diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index e34cf52a4..eeabed821 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -56,7 +56,7 @@ jobs:
           # We're going to check BOLT quotes, so get the latest version
           git clone https://github.com/lightning/bolts.git ../${BOLTDIR}
       - name: Configure
-        run: ./configure
+        run: ./configure --enable-debugbuild
       - name: Check source
         run: make -j 4 check-source BASE_REF="origin/${{ github.base_ref }}"
       - name: Check Generated Files have been updated
@@ -98,7 +98,7 @@ jobs:
 
       - name: Build
         run: |
-          ./configure
+          ./configure --enable-debugbuild
           make -j $(nproc) check-units installcheck
 
   check-units-sanitizers:
@@ -132,7 +132,7 @@ jobs:
 
       - name: Build
         run: |
-          ./configure CC=clang
+          ./configure --enable-debugbuild CC=clang
           make -j $(nproc) check-units installcheck
 
   check-fuzz:
@@ -165,7 +165,7 @@ jobs:
 
       - name: Build
         run: |
-          ./configure --enable-fuzzing CC=clang
+          ./configure --enable-debugbuild --enable-fuzzing CC=clang
           make -j $(nproc) check-fuzz
 
   compile:
@@ -215,7 +215,7 @@ jobs:
           pip3 install --user pip wheel poetry
           poetry export -o requirements.txt --with dev --without-hashes
           python3 -m pip install -r requirements.txt
-          ./configure CC="$COMPILER"
+          ./configure --enable-debugbuild CC="$COMPILER"
 
           make -j $(nproc) testpack.tar.bz2
 
@@ -462,7 +462,7 @@ jobs:
 
       - name: Build
         run: |
-          ./configure CC=clang --enable-address-sanitizer --enable-ub-sanitizer --disable-valgrind --enable-developer
+          ./configure CC=clang --enable-address-sanitizer --enable-ub-sanitizer --disable-valgrind --enable-developer --enable-debugbuild
           make -j $(nproc)
 
       - name: Test
diff --git a/Makefile b/Makefile
index b0b0aa6d3..39d883001 100644
--- a/Makefile
+++ b/Makefile
@@ -43,7 +43,7 @@ VG=VALGRIND=1 valgrind -q --error-exitcode=7
 VG_TEST_ARGS = --track-origins=yes --leak-check=full --show-reachable=yes --errors-for-leak-kinds=all
 endif
 
-ifeq ($(DEVELOPER),1)
+ifeq ($(DEBUGBUILD),1)
 DEV_CFLAGS=-DCCAN_TAKE_DEBUG=1 -DCCAN_TAL_DEBUG=1 -DCCAN_JSON_OUT_DEBUG=1
 else
 DEV_CFLAGS=
diff --git a/configure b/configure
index f138f9a51..8a5b00c1f 100755
--- a/configure
+++ b/configure
@@ -43,7 +43,7 @@ usage_with_default()
     echo "  $1 (default $DEF)"
 }
 
-# Given DEVELOPER, what COPTFLAGS do we default to.
+# Given DEBUGBUILD, what COPTFLAGS do we default to.
 default_coptflags()
 {
     if [ "$1" = 0 ]; then
@@ -142,6 +142,9 @@ set_defaults()
     CC=${CC:-cc}
     CDEBUGFLAGS=${CDEBUGFLAGS--std=gnu11 -g -fstack-protector-strong}
     DEVELOPER=${DEVELOPER:-0}
+    DEBUGBUILD=${DEBUGBUILD:-0}
+    # --enable-developer forces debug build
+    [ "$DEVELOPER" = 0 ] || DEBUGBUILD=1
     COMPAT=${COMPAT:-1}
     STATIC=${STATIC:-0}
     CLANG_COVERAGE=${CLANG_COVERAGE:-0}
@@ -152,13 +155,13 @@ set_defaults()
     CSANFLAGS=""
     if [ "$ASAN" != 0 ]; then
 	CSANFLAGS="$CSANFLAGS -fsanitize=address"
-	if [ "$DEVELOPER" != 0 ]; then
+	if [ "$DEBUGBUILD" != 0 ]; then
 	    CSANFLAGS="$CSANFLAGS -fno-sanitize-recover=address"
 	fi
     fi
     if [ "$UBSAN" != 0 ]; then
 	CSANFLAGS="$CSANFLAGS -fsanitize=undefined"
-	if [ "$DEVELOPER" != 0 ]; then
+	if [ "$DEBUGBUILD" != 0 ]; then
 	    CSANFLAGS="$CSANFLAGS -fno-sanitize-recover=undefined"
 	fi
     fi
@@ -168,7 +171,7 @@ set_defaults()
     fi
     echo CSANFLAGS = $CSANFLAGS
     PYTEST=${PYTEST-$(default_pytest)}
-    COPTFLAGS=${COPTFLAGS-$(default_coptflags "$DEVELOPER")}
+    COPTFLAGS=${COPTFLAGS-$(default_coptflags "$DEBUGBUILD")}
     CONFIGURATOR_CC=${CONFIGURATOR_CC-$CC}
     VALGRIND=${VALGRIND:-$(default_valgrind_setting)}
     TEST_NETWORK=${TEST_NETWORK:-regtest}
@@ -181,7 +184,7 @@ usage()
     echo "If --reconfigure is specified, $CONFIG_VAR_FILE will set defaults."
     echo "Default settings:"
     set_defaults
-    DEFAULT_COPTFLAGS="$(default_coptflags $DEVELOPER)"
+    DEFAULT_COPTFLAGS="$(default_coptflags $DEBUGBUILD)"
     # We assume we have a modern gcc.
     DEFAULT_CWARNFLAGS="$(default_cwarnflags ""$DEFAULT_COPTFLAGS"" 1 1)"
     usage_with_default "CC" "$CC"
@@ -198,6 +201,8 @@ usage()
     echo "    Prefix for make install"
     usage_with_default "--enable/disable-developer" "$DEVELOPER" "enable" "disable"
     echo "    Developer mode, good for testing"
+    usage_with_default "--enable/disable-debug" "$DEBUGBUILD" "enable" "disable"
+    echo "    Extra debug checks in the build, good for testing"
     usage_with_default "--enable/disable-compat" "$COMPAT" "enable" "disable"
     echo "    Compatibility mode, good to disable to see if your software breaks"
     usage_with_default "--enable/disable-valgrind" "(autodetect)"
@@ -236,20 +241,21 @@ for opt in "$@"; do
 	    # Set from values if not already set.
 	    while IFS='=' read VAR VAL; do
 		if eval [ -z \${$VAR+x} ]; then eval $VAR=\"$VAL\"; fi
+		# If they had an old config, it might set DEVELOPER.
 		if [ "$VAR" = DEVELOPER ]; then
+		    DEFAULT_COPTFLAGS=$(default_coptflags "$VAL")
+		    DEBUGBUILD="$VAL"
+		    VAR=DEBUGBUILD
+		fi
+		if [ "$VAR" = DEBUGBUILD ]; then
 		   DEFAULT_COPTFLAGS=$(default_coptflags "$VAL")
 		fi
 	    done < $CONFIG_VAR_FILE
 	    # If we were those defaults, unset so we get new defaults in
-	    # case DEVELOPER has changed.
+	    # case DEBUGBUILD has changed.
 	    if [ x"$COPTFLAGS" = x"$DEFAULT_COPTFLAGS" ]; then
 		unset COPTFLAGS
 	    fi
-	    # If they didn't have -Wshadow=local, add it on --reconfigure
-	    # (we only added it later)
-	    if [ x"${CWARNFLAGS%*-Wshadow=local}" = x"$CWARNFLAGS" ]; then
-		unset CWARNFLAGS
-	    fi
 	    ;;
 	CC=*) CC="${opt#CC=}";;
 	CONFIGURATOR_CC=*) CONFIGURATOR_CC="${opt#CONFIGURATOR_CC=}";;
@@ -260,6 +266,8 @@ for opt in "$@"; do
 	--prefix=*) PREFIX="${opt#--prefix=}";;
 	--enable-developer) DEVELOPER=1;;
 	--disable-developer) DEVELOPER=0;;
+	--enable-debugbuild) DEBUGBUILD=1;;
+	--disable-debugbuild) DEBUGBUILD=0;;
 	--enable-compat) COMPAT=1;;
 	--disable-compat) COMPAT=0;;
 	--enable-valgrind) VALGRIND=1;;
@@ -493,6 +501,7 @@ add_var POSTGRES_INCLUDE "$POSTGRES_INCLUDE"
 add_var POSTGRES_LDLIBS "$POSTGRES_LDLIBS"
 add_var VALGRIND "$VALGRIND"
 add_var DEVELOPER "$DEVELOPER" $CONFIG_HEADER.$$
+add_var DEBUGBUILD "$DEBUGBUILD"
 add_var COMPAT "$COMPAT" $CONFIG_HEADER.$$
 add_var PYTEST "$PYTEST"
 add_var STATIC "$STATIC"