diff --git a/src/client.c b/src/client.c
index 53b0dff..94307b5 100644
--- a/src/client.c
+++ b/src/client.c
@@ -66,6 +66,7 @@ Client* wm_client_create(Wm *wm, Window w)
     XGetWMName(wm->display, w, &xtp);
 
     Client *c = calloc(1, sizeof(Client));
+    assert(c);
 
     c->next = NULL;
     c->prev = NULL;
@@ -81,6 +82,7 @@ Client* wm_client_create(Wm *wm, Window w)
         strln = strlen((char*)xtp.value);
         DEBUG_PRINT("%s allocating %d bytes for c->name\n", __func__, strln)
         c->name = malloc(strln+1);
+        assert(c->name);
         strcpy(c->name, (char*)xtp.value);
     }
 
diff --git a/src/config.c b/src/config.c
index 3fb7e46..a8f95e1 100644
--- a/src/config.c
+++ b/src/config.c
@@ -26,10 +26,12 @@ void wm_keybinds_init_def(Config *config)
 {
     char *st[] = {"st", NULL};
     char **sth = malloc(sizeof(st));
+    assert(sth);
     memcpy(sth, st, sizeof(st));
 
     char *dmenu[] = {"i3-dmenu-desktop", NULL};
     char **dmenuh = malloc(sizeof(dmenu));
+    assert(dmenuh);
     memcpy(dmenuh, dmenu, sizeof(dmenu));
     int size;
 
@@ -139,6 +141,7 @@ void wm_keybinds_init_def(Config *config)
     config->kb_count = size / sizeof(Keybind);
     DEBUG_PRINT("sizeof k: %d\n", size);
     config->keybinds = malloc(size);
+    assert(config->keybinds);
     memcpy(config->keybinds, k, size);
 }
 
@@ -178,6 +181,7 @@ void wm_configfile_init(ConfigFile *config, const char *filename)
     }
 
     config->available_commands = calloc(config->command_count, sizeof(ConfigCommand));
+    assert(config->available_commands);
     memcpy(config->available_commands, commands, sizeof(commands));
 }
 
@@ -337,14 +341,20 @@ void wm_configcommand_init(ConfigCommand *command)
 
     command->argv = calloc(CONFIG_ARGC_MAX, sizeof(void*));
     command->args = calloc(CONFIG_ARGC_MAX, sizeof(Arg));
+    assert(command->argv);
+    assert(command->args);
 
     for (size_t i = 0; i < CONFIG_ARGC_MAX; i++) {
         command->argv[i] = calloc(CONFIG_ARGLEN_MAX, 1);
         command->args[i].s = calloc(CONFIG_ARGLEN_MAX, 1);
         command->args[i].sl = calloc(CONFIG_ARGC_MAX, sizeof(char*));
+        assert(command->argv[i]);
+        assert(command->args[i].s);
+        assert(command->args[i].sl);
 
         for (size_t j = 0; j < CONFIG_ARGC_MAX; j++) {
             command->args[i].sl[j] = calloc(CONFIG_ARGLEN_MAX, 1);
+            assert(command->args[i].sl[j]);
         }
     }
 }
diff --git a/src/util.c b/src/util.c
index f371952..334e7cd 100644
--- a/src/util.c
+++ b/src/util.c
@@ -15,6 +15,7 @@ TreeNode* wm_treenode_new(NodeType type, TreeNode *parent)
 {
     DEBUG_PRINT("%s\n", __func__);
     TreeNode *node = calloc(sizeof(TreeNode), 1);
+    assert(node);
 
     node->parent = parent;
     node->type = type;
@@ -173,6 +174,7 @@ PtrArray wm_nonempty_workspaces_to_strptrarray(Wm *wm)
         TreeNode *node = wm->smon->workspaces[i].tree;
         if (!wm_treenode_is_empty(node) || (node->type == NODE_CLIENT && node->client)) {
             WmWorkspaceToStrRet *ws_str_with_index = malloc(sizeof(WmWorkspaceToStrRet));
+            assert(ws_str_with_index);
             *ws_str_with_index = (WmWorkspaceToStrRet) {
                 .ws_index = i,
                 .str = wm_treenode_to_str(wm->smon->workspaces[i].tree)
@@ -266,6 +268,7 @@ NodeArray* wm_postorder_traversal(TreeNode *tree)
     while (root != NULL || stack->size > 0) {
         if (root != NULL) {
             NodeWithIndex *n = malloc(sizeof(NodeWithIndex));
+            assert(n);
             n->node = root;
             n->index = root_index;
             wm_nodearray_push(stack, (void*)n);
@@ -558,9 +561,11 @@ TreeNode* wm_treenode_remove_client(Wm *wm, TreeNode *root, Client *client)
 NodeArray* wm_nodearray_new()
 {
     NodeArray *arr = calloc(1, sizeof(NodeArray));
+    assert(arr);
 
     arr->capacity = 10;
     arr->nodes = calloc(arr->capacity, sizeof(TreeNode*));
+    assert(arr->nodes);
     arr->size = 0;
 
     return arr;
@@ -574,12 +579,14 @@ void wm_nodearray_push(NodeArray *arr, TreeNode *node)
 
     if (arr->size >= arr->capacity) {
         TreeNode* temp = calloc(arr->capacity, sizeof(TreeNode*));
+        assert(temp);
         memcpy(temp, arr->nodes, arr->capacity * sizeof(TreeNode*));
         free(arr->nodes);
         size_t old_capacity = arr->capacity;
         arr->capacity = old_capacity * 2;
 
         arr->nodes = calloc(arr->capacity, sizeof(TreeNode*));
+        assert(arr->nodes);
         memcpy(arr->nodes, temp, old_capacity * sizeof(TreeNode*));
 
         free(temp);
@@ -663,6 +670,7 @@ PtrArray wm_ptrarray_new()
 
     arr.capacity = 10;
     arr.ptrs = calloc(arr.capacity, sizeof(void*));
+    assert(arr.ptrs);
     arr.size = 0;
 
     return arr;
@@ -676,12 +684,14 @@ void wm_ptrarray_push(PtrArray *arr, void* ptr)
 
     if (arr->size >= arr->capacity) {
         void* temp = calloc(arr->capacity, sizeof(void*));
+        assert(temp);
         memcpy(temp, arr->ptrs, arr->capacity * sizeof(void*));
         free(arr->ptrs);
         size_t old_capacity = arr->capacity;
         arr->capacity = old_capacity * 2;
 
         arr->ptrs = calloc(arr->capacity, sizeof(void*));
+        assert(arr->ptrs);
         memcpy(arr->ptrs, temp, old_capacity * sizeof(void*));
 
         free(temp);
diff --git a/src/wm.c b/src/wm.c
index 5f7ae55..8eeaf56 100644
--- a/src/wm.c
+++ b/src/wm.c
@@ -60,12 +60,14 @@ void wm_monitors_open_all(Wm *wm, Display *d)
 
     wm->wm_mc = count;
     wm->monitors = malloc(count * sizeof(Monitor));
+    assert(wm->monitors);
 
     for (int i = 0; i < count; i++) {
         wm->monitors[i] = wm_monitor_open(d, xsi[i]);
         //TODO: cfg
         wm->monitors[i].wscount = 9;
         wm->monitors[i].workspaces = calloc(wm->monitors[i].wscount, sizeof(Workspace));
+        assert(wm->monitors[i].workspaces);
         wm->monitors[i].selws = 0;
 
         for (size_t j = 0; j < wm->monitors[i].wscount; j++) {