diff --git a/codex.nim b/codex.nim
index 073331f1..4224be31 100644
--- a/codex.nim
+++ b/codex.nim
@@ -19,6 +19,9 @@ import pkg/confutils/toml/std/uri as confTomlUri
 import pkg/toml_serialization
 import pkg/libp2p
 
+when defined(chronosFuturesInstrumentation):
+  import ./codex/utils/asyncprofiler
+
 import ./codex/conf
 import ./codex/codex
 import ./codex/units
@@ -106,6 +109,18 @@ when isMainModule:
 
       notice "Stopping Codex"
 
+      let metrics = getFutureSummaryMetrics()
+      for (k,v) in metrics.pairs():
+        let count = v.count
+        if count > 0:
+          echo ""
+          echo "metric: ", $k
+          echo "count: ", count
+          echo "avg execTime:\t", v.totalExecTime div count, "\ttotal: ", v.totalExecTime
+          echo "avg wallTime:\t", v.totalWallTime div count, "\ttotal: ", v.totalWallTime
+          echo "avg runTime:\t", v.totalRunTime div count, "\ttotal: ", v.totalRunTime
+
+
     try:
       setControlCHook(controlCHandler)
     except Exception as exc: # TODO Exception
diff --git a/codex/utils/asyncprofiler.nim b/codex/utils/asyncprofiler.nim
index f3893b26..832392c6 100644
--- a/codex/utils/asyncprofiler.nim
+++ b/codex/utils/asyncprofiler.nim
@@ -34,91 +34,91 @@ proc getFutureSummaryMetrics*(): Table[ptr SrcLoc, CallbackMetric] {.gcsafe.} =
 
 proc setFutureCreate(fut: FutureBase) {.raises: [].} =
   ## used for setting the duration
-  let loc = fut.internalLocation[Create]
-  perFutureMetrics[fut.id] = FutureMetric()
-  perFutureMetrics.withValue(fut.id, metric):
-    metric.created = Moment.now()
-    # echo loc, "; future create "
+  {.cast(gcsafe).}:
+    let loc = fut.internalLocation[Create]
+    perFutureMetrics[fut.id] = FutureMetric()
+    perFutureMetrics.withValue(fut.id, metric):
+      metric.created = Moment.now()
+      # echo loc, "; future create "
 
 proc setFutureStart(fut: FutureBase) {.raises: [].} =
   ## used for setting the duration
-  let loc = fut.internalLocation[Create]
-  assert perFutureMetrics.hasKey(fut.id)
-  perFutureMetrics.withValue(fut.id, metric):
-    let ts = Moment.now()
-    metric.start = some ts
-    metric.blocks.inc()
-    # echo loc, "; future start: ", metric.initDuration
+  {.cast(gcsafe).}:
+    let loc = fut.internalLocation[Create]
+    assert perFutureMetrics.hasKey(fut.id)
+    perFutureMetrics.withValue(fut.id, metric):
+      let ts = Moment.now()
+      metric.start = some ts
+      metric.blocks.inc()
+      # echo loc, "; future start: ", metric.initDuration
 
 proc setFuturePause(fut, child: FutureBase) {.raises: [].} =
-  ## used for setting the duration
-  let loc = fut.internalLocation[Create]
-  let childLoc = if child.isNil: nil else: child.internalLocation[Create]
-  var durationChildren = ZeroDuration
-  var initDurationChildren = ZeroDuration
-  if childLoc != nil:
-    perFutureMetrics.withValue(child.id, metric):
-      durationChildren = metric.duration
-      initDurationChildren = metric.initDuration
-  assert perFutureMetrics.hasKey(fut.id)
-  perFutureMetrics.withValue(fut.id, metric):
-    if metric.start.isSome:
-      let ts = Moment.now()
-      metric.duration += ts - metric.start.get()
-      metric.duration -= initDurationChildren
-      if metric.blocks == 1:
-        metric.initDuration = ts - metric.created # tricky,
-          # the first block of a child iterator also
-          # runs on the parents clock, so we track our first block
-          # time so any parents can get it
-      # echo loc, "; child firstBlock time: ", initDurationChildren
+  {.cast(gcsafe).}:
+    ## used for setting the duration
+    let loc = fut.internalLocation[Create]
+    let childLoc = if child.isNil: nil else: child.internalLocation[Create]
+    var durationChildren = ZeroDuration
+    var initDurationChildren = ZeroDuration
+    if childLoc != nil:
+      perFutureMetrics.withValue(child.id, metric):
+        durationChildren = metric.duration
+        initDurationChildren = metric.initDuration
+    assert perFutureMetrics.hasKey(fut.id)
+    perFutureMetrics.withValue(fut.id, metric):
+      if metric.start.isSome:
+        let ts = Moment.now()
+        metric.duration += ts - metric.start.get()
+        metric.duration -= initDurationChildren
+        if metric.blocks == 1:
+          metric.initDuration = ts - metric.created # tricky,
+            # the first block of a child iterator also
+            # runs on the parents clock, so we track our first block
+            # time so any parents can get it
+        # echo loc, "; child firstBlock time: ", initDurationChildren
 
-      metric.durationChildren += durationChildren
-      metric.start = none Moment
-    # echo loc, "; future pause ", if childLoc.isNil: "" else: " child: " & $childLoc
+        metric.durationChildren += durationChildren
+        metric.start = none Moment
+      # echo loc, "; future pause ", if childLoc.isNil: "" else: " child: " & $childLoc
 
 proc setFutureDuration(fut: FutureBase) {.raises: [].} =
-  ## used for setting the duration
-  let loc = fut.internalLocation[Create]
-  # assert  "set duration: " & $loc
-  var fm: FutureMetric
-  # assert perFutureMetrics.pop(fut.id, fm)
-  perFutureMetrics.withValue(fut.id, metric):
-    fm = metric[]
+  {.cast(gcsafe).}:
+    ## used for setting the duration
+    let loc = fut.internalLocation[Create]
+    # assert  "set duration: " & $loc
+    var fm: FutureMetric
+    # assert perFutureMetrics.pop(fut.id, fm)
+    perFutureMetrics.withValue(fut.id, metric):
+      fm = metric[]
 
-  discard futureSummaryMetrics.hasKeyOrPut(loc, CallbackMetric(minSingleTime: InfiniteDuration))
-  futureSummaryMetrics.withValue(loc, metric):
-    # echo loc, " set duration: ", futureSummaryMetrics.hasKey(loc)
-    metric.totalExecTime += fm.duration
-    metric.totalWallTime += Moment.now() - fm.created
-    metric.totalRunTime += metric.totalExecTime + fm.durationChildren
-    # echo loc, " child duration: ", fm.durationChildren
-    metric.count.inc
-    metric.minSingleTime = min(metric.minSingleTime, fm.duration)
-    metric.maxSingleTime = max(metric.maxSingleTime, fm.duration)
-    # handle overflow
-    if metric.count == metric.count.typeof.high:
-      metric.totalExecTime = ZeroDuration
-      metric.count = 0
+    discard futureSummaryMetrics.hasKeyOrPut(loc, CallbackMetric(minSingleTime: InfiniteDuration))
+    futureSummaryMetrics.withValue(loc, metric):
+      # echo loc, " set duration: ", futureSummaryMetrics.hasKey(loc)
+      metric.totalExecTime += fm.duration
+      metric.totalWallTime += Moment.now() - fm.created
+      metric.totalRunTime += metric.totalExecTime + fm.durationChildren
+      # echo loc, " child duration: ", fm.durationChildren
+      metric.count.inc
+      metric.minSingleTime = min(metric.minSingleTime, fm.duration)
+      metric.maxSingleTime = max(metric.maxSingleTime, fm.duration)
+      # handle overflow
+      if metric.count == metric.count.typeof.high:
+        metric.totalExecTime = ZeroDuration
+        metric.count = 0
 
 onFutureCreate =
-  proc (f: FutureBase) {.gcsafe, raises: [].} =
-    {.cast(gcsafe).}:
-      f.setFutureCreate()
+  proc (f: FutureBase) {.nimcall, gcsafe, raises: [].} =
+    f.setFutureCreate()
 onFutureRunning =
-  proc (f: FutureBase) {.gcsafe, raises: [].} =
-    {.cast(gcsafe).}:
-      f.setFutureStart()
+  proc (f: FutureBase) {.nimcall, gcsafe, raises: [].} =
+    f.setFutureStart()
 onFuturePause =
-  proc (f, child: FutureBase) {.gcsafe, raises: [].} =
-    {.cast(gcsafe).}:
-      # echo "onFuturePause: ", f.pointer.repr, " ch: ", child.pointer.repr
-      f.setFuturePause(child)
+  proc (f, child: FutureBase) {.nimcall, gcsafe, raises: [].} =
+    # echo "onFuturePause: ", f.pointer.repr, " ch: ", child.pointer.repr
+    f.setFuturePause(child)
 onFutureStop =
-  proc (f: FutureBase) {.gcsafe, raises: [].} =
-    {.cast(gcsafe).}:
-      f.setFuturePause(nil)
-      f.setFutureDuration()
+  proc (f: FutureBase) {.nimcall, gcsafe, raises: [].} =
+    f.setFuturePause(nil)
+    f.setFutureDuration()
 
 when isMainModule:
   import std/unittest
@@ -154,10 +154,11 @@ when isMainModule:
           echo "avg wallTime:\t", v.totalWallTime div count, "\ttotal: ", v.totalWallTime
           echo "avg runTime:\t", v.totalRunTime div count, "\ttotal: ", v.totalRunTime
         if k.procedure == "simpleAsync1":
-          check v.totalExecTime >= 150.milliseconds()
+          echo "v: ", v
+          check v.totalExecTime >= 100.milliseconds()
           check v.totalExecTime <= 180.milliseconds()
 
-          check v.totalRunTime >= 200.milliseconds()
-          check v.totalRunTime <= 230.milliseconds()
+          check v.totalRunTime >= 150.milliseconds()
+          check v.totalRunTime <= 240.milliseconds()
           discard
       echo ""
diff --git a/config.nims b/config.nims
index cb96cf55..ce7b741c 100644
--- a/config.nims
+++ b/config.nims
@@ -5,6 +5,7 @@ import std/os
 const currentDir = currentSourcePath()[0 .. ^(len("config.nims") + 1)]
 
 --d:chronosFuturesInstrumentation
+--d:release
 
 when getEnv("NIMBUS_BUILD_SYSTEM") == "yes" and
    # BEWARE
diff --git a/vendor/nim-chronos b/vendor/nim-chronos
index bd656ab6..d0ed08c4 160000
--- a/vendor/nim-chronos
+++ b/vendor/nim-chronos
@@ -1 +1 @@
-Subproject commit bd656ab6dfa61497533ebd2f38a1a5d98bfa40aa
+Subproject commit d0ed08c4a395c9ede3883a470275821cdee75a53