diff --git a/nimbus/compile_info.nim b/nimbus/compile_info.nim
index 14a0e6c57..d740925c6 100644
--- a/nimbus/compile_info.nim
+++ b/nimbus/compile_info.nim
@@ -8,6 +8,10 @@
 # at your option. This file may not be copied, modified, or distributed except
 # according to those terms.
 
+import
+  ./db/core_db/base/base_config,
+  ./db/ledger/base/base_config
+
 func vmName(): string =
   when defined(evmc_enabled):
     "evmc"
@@ -23,6 +27,10 @@ const
       rc &= ", chunked-rlpx"
     when defined(boehmgc):
       rc &= ", boehm/gc"
+    when 0 < coreDbBaseConfigExtras.len:
+       rc &= ", " & coreDbBaseConfigExtras
+    when 0 < ledgerBaseConfigExtras.len:
+       rc &= ", " & ledgerBaseConfigExtras
     rc &= " enabled"
     rc
 
diff --git a/nimbus/db/aristo/aristo_api.nim b/nimbus/db/aristo/aristo_api.nim
index be1f1208b..135051b0d 100644
--- a/nimbus/db/aristo/aristo_api.nim
+++ b/nimbus/db/aristo/aristo_api.nim
@@ -851,9 +851,9 @@ func init*(
         result = api.pathAsBlob(a)
 
   profApi.persist =
-    proc(a: AristoDbRef; b = 0u64; c = false): auto =
+    proc(a: AristoDbRef; b = 0u64): auto =
        AristoApiProfPersistFn.profileRunner:
-        result = api.persist(a, b, c)
+        result = api.persist(a, b)
 
   profApi.reCentre =
     proc(a: AristoDbRef): auto =
diff --git a/nimbus/db/aristo/aristo_desc/desc_structural.nim b/nimbus/db/aristo/aristo_desc/desc_structural.nim
index 7e3fef54b..49648ad89 100644
--- a/nimbus/db/aristo/aristo_desc/desc_structural.nim
+++ b/nimbus/db/aristo/aristo_desc/desc_structural.nim
@@ -18,7 +18,7 @@ import
   std/[hashes, tables],
   stint,
   eth/common,
-  "."/[desc_error, desc_identifiers]
+  ./desc_identifiers
 
 export stint
 
@@ -74,7 +74,6 @@ type
   NodeRef* = ref object of VertexRef
     ## Combined record for a *traditional* ``Merkle Patricia Tree` node merged
     ## with a structural `VertexRef` type object.
-    error*: AristoError              ## Used for error signalling in RLP decoder
     key*: array[16,HashKey]          ## Merkle hash/es for vertices
 
   # ----------------------
diff --git a/nimbus/db/aristo/aristo_fetch.nim b/nimbus/db/aristo/aristo_fetch.nim
index 9f1b6db10..4fc8403eb 100644
--- a/nimbus/db/aristo/aristo_fetch.nim
+++ b/nimbus/db/aristo/aristo_fetch.nim
@@ -129,7 +129,7 @@ proc hasAccountPayload(
 
 proc fetchAccountHike*(
     db: AristoDbRef;                   # Database
-    accPath: Hash256;          # Implies a storage ID (if any)
+    accPath: Hash256;                  # Implies a storage ID (if any)
       ): Result[Hike,AristoError] =
   ## Verify that the `accPath` argument properly referres to a storage root
   ## vertex ID. The function will reset the keys along the `accPath` for
diff --git a/nimbus/db/core_db/base.nim b/nimbus/db/core_db/base.nim
index 4e00a5c5f..7da24100b 100644
--- a/nimbus/db/core_db/base.nim
+++ b/nimbus/db/core_db/base.nim
@@ -15,14 +15,13 @@ import
   eth/common,
   "../.."/[constants, errors],
   ".."/[kvt, aristo],
+  ./backend/aristo_db,
   ./base/[api_tracking, base_config, base_desc, base_helpers]
 
 export
   CoreDbAccRef,
   CoreDbAccount,
   CoreDbApiError,
-  #CoreDbCaptFlags,
-  #CoreDbCaptRef,
   CoreDbCtxRef,
   CoreDbErrorCode,
   CoreDbError,
@@ -34,7 +33,6 @@ export
   CoreDbType
 
 when CoreDbEnableApiTracking:
-  {.warning: "*** Provided API logging for CoreDB (disabled by default)".}
   import
     chronicles
   logScope:
@@ -42,16 +40,18 @@ when CoreDbEnableApiTracking:
   const
     logTxt = "API"
 
-
 when CoreDbEnableProfiling:
-  {.warning: "*** Enabled profiling for CoreDB (also tracer API available)".}
   export
     CoreDbFnInx,
     CoreDbProfListRef
 
-
-when CoreDbEnableApiJumpTable:
-  discard
+when CoreDbEnableCaptJournal and false:
+  import
+    ./backend/aristo_trace
+  type
+    CoreDbCaptRef* = distinct TraceLogInstRef
+  func `$`(p: CoreDbCaptRef): string =
+    if p.distinctBase.isNil: "<nil>" else: "<capt>"
 else:
   import
     ../aristo/[
@@ -714,7 +714,7 @@ proc dispose*(tx: CoreDbTxRef) =
 # Public tracer methods
 # ------------------------------------------------------------------------------
 
-when false: # currently disabled
+when CoreDbEnableCaptJournal and false: # currently disabled
   proc newCapture*(
       db: CoreDbRef;
         ): CoreDbRc[CoreDbCaptRef] =
diff --git a/nimbus/db/core_db/base/base_config.nim b/nimbus/db/core_db/base/base_config.nim
index 7b27a750f..d5936738b 100644
--- a/nimbus/db/core_db/base/base_config.nim
+++ b/nimbus/db/core_db/base/base_config.nim
@@ -20,38 +20,78 @@ const
     ## Tracking noise is then enabled by setting the flag `trackCoreDbApi` to
     ## `true` in the `CoreDbRef` descriptor.
 
-  EnableProfiling = false
-    ## Enables profiling of the backend. If the flag `EnableApiTracking` is
-    ## also set the API will also be subject to profiling.
+  AutoValidateDescriptors = defined(release).not or
+                            defined(unittest2DisableParamFiltering)
+    ## No validatinon needed for production suite.
+    ##
+    ## The `unittest2DisableParamFiltering` flag is coincidentally used by
+    ## unit/integration tests which makes it convenient to piggyback on that
+    ## for enabling debugging checks.
 
-  EnableCaptJournal = defined(release).not
-    ## Enables the tracer facility. If set `true` capture journal directives
-    ## like `newCapture()` will be available.
-  
-  NoisyCaptJournal = true
-    ## Provide extra logging with the tracer facility if available.
-  
-  EnableApiJumpTable = false
+  EnableApiJumpTable = defined(dbjapi_enabled) or
+                       defined(unittest2DisableParamFiltering)
     ## This flag enables the functions jump table even if `EnableApiProfiling`
     ## and `EnableCaptJournal` is set `false` in realease mode. This setting
     ## should be used for debugging, only.
+    ##
+    ## The `unittest2DisableParamFiltering` flag is coincidentally used by
+    ## unit/integration tests which makes it convenient to piggyback on that
+    ## for providing API jump tables.
+
+  EnableProfiling = false
+    ## Enables profiling of the backend if the flags ` EnableApiJumpTable`
+    ## and `EnableApiTracking` are also set. Profiling will then be enabled
+    ## with the flag `trackCoreDbApi` (which also enables extra logging.)
+
+  EnableCaptJournal = true
+    ## Enables the tracer facility if the flag ` EnableApiJumpTable` is
+    ## also set. In that case the capture journal directives like
+    ## `newCapture()` will be available.
+
+  NoisyCaptJournal = true
+    ## Provide extra logging with the tracer facility if available.
 
-  AutoValidateDescriptors = defined(release).not
-    ## No validatinon needed for production suite.
 
 # Exportable constants (leave alone this section)
 const
   CoreDbEnableApiTracking* = EnableApiTracking
 
-  CoreDbEnableProfiling* = EnableProfiling
-
-  CoreDbEnableCaptJournal* = EnableCaptJournal
-
-  CoreDbNoisyCaptJournal* = CoreDbEnableCaptJournal and NoisyCaptJournal
-
-  CoreDbEnableApiJumpTable* =
-    CoreDbEnableProfiling or CoreDbEnableCaptJournal or EnableApiJumpTable
-
   CoreDbAutoValidateDescriptors* = AutoValidateDescriptors
 
+  # Api jump table dependent settings:
+
+  CoreDbEnableApiJumpTable* = EnableApiJumpTable
+
+  CoreDbEnableProfiling* = EnableProfiling and CoreDbEnableApiJumpTable
+
+  CoreDbEnableCaptJournal* = EnableCaptJournal and CoreDbEnableApiJumpTable
+
+  CoreDbNoisyCaptJournal* = NoisyCaptJournal and CoreDbEnableCaptJournal
+
+
+# Support warning about extra compile time options. For production, non of
+# the above features should be enabled.
+import strutils
+const coreDbBaseConfigExtras* = block:
+  var s: seq[string]
+  when CoreDbEnableApiTracking:
+    s.add "logging"
+  when CoreDbAutoValidateDescriptors:
+    s.add "validate"
+  when CoreDbEnableProfiling:
+    s.add "profiling"
+  when CoreDbEnableCaptJournal:
+    when CoreDbNoisyCaptJournal:
+      s.add "noisy tracer"
+    else:
+      s.add "tracer"
+  when CoreDbEnableApiJumpTable and
+       not CoreDbEnableProfiling and
+       not CoreDbEnableCaptJournal:
+    s.add "Api jump table"
+  if s.len == 0:
+    ""
+  else:
+    "CoreDb(" & s.join(", ") & ")"
+
 # End
diff --git a/nimbus/db/ledger/base.nim b/nimbus/db/ledger/base.nim
index 44ea2b85a..ed7298c4b 100644
--- a/nimbus/db/ledger/base.nim
+++ b/nimbus/db/ledger/base.nim
@@ -33,7 +33,6 @@ export
 # ------------------------------------------------------------------------------
 
 when LedgerEnableApiTracking:
-  {.warning: "*** Provided API logging for Ledger (disabled by default)".}
   import
     std/times,
     chronicles
@@ -43,7 +42,6 @@ when LedgerEnableApiTracking:
     apiTxt = "API"
 
 when LedgerEnableApiProfiling:
-  {.warning: "*** Provided API profiling for Ledger (disabled by default)".}
   export
     LedgerFnInx,
     LedgerProfListRef
diff --git a/nimbus/db/ledger/base/base_config.nim b/nimbus/db/ledger/base/base_config.nim
index f9aeb086e..07ba08d0d 100644
--- a/nimbus/db/ledger/base/base_config.nim
+++ b/nimbus/db/ledger/base/base_config.nim
@@ -30,4 +30,19 @@ const
   LedgerEnableApiTracking* = EnableApiTracking and CoreDbEnableApiTracking
   LedgerEnableApiProfiling* = EnableApiProfiling and CoreDbEnableApiJumpTable
 
+
+# Support warning about extra compile time options. For production, non of
+# the above features should be enabled.
+import strutils
+const ledgerBaseConfigExtras* = block:
+  var s: seq[string]
+  when LedgerEnableApiTracking:
+    s.add "logging"
+  when LedgerEnableApiProfiling:
+    s.add "profiling"
+  if s.len == 0:
+    ""
+  else:
+    "Ledger(" & s.join(", ") & ")"
+
 # End
diff --git a/nimbus/db/ledger/base/base_helpers.nim b/nimbus/db/ledger/base/base_helpers.nim
index ad77ee8c0..7ae7d09d0 100644
--- a/nimbus/db/ledger/base/base_helpers.nim
+++ b/nimbus/db/ledger/base/base_helpers.nim
@@ -17,6 +17,8 @@ import
 # ------------------------------------------------------------------------------
 
 when LedgerEnableApiProfiling:
+  import api_tracking
+
   proc ldgProfData*(db: CoreDbRef): LedgerProfListRef =
     ## Return profiling data table (only available in profiling mode). If
     ## available (i.e. non-nil), result data can be organised by the functions