diff --git a/bin/miaou-bash b/bin/miaou-bash
index b6ae4d3..cc574e3 100755
--- a/bin/miaou-bash
+++ b/bin/miaou-bash
@@ -571,9 +571,13 @@ function on_exit {
   if ! is_true $CHILD_PROCESS; then
     2>&3 >&3 dump_stderr
     if [[ -v failure_type && $failure_code -gt 0 ]]; then
-      2>&3 >&4 dump_failure
-      if [[ -v error_source ]]; then
-        2>&3 >&4 dump_stacktrace
+      if [[ $failure_type == 'UNKNOWN ERROR' && $failure_payload == "source \"\$SCRIPT\"" ]]; then
+        miaou_debug "<unknown_error bypass=true cause=source_script/>"
+      else
+        2>&3 >&4 dump_failure
+        if [[ -v error_source ]]; then
+          2>&3 >&4 dump_stacktrace
+        fi
       fi
     fi
   elif [[ -v failure_type ]]; then
diff --git a/doc/bash_tips.md b/doc/bash_tips.md
index 9aae9ea..6a1f84f 100644
--- a/doc/bash_tips.md
+++ b/doc/bash_tips.md
@@ -35,4 +35,29 @@ count=0
 ```bash
 count=0
 count=$((count+1))
-`
+```
+
+## properly grab $?
+
+> prefer plain `command` rather than `! command`
+> otherwise you will miss out the exit code
+
+### wrong if
+
+```bash
+  if ! command; then
+    local code=$?
+    >&2 echo $code # => 0
+  fi
+```
+
+### right if
+
+```bash
+  if command; then
+    : # useful for preserving $?
+  else
+    local code=$?
+    >&2 echo $code
+  fi
+```
diff --git a/doc/index.md b/doc/index.md
index 5d0ab1b..d4ac7cd 100644
--- a/doc/index.md
+++ b/doc/index.md
@@ -32,6 +32,9 @@ echo 'echo PIPE2' | miaou-bash
 
 ## TODO
 
-* [ ] prompt git shows version with `+` when there is more than one commit over current version. ie: v0.0.0 + 2 commits more should display v-1.0.0+
-* [ ] semver_git_tag should append `RELEASE_NOTES.md` from this TODO markdown file, providing that NEW NOTE section below contains appropriate items to fulfill the current release note
-  * [ ] git log <LATEST_TAG>..HEAD --oneline
+* [ ] prompt should show up version with `+` when there is more than one commit,
+      not yet versioned. ie: v0.0.0 + 2 commits more should display v0.0.0+
+* [ ] semver_git_tag should append `RELEASE_NOTES.md` from this TODO markdown file,
+      providing that NEW NOTE section below contains appropriate items
+      to fulfill the current release note
+* [ ] git log <LATEST_TAG>..HEAD --oneline
diff --git a/test/miaou-bash.test.bash b/test/miaou-bash.test.bash
index 23ac96b..98fc732 100755
--- a/test/miaou-bash.test.bash
+++ b/test/miaou-bash.test.bash
@@ -172,7 +172,9 @@ time {
 
   fail_stderr_count unbound_variable 1
   fail_stderr_count child_error 4
+
   fail_miaou_count command_error_multiline 7
+  fail_miaou_count unknown 1
 
   fail_stderr_grep two_options 'ERROR: too many args 2, either single option or SCRIPT + args accepted!'
   fail_stderr_grep script_not_found "ERROR: script 'doesnt_exist' not found!"
diff --git a/test/stub/scenario.bash b/test/stub/scenario.bash
index 7227c24..1d9ded3 100755
--- a/test/stub/scenario.bash
+++ b/test/stub/scenario.bash
@@ -12,6 +12,15 @@ function do_subshell_false {
   result=$(false)
 }
 
+function do_unknown {
+  source /dev/stdin <<EOF
+echo START
+>&2 echo weird
+builtin exit 2
+echo END
+EOF
+}
+
 function do_heredoc {
   # miaou-bash <<EOF
   source /dev/stdin <<EOF