateMethodsDesc
 
-proc validateMethodsDesc(mpt: CoreDxMptRef) =
+proc validateMethodsDesc(mpt: CoreDbMptRef) =
   doAssert not mpt.isNil
   doAssert not mpt.parent.isNil
   mpt.methods.validateMethodsDesc
 
-proc validateMethodsDesc(acc: CoreDxAccRef) =
+proc validateMethodsDesc(acc: CoreDbAccRef) =
   doAssert not acc.isNil
   doAssert not acc.parent.isNil
   acc.methods.validateMethodsDesc
 
-proc validateMethodsDesc(phk: CoreDxPhkRef) =
-  doAssert not phk.isNil
-  doAssert not phk.toMpt.isNil
-  phk.methods.validateMethodsDesc
-
 when false: # currently disabled
-  proc validateMethodsDesc(cpt: CoreDxCaptRef) =
+  proc validateMethodsDesc(cpt: CoreDbCaptRef) =
     doAssert not cpt.isNil
     doAssert not cpt.parent.isNil
     doAssert not cpt.methods.recorderFn.isNil
     doAssert not cpt.methods.getFlagsFn.isNil
     doAssert not cpt.methods.forgetFn.isNil
 
-proc validateMethodsDesc(tx: CoreDxTxRef) =
+proc validateMethodsDesc(tx: CoreDbTxRef) =
   doAssert not tx.isNil
   doAssert not tx.parent.isNil
   doAssert not tx.methods.levelFn.isNil
diff --git a/nimbus/db/core_db/base_iterators.nim b/nimbus/db/core_db/base_iterators.nim
index 89da113b3..cc7551559 100644
--- a/nimbus/db/core_db/base_iterators.nim
+++ b/nimbus/db/core_db/base_iterators.nim
@@ -31,7 +31,7 @@ when CoreDbEnableApiTracking:
 # Public iterators
 # ------------------------------------------------------------------------------
 
-iterator pairs*(kvt: CoreDxKvtRef): (Blob, Blob) {.apiRaise.} =
+iterator pairs*(kvt: CoreDbKvtRef): (Blob, Blob) {.apiRaise.} =
   ## Iterator supported on memory DB (otherwise implementation dependent)
   ##
   kvt.setTrackNewApi KvtPairsIt
@@ -46,8 +46,8 @@ iterator pairs*(kvt: CoreDxKvtRef): (Blob, Blob) {.apiRaise.} =
     raiseAssert: "Unsupported database type: " & $kvt.parent.dbType
   kvt.ifTrackNewApi: debug newApiTxt, api, elapsed
 
-iterator pairs*(mpt: CoreDxMptRef): (Blob, Blob) =
-  ## Trie traversal, only supported for `CoreDxMptRef` (not `Phk`)
+iterator pairs*(mpt: CoreDbMptRef): (Blob, Blob) =
+  ## Trie traversal, only supported for `CoreDbMptRef`
   ##
   mpt.setTrackNewApi MptPairsIt
   case mpt.parent.dbType:
@@ -60,8 +60,8 @@ iterator pairs*(mpt: CoreDxMptRef): (Blob, Blob) =
     let trie = mpt.methods.getColFn()
     debug newApiTxt, api, elapsed, trie
 
-iterator replicate*(mpt: CoreDxMptRef): (Blob, Blob) {.apiRaise.} =
-  ## Low level trie dump, only supported for `CoreDxMptRef` (not `Phk`)
+iterator replicate*(mpt: CoreDbMptRef): (Blob, Blob) {.apiRaise.} =
+  ## Low level trie dump, only supported for `CoreDbMptRef`
   ##
   mpt.setTrackNewApi MptReplicateIt
   case mpt.parent.dbType:
diff --git a/nimbus/db/core_db/base_iterators_persistent.nim b/nimbus/db/core_db/base_iterators_persistent.nim
index e1c451e06..222fcf0f6 100644
--- a/nimbus/db/core_db/base_iterators_persistent.nim
+++ b/nimbus/db/core_db/base_iterators_persistent.nim
@@ -31,7 +31,7 @@ when CoreDbEnableApiTracking:
 # Public iterators
 # ------------------------------------------------------------------------------
 
-iterator replicatePersistent*(mpt: CoreDxMptRef): (Blob, Blob) {.rlpRaise.} =
+iterator replicatePersistent*(mpt: CoreDbMptRef): (Blob, Blob) {.rlpRaise.} =
   ## Extended version of `replicate()` for `Aristo` persistent backend.
   ##
   mpt.setTrackNewApi MptReplicateIt
diff --git a/nimbus/db/ledger/accounts_ledger.nim b/nimbus/db/ledger/accounts_ledger.nim
index 286aee350..1ddf9abe2 100644
--- a/nimbus/db/ledger/accounts_ledger.nim
+++ b/nimbus/db/ledger/accounts_ledger.nim
@@ -64,7 +64,7 @@ type
 
   AccountsLedgerRef* = ref object
     ledger: AccountLedger
-    kvt: CoreDxKvtRef
+    kvt: CoreDbKvtRef
     savePoint: LedgerSavePoint
     witnessCache: Table[EthAddress, WitnessData]
     isDirty: bool
@@ -412,7 +412,7 @@ proc getNonce*(ac: AccountsLedgerRef, address: EthAddress): AccountNonce =
   if acc.isNil: emptyEthAccount.nonce
   else: acc.statement.nonce
 
-proc getCode(acc: AccountRef, kvt: CoreDxKvtRef): lent seq[byte] =
+proc getCode(acc: AccountRef, kvt: CoreDbKvtRef): lent seq[byte] =
   if CodeLoaded notin acc.flags and CodeChanged notin acc.flags:
     if acc.statement.codeHash != EMPTY_CODE_HASH:
       var rc = kvt.get(contractHashKey(acc.statement.codeHash).toOpenArray)
diff --git a/nimbus/db/ledger/base.nim b/nimbus/db/ledger/base.nim
index 78902c109..50d896082 100644
--- a/nimbus/db/ledger/base.nim
+++ b/nimbus/db/ledger/base.nim
@@ -351,9 +351,9 @@ proc getAccessList*(ldg: LedgerRef): AccessList =
 proc rootHash*(ldg: LedgerRef): KeccakHash =
   ldg.state()
 
-proc getMpt*(ldg: LedgerRef): CoreDxMptRef =
+proc getMpt*(ldg: LedgerRef): CoreDbMptRef =
   ldg.beginTrackApi LdgGetMptFn
-  result = ldg.ac.rawTrie.CoreDxAccRef.getMpt
+  result = ldg.ac.rawTrie.CoreDbAccRef.getMpt
   ldg.ifTrackApi: debug apiTxt, api, elapsed, result
 
 proc getEthAccount*(ldg: LedgerRef, eAddr: EthAddress): Account =
diff --git a/nimbus/db/ledger/base/api_tracking.nim b/nimbus/db/ledger/base/api_tracking.nim
index 1342e7de0..624c9c627 100644
--- a/nimbus/db/ledger/base/api_tracking.nim
+++ b/nimbus/db/ledger/base/api_tracking.nim
@@ -100,7 +100,7 @@ func toStr*(w: Hash256): string =
 
 when declared(CoreDbMptRef):
   func toStr*(w: CoreDbMptRef): string =
-    if w.CoreDxMptRef.isNil: "MptRef(nil)" else: "MptRef"
+    if w.CoreDbMptRef.isNil: "MptRef(nil)" else: "MptRef"
 
 func toStr*(w: Blob): string =
   if 0 < w.len and w.len < 5: "<" & w.oaToStr & ">"
diff --git a/nimbus/db/ledger/distinct_ledgers.nim b/nimbus/db/ledger/distinct_ledgers.nim
index 4294f7d23..2f92b2e5b 100644
--- a/nimbus/db/ledger/distinct_ledgers.nim
+++ b/nimbus/db/ledger/distinct_ledgers.nim
@@ -32,8 +32,8 @@ import
   ".."/[core_db, storage_types]
 
 type
-  AccountLedger* = distinct CoreDxAccRef
-  StorageLedger* = distinct CoreDxPhkRef
+  AccountLedger* = distinct CoreDbAccRef
+  StorageLedger* = distinct CoreDbMptRef
   SomeLedger* = AccountLedger | StorageLedger
 
 const
@@ -56,7 +56,7 @@ proc toSvp*(sl: StorageLedger): seq[(UInt256,UInt256)] =
   let kvt = db.newKvt
   var kvp: Table[UInt256,UInt256]
   try:
-    for (slotHash,val) in sl.distinctBase.toMpt.pairs:
+    for (slotHash,val) in sl.distinctBase.pairs:
       let rc = kvt.get(slotHashToSlotKey(slotHash).toOpenArray)
       if rc.isErr:
         warn "StorageLedger.dump()", slotHash, error=($$rc.error)
@@ -186,22 +186,22 @@ proc init*(
       if rc.isErr:
         raiseAssert info & $$rc.error
       rc.value
-  mpt.toPhk.T
+  mpt.T
 
 proc fetch*(sl: StorageLedger, slot: UInt256): Result[Blob,void] =
-  var rc = sl.distinctBase.fetch(slot.toBytesBE)
+  var rc = sl.distinctBase.fetch(slot.toBytesBE.keccakHash.data)
   if rc.isErr:
     return err()
   ok move(rc.value)
 
 proc merge*(sl: StorageLedger, slot: UInt256, value: openArray[byte]) =
   const info = "StorageLedger/merge(): "
-  sl.distinctBase.merge(slot.toBytesBE, value).isOkOr:
+  sl.distinctBase.merge(slot.toBytesBE.keccakHash.data, value).isOkOr:
     raiseAssert info & $$error
 
 proc delete*(sl: StorageLedger, slot: UInt256) =
   const info = "StorageLedger/delete(): "
-  sl.distinctBase.delete(slot.toBytesBE).isOkOr:
+  sl.distinctBase.delete(slot.toBytesBE.keccakHash.data).isOkOr:
     if error.error == MptNotFound:
       return
     raiseAssert info & $$error
diff --git a/nimbus/db/trie_get_branch.nim b/nimbus/db/trie_get_branch.nim
index b3786ea6d..962b772b2 100644
--- a/nimbus/db/trie_get_branch.nim
+++ b/nimbus/db/trie_get_branch.nim
@@ -8,8 +8,8 @@
 # at your option. This file may not be copied, modified, or distributed except
 # according to those terms.
 
-# This implementation of getBranch on the CoreDbPhkRef type is a temporary solution
-# which can be removed once we get an equivient proc defined on the CoreDbPhkRef type
+# This implementation of getBranch on the CoreDbMptRef type is a temporary solution
+# which can be removed once we get an equivient proc defined on the CoreDbMptRef type
 # in the db layer.
 
 {.push raises: [].}
@@ -88,7 +88,12 @@ proc getBranchAux(
     raise newException(RlpError, "node has an unexpected number of children")
 
 proc getBranch*(
-    self: CoreDxPhkRef;
+    # self: CoreDxPhkRef;
+    # Note that PHK type has been removed. The difference PHK an MPT was that
+    # the keys of the PHK were pre-hased (as in the legacy `SecureHexaryTrie`
+    # object.) Can this code have worked at all? Looking at the `keyHash`
+    # below it would mean the `key` was double hashed? -- j
+    self: CoreDbMptRef;
     key: openArray[byte]): seq[seq[byte]] {.raises: [RlpError].} =
   let
     keyHash = keccakHash(key).data
diff --git a/nimbus/no-tracer.nim b/nimbus/no-tracer.nim
index 00c3a9d13..aff63138c 100644
--- a/nimbus/no-tracer.nim
+++ b/nimbus/no-tracer.nim
@@ -104,7 +104,7 @@ proc dumpMemoryDB*(node: JsonNode, kvt: TableRef[common.Blob, common.Blob]) =
     n[k.toHex(false)] = %v
   node["state"] = n
 
-proc dumpMemoryDB*(node: JsonNode, capture: CoreDxCaptRef) =
+proc dumpMemoryDB*(node: JsonNode, capture: CoreDbCaptRef) =
   node.dumpMemoryDB capture.logDb
 
 const
diff --git a/premix/persist.nim b/premix/persist.nim
index 2bd597fe7..022f6bd40 100644
--- a/premix/persist.nim
+++ b/premix/persist.nim
@@ -40,7 +40,7 @@ else:
 template persistToDb(db: CoreDbRef, body: untyped) =
   block: body
 
-proc contains(kvt: CoreDxKvtRef; key: openArray[byte]): bool =
+proc contains(kvt: CoreDbKvtRef; key: openArray[byte]): bool =
   kvt.hasKey(key).expect "valid bool"
 
 proc main() {.used.} =