diff --git a/bar.c b/bar.c
index 5020a71..c839567 100644
--- a/bar.c
+++ b/bar.c
@@ -101,21 +101,21 @@ expose(const struct bar *_bar)
 
     struct module_expose_context ctx_left[bar->left.count];
     for (size_t i = 0; i < bar->left.count; i++) {
-        const struct module *m = bar->left.mods[i];
+        struct module *m = bar->left.mods[i];
         ctx_left[i] = m->begin_expose(m, bar->cairo);
         left_width += bar->left_spacing + ctx_left[i].width + bar->right_spacing;
     }
 
     struct module_expose_context ctx_center[bar->center.count];
     for (size_t i = 0; i < bar->center.count; i++) {
-        const struct module *m = bar->center.mods[i];
+        struct module *m = bar->center.mods[i];
         ctx_center[i] = m->begin_expose(m, bar->cairo);
         center_width += bar->left_spacing + ctx_center[i].width + bar->right_spacing;
     }
 
     struct module_expose_context ctx_right[bar->right.count];
     for (size_t i = 0; i < bar->right.count; i++) {
-        const struct module *m = bar->right.mods[i];
+        struct module *m = bar->right.mods[i];
         ctx_right[i] = m->begin_expose(m, bar->cairo);
         right_width += bar->left_spacing + ctx_right[i].width + bar->right_spacing;
     }
diff --git a/module.c b/module.c
index af66538..9dcf5d5 100644
--- a/module.c
+++ b/module.c
@@ -25,7 +25,7 @@ module_default_destroy(struct module *mod)
 }
 
 struct module_expose_context
-module_default_begin_expose(const struct module *mod, cairo_t *cr)
+module_default_begin_expose(struct module *mod, cairo_t *cr)
 {
     struct exposable *e = mod->content(mod);
     return (struct module_expose_context){
diff --git a/module.h b/module.h
index b7a9620..18314fc 100644
--- a/module.h
+++ b/module.h
@@ -29,8 +29,8 @@ struct module {
     int (*run)(struct module_run_context *ctx);
     void (*destroy)(struct module *module);
 
-    struct exposable *(*content)(const struct module *mod);
-    struct module_expose_context (*begin_expose)(const struct module *mod, cairo_t *cr);
+    struct exposable *(*content)(struct module *mod);
+    struct module_expose_context (*begin_expose)(struct module *mod, cairo_t *cr);
     void (*expose)(const struct module *mod,
                    const struct module_expose_context *ctx,
                    cairo_t *cr, int x, int y, int height);
@@ -42,7 +42,7 @@ struct module *module_common_new(void);
 void module_default_destroy(struct module *mod);
 
 struct module_expose_context module_default_begin_expose(
-    const struct module *mod, cairo_t *cr);
+    struct module *mod, cairo_t *cr);
 
 void module_default_expose(
     const struct module *mod,
diff --git a/modules/battery/battery.c b/modules/battery/battery.c
index 24c7dc2..3792ea2 100644
--- a/modules/battery/battery.c
+++ b/modules/battery/battery.c
@@ -49,11 +49,11 @@ destroy(struct module *mod)
 }
 
 static struct exposable *
-content(const struct module *mod)
+content(struct module *mod)
 {
     const struct private *m = mod->private;
 
-    mtx_lock(&((struct module *)mod)->lock);
+    mtx_lock(&mod->lock);
 
     assert(m->state == STATE_FULL ||
            m->state == STATE_CHARGING ||
@@ -92,7 +92,7 @@ content(const struct module *mod)
         .count = 6,
     };
 
-    mtx_unlock(&((struct module *)mod)->lock);
+    mtx_unlock(&mod->lock);
 
     struct exposable *exposable = m->label->instantiate(m->label, &tags);
 
diff --git a/modules/clock/clock.c b/modules/clock/clock.c
index 529b886..4680a03 100644
--- a/modules/clock/clock.c
+++ b/modules/clock/clock.c
@@ -21,7 +21,7 @@ destroy(struct module *mod)
 }
 
 static struct exposable *
-content(const struct module *mod)
+content(struct module *mod)
 {
     const struct private *m = mod->private;
     time_t t = time(NULL);
diff --git a/modules/i3/i3.c b/modules/i3/i3.c
index 34617a8..c9cff0c 100644
--- a/modules/i3/i3.c
+++ b/modules/i3/i3.c
@@ -397,7 +397,7 @@ destroy(struct module *mod)
 }
 
 static struct exposable *
-content(const struct module *mod)
+content(struct module *mod)
 {
     struct private *m = mod->private;
 
diff --git a/modules/label/label.c b/modules/label/label.c
index afc0b6b..c215380 100644
--- a/modules/label/label.c
+++ b/modules/label/label.c
@@ -19,7 +19,7 @@ destroy(struct module *mod)
 }
 
 static struct exposable *
-content(const struct module *mod)
+content(struct module *mod)
 {
     const struct private *m = mod->private;
     return m->label->instantiate(m->label, NULL);
diff --git a/modules/xkb/xkb.c b/modules/xkb/xkb.c
index adbbed8..1087e48 100644
--- a/modules/xkb/xkb.c
+++ b/modules/xkb/xkb.c
@@ -52,7 +52,7 @@ destroy(struct module *mod)
 }
 
 static struct exposable *
-content(const struct module *mod)
+content(struct module *mod)
 {
     const struct private *m = mod->private;
 
diff --git a/modules/xwindow/xwindow.c b/modules/xwindow/xwindow.c
index 9a16d92..5779e14 100644
--- a/modules/xwindow/xwindow.c
+++ b/modules/xwindow/xwindow.c
@@ -255,7 +255,7 @@ run(struct module_run_context *ctx)
 }
 
 static struct exposable *
-content(const struct module *mod)
+content(struct module *mod)
 {
     struct private *m = mod->private;