diff --git a/configure.ac b/configure.ac
index 6ae0550c..9858a117 100644
--- a/configure.ac
+++ b/configure.ac
@@ -71,8 +71,6 @@ AC_ARG_ENABLE([omemo-qrcode],
     [AS_HELP_STRING([--enable-omemo-qrcode], [enable ability to display omemo qr code])])
 AC_ARG_ENABLE([coverage],
     [AS_HELP_STRING([--enable-coverage], [enable code coverage analysis])])
-AC_ARG_ENABLE([sanitizers],
-    [AS_HELP_STRING([--enable-sanitizers], [enable AddressSanitizer + UndefinedBehaviorSanitizer + unsigned-integer-overflow])])
 
 m4_include([m4/ax_valgrind_check.m4])
 AX_VALGRIND_DFLT([drd], [off])
@@ -399,8 +397,7 @@ AM_CFLAGS="$AM_CFLAGS -std=gnu99 -ggdb3"
 # GCC-specific warnings (not supported by clang) — test each one
 saved_CFLAGS="$CFLAGS"
 for _flag in -Wlogical-op -Wduplicated-cond -Wduplicated-branches \
-             -Wstringop-overflow -Warray-bounds=2 -Walloc-zero \
-             -Wsign-compare -Wconversion; do
+             -Wstringop-overflow -Warray-bounds=2 -Walloc-zero; do
     AC_MSG_CHECKING([whether $CC supports $_flag])
     CFLAGS="$saved_CFLAGS $_flag -Werror"
     AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
@@ -427,28 +424,11 @@ AS_IF([test "x$enable_coverage" = xyes],
      AM_LDFLAGS="$AM_LDFLAGS --coverage"
      AC_MSG_NOTICE([Code coverage analysis enabled])])
 
-AS_IF([test "x$enable_sanitizers" = xyes],
-    [SAN_FLAGS="-fsanitize=address,undefined,unsigned-integer-overflow -fno-sanitize-recover=all -fno-omit-frame-pointer"
-     AM_CFLAGS="$AM_CFLAGS $SAN_FLAGS"
-     AM_LDFLAGS="$AM_LDFLAGS -fsanitize=address,undefined"
-     AC_MSG_NOTICE([Sanitizers enabled: ASan + UBSan + unsigned-integer-overflow])])
-
 AS_IF([test "x$PACKAGE_STATUS" = xdevelopment],
-    [AM_CFLAGS="$AM_CFLAGS -Wunused -Werror"
-     # -Wsign-conversion and -Wsign-compare still emit ~230 warnings
-     # across the tree (mostly inherited from upstream). Keep them
-     # visible in build logs but let development builds continue;
-     # the plain narrowing / float-conversion categories are already
-     # clean and are kept as hard errors.
-     AM_CFLAGS="$AM_CFLAGS -Wno-error=sign-conversion -Wno-error=sign-compare"])
+    [AM_CFLAGS="$AM_CFLAGS -Wunused -Werror"])
 AS_IF([test "x$PLATFORM" = xosx],
     [AM_CFLAGS="$AM_CFLAGS -Qunused-arguments"])
 
-# Treat glib/gio headers as system so -Wconversion does not scream
-# about GPOINTER_TO_UINT etc. inside glibconfig.h.
-glib_CFLAGS=$(echo "$glib_CFLAGS" | sed 's/-I/-isystem /g')
-gio_CFLAGS=$(echo "$gio_CFLAGS" | sed 's/-I/-isystem /g')
-
 AM_CFLAGS="$AM_CFLAGS $PTHREAD_CFLAGS $glib_CFLAGS $gio_CFLAGS $curl_CFLAGS ${SQLITE_CFLAGS}"
 AM_CFLAGS="$AM_CFLAGS $libnotify_CFLAGS ${GTK_CFLAGS} $python_CFLAGS"
 AM_CFLAGS="$AM_CFLAGS -DTHEMES_PATH=\"\\\"$THEMES_PATH\\\"\" -DICONS_PATH=\"\\\"$ICONS_PATH\\\"\" -DGLOBAL_PYTHON_PLUGINS_PATH=\"\\\"$GLOBAL_PYTHON_PLUGINS_PATH\\\"\" -DGLOBAL_C_PLUGINS_PATH=\"\\\"$GLOBAL_C_PLUGINS_PATH\\\"\""