diff --git a/core/cthreads.c b/core/cthreads.c
index 843d2b98..36361a2a 100644
--- a/core/cthreads.c
+++ b/core/cthreads.c
@@ -103,9 +103,9 @@ unsigned long cthreads_thread_id(struct cthreads_thread thread) {
   #endif
 }
 
-void cthreads_thread_close(void *code) {
+void cthreads_thread_exit(void *code) {
   #ifdef _WIN32
-    #ifdef __WATCOMC__
+    #if defined  __WATCOMC__ || _MSC_VER || __DMC__
       ExitThread((DWORD)code);
     #else
       ExitThread((DWORD)(uintptr_t)code);
diff --git a/core/cthreads.h b/core/cthreads.h
index 8696292b..c63df962 100644
--- a/core/cthreads.h
+++ b/core/cthreads.h
@@ -224,14 +224,14 @@ struct cthreads_thread cthreads_thread_self(void);
 unsigned long cthreads_thread_id(struct cthreads_thread thread);
 
 /**
- * Closes a thread.
+ * Exits a thread.
  *
  * - pthread: pthread_exit
  * - windows threads: ExitThread
  *
  * @param code Pointer to the thread exit code.
  */
-void cthreads_thread_close(void *code);
+void cthreads_thread_exit(void *code);
 
 /**
  * Initializes a mutex.
diff --git a/core/threadpool.c b/core/threadpool.c
index 7710ed09..39f0a959 100644
--- a/core/threadpool.c
+++ b/core/threadpool.c
@@ -300,6 +300,6 @@ static void *threadpool_thread(void *threadpool)
     pool->started--;
 
     cthreads_mutex_unlock(&(pool->lock));
-    cthreads_thread_close(NULL);
+    cthreads_thread_exit(NULL);
     return(NULL);
 }
\ No newline at end of file
diff --git a/core/websockets.c b/core/websockets.c
index e6fbf310..3574e015 100644
--- a/core/websockets.c
+++ b/core/websockets.c
@@ -50,7 +50,11 @@ struct websockets {
     /** lock for functions that may be called in other threads */
     struct cthreads_mutex lock;
     /** lock for reading/writing the event-loop timestamp */
+    #ifdef CTHREADS_RWLOCK
     struct cthreads_rwlock rwlock;
+    #else
+    #error "pthread_rwlock functions are not available on this system."
+    #endif
 
     /**
      * user-triggered actions
diff --git a/examples/slash-commands2.c b/examples/slash-commands2.c
index 74e9556d..0539b93e 100644
--- a/examples/slash-commands2.c
+++ b/examples/slash-commands2.c
@@ -2,12 +2,12 @@
 #include <stdlib.h>
 #include <string.h>
 #include <strings.h>
-#include <pthread.h>
 #include <assert.h>
 #include <errno.h>
 #include <inttypes.h> /* SCNu64 */
 
 #include "discord.h"
+#include "cthreads.h"
 #include "log.h"
 
 u64snowflake g_app_id;
@@ -80,7 +80,7 @@ read_input(void *p_client)
     char cmd_action[9 + 1];
     CCORDcode code;
 
-    pthread_detach(pthread_self());
+    cthreads_thread_detach(cthreads_thread_self());
 
     while (1) {
         memset(buf, 0, sizeof(buf));
@@ -254,7 +254,7 @@ read_input(void *p_client)
         print_help();
     }
 
-    pthread_exit(NULL);
+    cthreads_thread_exit(NULL);
 }
 
 int
@@ -284,8 +284,9 @@ main(int argc, char *argv[])
         fscanf(stdin, "%" SCNu64, &g_app_id);
     } while (!g_app_id || errno == ERANGE);
 
-    pthread_t tid;
-    pthread_create(&tid, NULL, &read_input, client);
+    struct cthreads_thread tid;
+    struct cthreads_args args;
+    cthreads_thread_create(&tid, NULL, read_input, client, &args);
 
     discord_run(client);
 
diff --git a/include/discord-internal.h b/include/discord-internal.h
index e9eb083f..701538ee 100644
--- a/include/discord-internal.h
+++ b/include/discord-internal.h
@@ -780,7 +780,11 @@ struct discord_gateway {
          */
         int ping_ms;
         /** ping rwlock  */
+        #ifdef CTHREADS_RWLOCK
         struct cthreads_rwlock rwlock;
+        #else
+        #error "pthread_rwlock functions are not available on this system."
+        #endif
     } * timer;
 
     /** the identify structure for client authentication */
diff --git a/src/concord-once.c b/src/concord-once.c
index f9621c11..d50e1bf0 100644
--- a/src/concord-once.c
+++ b/src/concord-once.c
@@ -1,15 +1,15 @@
 #include <string.h>
 #include <signal.h>
 #include <curl/curl.h>
-#include <pthread.h>
 #include <unistd.h>
 #include <poll.h>
 #include <sys/ioctl.h>
 
 #include "error.h"
 #include "discord-worker.h"
+#include "cthreads.h"
 
-static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
+static struct cthreads_mutex lock;
 
 static int shutdown_fds[2] = {
     -1,
@@ -53,7 +53,9 @@ _ccord_sigint_handler(int signum)
 CCORDcode
 ccord_global_init()
 {
-    pthread_mutex_lock(&lock);
+    cthreads_mutex_init(&lock, NULL);
+
+    cthreads_mutex_lock(&lock);
     if (0 == init_counter++) {
 #ifdef CCORD_SIGINTCATCH
         signal(SIGINT, &_ccord_sigint_handler);
@@ -83,7 +85,7 @@ ccord_global_init()
             }
         }
     }
-    pthread_mutex_unlock(&lock);
+    cthreads_mutex_unlock(&lock);
     return CCORD_OK;
 
 fail_pipe_init:
@@ -99,14 +101,14 @@ ccord_global_init()
     curl_global_cleanup();
 
     init_counter = 0;
-    pthread_mutex_unlock(&lock);
+    cthreads_mutex_unlock(&lock);
     return CCORD_GLOBAL_INIT;
 }
 
 void
 ccord_global_cleanup()
 {
-    pthread_mutex_lock(&lock);
+    cthreads_mutex_lock(&lock);
     if (init_counter && 0 == --init_counter) {
         curl_global_cleanup();
         discord_worker_global_cleanup();
@@ -115,7 +117,7 @@ ccord_global_cleanup()
             shutdown_fds[i] = -1;
         }
     }
-    pthread_mutex_unlock(&lock);
+    cthreads_mutex_unlock(&lock);
 }
 
 int
@@ -130,5 +132,8 @@ discord_dup_shutdown_fd(void)
             fd = -1;
         }
     }
+
+    cthreads_mutex_destroy(&lock);
+
     return fd;
 }
diff --git a/src/discord-voice.c b/src/discord-voice.c
index d3b62db0..4a6c8d78 100644
--- a/src/discord-voice.c
+++ b/src/discord-voice.c
@@ -881,6 +881,7 @@ _discord_voice_cleanup(struct discord_voice *vc)
     if (vc->ws) ws_cleanup(vc->ws);
     if (vc->parse.pairs) free(vc->parse.pairs);
     if (vc->parse.tokens) free(vc->parse.tokens);
+    cthreads_mutex_destroy(&client_lock);
 }
 
 void
diff --git a/test/Makefile b/test/Makefile
index 3a594386..899922d4 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -6,7 +6,7 @@ INCLUDE_DIR   = $(TOP)/include
 GENCODECS_DIR = $(TOP)/gencodecs
 
 TEST_DISCORD = racecond rest timeout
-TEST_CORE    = user-agent websockets queriec
+TEST_CORE    = user-agent websockets queriec cthreads
 
 TESTS = $(TEST_DISCORD) $(TEST_GITHUB) $(TEST_CORE)
 
diff --git a/test/cthreads.c b/test/cthreads.c
index de9a553e..4d0d77e0 100644
--- a/test/cthreads.c
+++ b/test/cthreads.c
@@ -18,7 +18,7 @@ TEST create_thread() {
   ret = cthreads_thread_create(&thread, NULL, thread_func, NULL, &args);
   ASSERT_EQ(0, ret);
 
-  ret = cthreads_join(&thread, 0);
+  ret = cthreads_thread_join(thread, 0);
   ASSERT_EQ(0, ret);
 
   PASS();
@@ -70,10 +70,10 @@ TEST equal() {
   struct cthreads_thread thread2;
   int ret;
 
-  thread1 = cthreads_self();
-  thread2 = cthreads_self();
+  thread1 = cthreads_thread_self();
+  thread2 = cthreads_thread_self();
 
-  ret = cthreads_equal(thread1, thread2);
+  ret = cthreads_thread_equal(thread1, thread2);
   ASSERT_EQ(1, ret);
 
   PASS();