diff --git a/CHANGELOG.md b/CHANGELOG.md
index d102c7d..74021a7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -36,6 +36,10 @@
   “refreshed” it (https://codeberg.org/dnkl/yambar/issues/116).
 * network: failure to retrieve wireless attributes (SSID, RX/TX
   bitrate, signal strength etc).
+* Integer options that were supposed to be >= 0 were incorrectly
+  allowed, leading to various bad things; including yambar crashing,
+  or worse, the compositor crashing
+  (https://codeberg.org/dnkl/yambar/issues/129).
 
 
 ### Security
diff --git a/bar/wayland.c b/bar/wayland.c
index 90d1103..a5a6731 100644
--- a/bar/wayland.c
+++ b/bar/wayland.c
@@ -1025,7 +1025,8 @@ setup(struct bar *_bar)
         ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT |
         top_or_bottom);
 
-    update_size(backend);
+    if (!update_size(backend))
+        return false;
 
     assert(backend->monitor == NULL ||
            backend->width / backend->monitor->scale <= backend->monitor->width_px);
diff --git a/config-verify.c b/config-verify.c
index 63efef3..b92fb71 100644
--- a/config-verify.c
+++ b/config-verify.c
@@ -50,6 +50,17 @@ conf_verify_int(keychain_t *chain, const struct yml_node *node)
     return false;
 }
 
+bool
+conf_verify_unsigned(keychain_t *chain, const struct yml_node *node)
+{
+    if (yml_value_is_int(node) && yml_value_as_int(node) >= 0)
+        return true;
+
+    LOG_ERR("%s: value is not a positive integer: '%s'",
+            conf_err_prefix(chain, node), yml_value_as_string(node));
+    return false;
+}
+
 bool
 conf_verify_bool(keychain_t *chain, const struct yml_node *node)
 {
@@ -381,17 +392,17 @@ static bool
 verify_bar_border(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
-        {"width", false, &conf_verify_int},
-        {"left-width", false, &conf_verify_int},
-        {"right-width", false, &conf_verify_int},
-        {"top-width", false, &conf_verify_int},
-        {"bottom-width", false, &conf_verify_int},
+        {"width", false, &conf_verify_unsigned},
+        {"left-width", false, &conf_verify_unsigned},
+        {"right-width", false, &conf_verify_unsigned},
+        {"top-width", false, &conf_verify_unsigned},
+        {"bottom-width", false, &conf_verify_unsigned},
         {"color", false, &conf_verify_color},
-        {"margin", false, &conf_verify_int},
-        {"left-margin", false, &conf_verify_int},
-        {"right-margin", false, &conf_verify_int},
-        {"top-margin", false, &conf_verify_int},
-        {"bottom-margin", false, &conf_verify_int},
+        {"margin", false, &conf_verify_unsigned},
+        {"left-margin", false, &conf_verify_unsigned},
+        {"right-margin", false, &conf_verify_unsigned},
+        {"top-margin", false, &conf_verify_unsigned},
+        {"bottom-margin", false, &conf_verify_unsigned},
         {NULL, false, NULL},
     };
 
@@ -422,20 +433,20 @@ conf_verify_bar(const struct yml_node *bar)
     chain_push(&chain, "bar");
 
     static const struct attr_info attrs[] = {
-        {"height", true, &conf_verify_int},
+        {"height", true, &conf_verify_unsigned},
         {"location", true, &verify_bar_location},
         {"background", true, &conf_verify_color},
 
         {"monitor", false, &conf_verify_string},
         {"layer", false, &verify_bar_layer},
 
-        {"spacing", false, &conf_verify_int},
-        {"left-spacing", false, &conf_verify_int},
-        {"right-spacing", false, &conf_verify_int},
+        {"spacing", false, &conf_verify_unsigned},
+        {"left-spacing", false, &conf_verify_unsigned},
+        {"right-spacing", false, &conf_verify_unsigned},
 
-        {"margin", false, &conf_verify_int},
-        {"left-margin", false, &conf_verify_int},
-        {"right-margin", false, &conf_verify_int},
+        {"margin", false, &conf_verify_unsigned},
+        {"left-margin", false, &conf_verify_unsigned},
+        {"right-margin", false, &conf_verify_unsigned},
 
         {"border", false, &verify_bar_border},
         {"font", false, &conf_verify_font},
@@ -445,7 +456,7 @@ conf_verify_bar(const struct yml_node *bar)
         {"center", false, &verify_module_list},
         {"right", false, &verify_module_list},
 
-        {"trackpad-sensitivity", false, &conf_verify_int},
+        {"trackpad-sensitivity", false, &conf_verify_unsigned},
 
         {NULL, false, NULL},
     };
diff --git a/config-verify.h b/config-verify.h
index 5afe3f6..8e5ab29 100644
--- a/config-verify.h
+++ b/config-verify.h
@@ -32,6 +32,7 @@ const char *conf_err_prefix(
 
 bool conf_verify_string(keychain_t *chain, const struct yml_node *node);
 bool conf_verify_int(keychain_t *chain, const struct yml_node *node);
+bool conf_verify_unsigned(keychain_t *chain, const struct yml_node *node);
 bool conf_verify_bool(keychain_t *chain, const struct yml_node *node);
 
 bool conf_verify_enum(keychain_t *chain, const struct yml_node *node,
diff --git a/decorations/border.c b/decorations/border.c
index ac50c33..5868e88 100644
--- a/decorations/border.c
+++ b/decorations/border.c
@@ -76,7 +76,7 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
         {"color", true, &conf_verify_color},
-        {"size", false, &conf_verify_int},
+        {"size", false, &conf_verify_unsigned},
         DECORATION_COMMON_ATTRS,
     };
 
diff --git a/decorations/underline.c b/decorations/underline.c
index a700bec..5b8bbd3 100644
--- a/decorations/underline.c
+++ b/decorations/underline.c
@@ -54,7 +54,7 @@ static bool
 verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
-        {"size", true, &conf_verify_int},
+        {"size", true, &conf_verify_unsigned},
         {"color", true, &conf_verify_color},
         DECORATION_COMMON_ATTRS,
     };
diff --git a/doc/yambar-modules-script.5.scd b/doc/yambar-modules-script.5.scd
index 7ba46d8..c1f31c6 100644
--- a/doc/yambar-modules-script.5.scd
+++ b/doc/yambar-modules-script.5.scd
@@ -77,6 +77,7 @@ User defined.
 :  Arguments to pass to the script/binary.
 |  poll-interval
 :  integer
+:  no
 :  Number of seconds between each script run. If unset, continuous mode
    is used.
 
diff --git a/modules/battery.c b/modules/battery.c
index 4f17de4..e6526f5 100644
--- a/modules/battery.c
+++ b/modules/battery.c
@@ -496,7 +496,7 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
         {"name", true, &conf_verify_string},
-        {"poll-interval", false, &conf_verify_int},
+        {"poll-interval", false, &conf_verify_unsigned},
         MODULE_COMMON_ATTRS,
     };
 
diff --git a/modules/i3.c b/modules/i3.c
index 5e5c80a..0ed6927 100644
--- a/modules/i3.c
+++ b/modules/i3.c
@@ -878,9 +878,9 @@ static bool
 verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
-        {"spacing", false, &conf_verify_int},
-        {"left-spacing", false, &conf_verify_int},
-        {"right-spacing", false, &conf_verify_int},
+        {"spacing", false, &conf_verify_unsigned},
+        {"left-spacing", false, &conf_verify_unsigned},
+        {"right-spacing", false, &conf_verify_unsigned},
         {"sort", false, &verify_sort},
         {"persistent", false, &verify_persistent},
         {"content", true, &verify_content},
diff --git a/modules/mpd.c b/modules/mpd.c
index bebd401..274fdc8 100644
--- a/modules/mpd.c
+++ b/modules/mpd.c
@@ -616,7 +616,7 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
         {"host", true, &conf_verify_string},
-        {"port", false, &conf_verify_int},
+        {"port", false, &conf_verify_unsigned},
         MODULE_COMMON_ATTRS,
     };
 
diff --git a/modules/network.c b/modules/network.c
index 06ada9b..3bff716 100644
--- a/modules/network.c
+++ b/modules/network.c
@@ -1257,7 +1257,7 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
         {"name", true, &conf_verify_string},
-        {"poll-interval", false, &conf_verify_int},
+        {"poll-interval", false, &conf_verify_unsigned},
         MODULE_COMMON_ATTRS,
     };
 
diff --git a/modules/removables.c b/modules/removables.c
index 04d2695..3a54379 100644
--- a/modules/removables.c
+++ b/modules/removables.c
@@ -652,9 +652,9 @@ static bool
 verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
-        {"spacing", false, &conf_verify_int},
-        {"left-spacing", false, &conf_verify_int},
-        {"right-spacing", false, &conf_verify_int},
+        {"spacing", false, &conf_verify_unsigned},
+        {"left-spacing", false, &conf_verify_unsigned},
+        {"right-spacing", false, &conf_verify_unsigned},
         {"ignore", false, &verify_ignore},
         MODULE_COMMON_ATTRS,
     };
diff --git a/modules/script.c b/modules/script.c
index 2ddd722..254aac4 100644
--- a/modules/script.c
+++ b/modules/script.c
@@ -709,7 +709,7 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
     static const struct attr_info attrs[] = {
         {"path", true, &conf_verify_path},
         {"args", false, &conf_verify_args},
-        {"poll-interval", false, &conf_verify_int},
+        {"poll-interval", false, &conf_verify_unsigned},
         MODULE_COMMON_ATTRS,
     };
 
diff --git a/modules/sway-xkb.c b/modules/sway-xkb.c
index f4e7577..9841feb 100644
--- a/modules/sway-xkb.c
+++ b/modules/sway-xkb.c
@@ -374,9 +374,9 @@ static bool
 verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
-        {"spacing", false, &conf_verify_int},
-        {"left-spacing", false, &conf_verify_int},
-        {"right-spacing", false, &conf_verify_int},
+        {"spacing", false, &conf_verify_unsigned},
+        {"left-spacing", false, &conf_verify_unsigned},
+        {"right-spacing", false, &conf_verify_unsigned},
         {"identifiers", true, &verify_identifiers},
         MODULE_COMMON_ATTRS,
     };
diff --git a/particle.h b/particle.h
index 4ca520f..7c5685e 100644
--- a/particle.h
+++ b/particle.h
@@ -76,12 +76,12 @@ void exposable_default_on_mouse(
     enum mouse_event event, enum mouse_button btn, int x, int y);
 
 /* List of attributes *all* particles implement */
-#define PARTICLE_COMMON_ATTRS                      \
-    {"margin", false, &conf_verify_int},           \
-    {"left-margin", false, &conf_verify_int},      \
-    {"right-margin", false, &conf_verify_int},     \
-    {"on-click", false, &conf_verify_on_click},    \
-    {"font", false, &conf_verify_font},            \
-    {"foreground", false, &conf_verify_color},     \
-    {"deco", false, &conf_verify_decoration},      \
+#define PARTICLE_COMMON_ATTRS                           \
+    {"margin", false, &conf_verify_unsigned},           \
+    {"left-margin", false, &conf_verify_unsigned},      \
+    {"right-margin", false, &conf_verify_unsigned},     \
+    {"on-click", false, &conf_verify_on_click},         \
+    {"font", false, &conf_verify_font},                 \
+    {"foreground", false, &conf_verify_color},          \
+    {"deco", false, &conf_verify_decoration},           \
     {NULL, false, NULL}
diff --git a/particles/list.c b/particles/list.c
index 19ff15b..e5cf883 100644
--- a/particles/list.c
+++ b/particles/list.c
@@ -208,9 +208,9 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
         {"items", true, &conf_verify_particle_list_items},
-        {"spacing", false, &conf_verify_int},
-        {"left-spacing", false, &conf_verify_int},
-        {"right-spacing", false, &conf_verify_int},
+        {"spacing", false, &conf_verify_unsigned},
+        {"left-spacing", false, &conf_verify_unsigned},
+        {"right-spacing", false, &conf_verify_unsigned},
         PARTICLE_COMMON_ATTRS,
     };
 
diff --git a/particles/progress-bar.c b/particles/progress-bar.c
index ebc51c3..462d536 100644
--- a/particles/progress-bar.c
+++ b/particles/progress-bar.c
@@ -323,7 +323,7 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
         {"tag", true, &conf_verify_string},
-        {"length", true, &conf_verify_int},
+        {"length", true, &conf_verify_unsigned},
         /* TODO: make these optional? Default to empty */
         {"start", true, &conf_verify_particle},
         {"end", true, &conf_verify_particle},
diff --git a/particles/string.c b/particles/string.c
index c475d5b..f6083f6 100644
--- a/particles/string.c
+++ b/particles/string.c
@@ -323,7 +323,7 @@ verify_conf(keychain_t *chain, const struct yml_node *node)
 {
     static const struct attr_info attrs[] = {
         {"text", true, &conf_verify_string},
-        {"max", false, &conf_verify_int},
+        {"max", false, &conf_verify_unsigned},
         PARTICLE_COMMON_ATTRS,
     };