diff --git a/ncat/http.c b/ncat/http.c
index e3eae16ad..6739378a2 100644
--- a/ncat/http.c
+++ b/ncat/http.c
@@ -89,7 +89,6 @@
 
 /* $Id$ */
 
-#include <assert.h>
 #include <string.h>
 
 #include "base64.h"
@@ -528,7 +527,7 @@ static const char *skip_crlf(const char *s)
     else if (*s == '\r' && *(s + 1) == '\n')
         return s + 2;
 
-    assert(0);
+    ncat_assert(0);
     return NULL;
 }
 
diff --git a/ncat/ncat_connect.c b/ncat/ncat_connect.c
index 5b0e278d9..8d6e1a8f8 100644
--- a/ncat/ncat_connect.c
+++ b/ncat/ncat_connect.c
@@ -102,7 +102,6 @@
 #include <unistd.h>
 #include <netdb.h>
 #endif
-#include <assert.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
@@ -164,7 +163,7 @@ static int verify_callback(int ok, X509_STORE_CTX *store)
         X509_NAME_print_ex_fp(stderr, X509_get_issuer_name(cert), 0, XN_FLAG_COMPAT);
         loguser_noprefix("\n");
 
-        assert(ssl_cert_fp_str_sha1(cert, digest_buf, sizeof(digest_buf)) != NULL);
+        ncat_assert(ssl_cert_fp_str_sha1(cert, digest_buf, sizeof(digest_buf)) != NULL);
         loguser("SHA-1 fingerprint: %s\n", digest_buf);
     }
 
@@ -227,7 +226,7 @@ static void connect_report(nsock_iod nsi)
             loguser("SSL connection to %s:%hu.", inet_socktop(&peer), nsi_peerport(nsi));
 
             cert = SSL_get_peer_certificate((SSL *) nsi_getssl(nsi));
-            assert(cert != NULL);
+            ncat_assert(cert != NULL);
 
             subject = X509_get_subject_name(cert);
             if (subject != NULL) {
@@ -241,7 +240,7 @@ static void connect_report(nsock_iod nsi)
 
             loguser_noprefix("\n");
 
-            assert(ssl_cert_fp_str_sha1(cert, digest_buf, sizeof(digest_buf)) != NULL);
+            ncat_assert(ssl_cert_fp_str_sha1(cert, digest_buf, sizeof(digest_buf)) != NULL);
             loguser("SHA-1 fingerprint: %s\n", digest_buf);
         } else {
 #if HAVE_SYS_UN_H
@@ -706,7 +705,7 @@ static void connect_handler(nsock_pool nsp, nsock_event evt, void *data)
     enum nse_status status = nse_status(evt);
     enum nse_type type = nse_type(evt);
 
-    assert(type == NSE_TYPE_CONNECT || type == NSE_TYPE_CONNECT_SSL);
+    ncat_assert(type == NSE_TYPE_CONNECT || type == NSE_TYPE_CONNECT_SSL);
 
     if (status == NSE_STATUS_ERROR) {
         loguser("%s.\n", socket_strerror(nse_errorcode(evt)));
@@ -715,7 +714,7 @@ static void connect_handler(nsock_pool nsp, nsock_event evt, void *data)
         loguser("%s.\n", socket_strerror(ETIMEDOUT));
         exit(1);
     } else {
-        assert(status == NSE_STATUS_SUCCESS);
+        ncat_assert(status == NSE_STATUS_SUCCESS);
     }
 
 #ifdef HAVE_OPENSSL
@@ -779,7 +778,7 @@ static void read_stdin_handler(nsock_pool nsp, nsock_event evt, void *data)
     char *buf, *tmp = NULL;
     int nbytes;
 
-    assert(type == NSE_TYPE_READ);
+    ncat_assert(type == NSE_TYPE_READ);
 
     if (status == NSE_STATUS_EOF) {
         if (o.sendonly) {
@@ -798,7 +797,7 @@ static void read_stdin_handler(nsock_pool nsp, nsock_event evt, void *data)
     } else if (status == NSE_STATUS_CANCELLED || status == NSE_STATUS_KILL) {
         return;
     } else {
-        assert(status == NSE_STATUS_SUCCESS);
+        ncat_assert(status == NSE_STATUS_SUCCESS);
     }
 
     buf = nse_readbuf(evt, &nbytes);
@@ -828,7 +827,7 @@ static void read_socket_handler(nsock_pool nsp, nsock_event evt, void *data)
     char *buf;
     int nbytes;
 
-    assert(type == NSE_TYPE_READ);
+    ncat_assert(type == NSE_TYPE_READ);
 
     if (status == NSE_STATUS_EOF) {
         nsock_loop_quit(nsp);
@@ -842,7 +841,7 @@ static void read_socket_handler(nsock_pool nsp, nsock_event evt, void *data)
     } else if (status == NSE_STATUS_CANCELLED || status == NSE_STATUS_KILL) {
         return;
     } else {
-        assert(status == NSE_STATUS_SUCCESS);
+        ncat_assert(status == NSE_STATUS_SUCCESS);
     }
 
     buf = nse_readbuf(evt, &nbytes);
@@ -867,7 +866,7 @@ static void write_socket_handler(nsock_pool nsp, nsock_event evt, void *data)
     enum nse_status status = nse_status(evt);
     enum nse_type type = nse_type(evt);
 
-    assert(type == NSE_TYPE_WRITE);
+    ncat_assert(type == NSE_TYPE_WRITE);
 
     if (status == NSE_STATUS_ERROR) {
         loguser("%s.\n", socket_strerror(nse_errorcode(evt)));
@@ -878,7 +877,7 @@ static void write_socket_handler(nsock_pool nsp, nsock_event evt, void *data)
     } else if (status == NSE_STATUS_CANCELLED || status == NSE_STATUS_KILL) {
         return;
     } else {
-        assert(status == NSE_STATUS_SUCCESS);
+        ncat_assert(status == NSE_STATUS_SUCCESS);
     }
 
     /* The write to the socket was successful. Allow reading more from stdin
@@ -891,12 +890,12 @@ static void idle_timer_handler(nsock_pool nsp, nsock_event evt, void *data)
     enum nse_status status = nse_status(evt);
     enum nse_type type = nse_type(evt);
 
-    assert(type == NSE_TYPE_TIMER);
+    ncat_assert(type == NSE_TYPE_TIMER);
 
     if (status == NSE_STATUS_CANCELLED || status == NSE_STATUS_KILL)
         return;
 
-    assert(status == NSE_STATUS_SUCCESS);
+    ncat_assert(status == NSE_STATUS_SUCCESS);
 
     loguser("Idle timeout expired (%d ms).\n", o.idletimeout);
 
diff --git a/ncat/ncat_core.c b/ncat/ncat_core.c
index 213dd6954..6da1bbc57 100644
--- a/ncat/ncat_core.c
+++ b/ncat/ncat_core.c
@@ -107,7 +107,6 @@
 #include <fcntl.h>
 #include <ctype.h>
 #include <time.h>
-#include <assert.h>
 
 /* Only two for now because we might have to listen on IPV4 and IPV6 */
 union sockaddr_u listenaddrs[NUM_LISTEN_ADDRS];
@@ -191,9 +190,9 @@ static int resolve_internal(const char *hostname, unsigned short port,
     char portbuf[16];
     int rc;
 
-    assert(hostname);
-    assert(ss);
-    assert(sslen);
+    ncat_assert(hostname != NULL);
+    ncat_assert(ss != NULL);
+    ncat_assert(sslen != NULL);
 
     memset(&hints, 0, sizeof(hints));
     hints.ai_family = af;
@@ -202,14 +201,14 @@ static int resolve_internal(const char *hostname, unsigned short port,
 
     /* Make the port number a string to give to getaddrinfo. */
     rc = Snprintf(portbuf, sizeof(portbuf), "%hu", port);
-    assert(rc >= 0 && (size_t) rc < sizeof(portbuf));
+    ncat_assert(rc >= 0 && (size_t) rc < sizeof(portbuf));
 
     rc = getaddrinfo(hostname, portbuf, &hints, &result);
     if (rc != 0)
         return rc;
     if (result == NULL)
         return EAI_NONAME;
-    assert(result->ai_addrlen > 0 && result->ai_addrlen <= (int) sizeof(struct sockaddr_storage));
+    ncat_assert(result->ai_addrlen > 0 && result->ai_addrlen <= (int) sizeof(struct sockaddr_storage));
     *sslen = result->ai_addrlen;
     memcpy(ss, result->ai_addr, *sslen);
     freeaddrinfo(result);
diff --git a/ncat/ncat_exec_win.c b/ncat/ncat_exec_win.c
index 10743e359..6efdc3269 100644
--- a/ncat/ncat_exec_win.c
+++ b/ncat/ncat_exec_win.c
@@ -89,8 +89,6 @@
 
 /* $Id$ */
 
-#include <assert.h>
-
 #include "ncat.h"
 
 /* This structure holds information about a subprocess with redirected input
@@ -186,11 +184,11 @@ extern void set_pseudo_sigchld_handler(void (*handler)(void))
 {
     if (pseudo_sigchld_mutex == NULL) {
         pseudo_sigchld_mutex = CreateMutex(NULL, FALSE, NULL);
-        assert(pseudo_sigchld_mutex != NULL);
+        ncat_assert(pseudo_sigchld_mutex != NULL);
     }
-    assert(WaitForSingleObject(pseudo_sigchld_mutex, INFINITE) == WAIT_OBJECT_0);
+    ncat_assert(WaitForSingleObject(pseudo_sigchld_mutex, INFINITE) == WAIT_OBJECT_0);
     pseudo_sigchld_handler = handler;
-    assert(ReleaseMutex(pseudo_sigchld_mutex) != 0);
+    ncat_assert(ReleaseMutex(pseudo_sigchld_mutex) != 0);
 }
 
 /* Run a command and redirect its input and output handles to a pair of
@@ -450,7 +448,7 @@ loop_end:
 
     WSACloseEvent(events[0]);
 
-    assert(unregister_subprocess(info->proc) != -1);
+    ncat_assert(unregister_subprocess(info->proc) != -1);
 
     GetExitCodeProcess(info->proc, &ret);
     if (ret == STILL_ACTIVE) {
@@ -472,10 +470,10 @@ loop_end:
     subprocess_info_close(info);
     free(info);
 
-    assert(WaitForSingleObject(pseudo_sigchld_mutex, INFINITE) == WAIT_OBJECT_0);
+    ncat_assert(WaitForSingleObject(pseudo_sigchld_mutex, INFINITE) == WAIT_OBJECT_0);
     if (pseudo_sigchld_handler != NULL)
         pseudo_sigchld_handler();
-    assert(ReleaseMutex(pseudo_sigchld_mutex) != 0);
+    ncat_assert(ReleaseMutex(pseudo_sigchld_mutex) != 0);
 
     return ret;
 }
@@ -488,7 +486,7 @@ static int get_subprocess_slot(void)
 {
     int i, free_index, max_index;
 
-    assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
+    ncat_assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
 
     free_index = -1;
     max_index = 0;
@@ -508,7 +506,7 @@ static int get_subprocess_slot(void)
         free_index = max_index++;
     subprocess_max_index = max_index;
 
-    assert(ReleaseMutex(subprocesses_mutex) != 0);
+    ncat_assert(ReleaseMutex(subprocesses_mutex) != 0);
 
     return free_index;
 }
@@ -523,14 +521,14 @@ static int register_subprocess(HANDLE proc)
 
     if (subprocesses_mutex == NULL) {
         subprocesses_mutex = CreateMutex(NULL, FALSE, NULL);
-        assert(subprocesses_mutex != NULL);
+        ncat_assert(subprocesses_mutex != NULL);
     }
     if (pseudo_sigchld_mutex == NULL) {
         pseudo_sigchld_mutex = CreateMutex(NULL, FALSE, NULL);
-        assert(pseudo_sigchld_mutex != NULL);
+        ncat_assert(pseudo_sigchld_mutex != NULL);
     }
 
-    assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
+    ncat_assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
 
     i = get_subprocess_slot();
     if (i == -1) {
@@ -551,7 +549,7 @@ static int register_subprocess(HANDLE proc)
         }
     }
 
-    assert(ReleaseMutex(subprocesses_mutex) != 0);
+    ncat_assert(ReleaseMutex(subprocesses_mutex) != 0);
 
     return i;
 }
@@ -562,7 +560,7 @@ static int unregister_subprocess(HANDLE proc)
 {
     int i;
 
-    assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
+    ncat_assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
 
     for (i = 0; i < subprocess_max_index; i++) {
         if (proc == subprocesses[i])
@@ -576,7 +574,7 @@ static int unregister_subprocess(HANDLE proc)
         i = -1;
     }
 
-    assert(ReleaseMutex(subprocesses_mutex) != 0);
+    ncat_assert(ReleaseMutex(subprocesses_mutex) != 0);
 
     return i;
 }
@@ -588,7 +586,7 @@ static void terminate_subprocesses(void)
     if (o.debug)
         logdebug("Terminating subprocesses\n");
 
-    assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
+    ncat_assert(WaitForSingleObject(subprocesses_mutex, INFINITE) == WAIT_OBJECT_0);
 
     if (o.debug > 1)
         logdebug("max_index %d\n", subprocess_max_index);
@@ -607,7 +605,7 @@ static void terminate_subprocesses(void)
         subprocesses[i] = NULL;
     }
 
-    assert(ReleaseMutex(subprocesses_mutex) != 0);
+    ncat_assert(ReleaseMutex(subprocesses_mutex) != 0);
 }
 
 static void sigint_handler(int s)
diff --git a/ncat/ncat_listen.c b/ncat/ncat_listen.c
index 2c0b948e3..3a4a0acee 100644
--- a/ncat/ncat_listen.c
+++ b/ncat/ncat_listen.c
@@ -91,7 +91,6 @@
 
 #include "ncat.h"
 
-#include <assert.h>
 #include <errno.h>
 #include <signal.h>
 #include <stdio.h>
@@ -183,7 +182,7 @@ static int get_conn_count(void)
         conn_dec_changed = 0;
         count = conn_inc - conn_dec;
     } while (conn_dec_changed);
-    assert(count <= INT_MAX);
+    ncat_assert(count <= INT_MAX);
 
     return count;
 }
diff --git a/ncat/ncat_posix.c b/ncat/ncat_posix.c
index 9dbb4f09b..afac3f333 100644
--- a/ncat/ncat_posix.c
+++ b/ncat/ncat_posix.c
@@ -89,8 +89,6 @@
 
 /* $Id$ */
 
-#include <assert.h>
-
 #include "ncat.h"
 
 char **cmdline_split(const char *cmdexec);
@@ -350,7 +348,7 @@ int ssl_load_default_ca_certs(SSL_CTX *ctx)
         logdebug("Using system default trusted CA certificates and those in %s.\n", NCAT_CA_CERTS_PATH);
 
     /* Load distribution-provided defaults, if any. */
-    assert(SSL_CTX_set_default_verify_paths(ctx) > 0);
+    ncat_assert(SSL_CTX_set_default_verify_paths(ctx) > 0);
 
     /* Also load the trusted certificates we ship. */
     rc = SSL_CTX_load_verify_locations(ctx, NCAT_CA_CERTS_PATH, NULL);
diff --git a/ncat/ncat_ssl.c b/ncat/ncat_ssl.c
index 61c165f6c..d7a94b5f5 100644
--- a/ncat/ncat_ssl.c
+++ b/ncat/ncat_ssl.c
@@ -95,7 +95,6 @@
 #include "nsock.h"
 #include "ncat.h"
 
-#include <assert.h>
 #include <stdio.h>
 #include <openssl/ssl.h>
 #include <openssl/err.h>
@@ -160,7 +159,7 @@ SSL_CTX *setup_ssl_listen(void)
         if (ssl_gen_cert(&cert, &key) == 0)
             bye("ssl_gen_cert(): %s.", ERR_error_string(ERR_get_error(), NULL));
         if (o.verbose) {
-            assert(ssl_cert_fp_str_sha1(cert, digest_buf, sizeof(digest_buf)) != NULL);
+            ncat_assert(ssl_cert_fp_str_sha1(cert, digest_buf, sizeof(digest_buf)) != NULL);
             loguser("SHA-1 fingerprint: %s\n", digest_buf);
         }
         if (SSL_CTX_use_certificate(sslctx, cert) != 1)
@@ -562,7 +561,7 @@ char *ssl_cert_fp_str_sha1(const X509 *cert, char *strbuf, size_t len)
         Snprintf(p, 3, "%02X", binbuf[i]);
         p += 2;
     }
-    assert(p - strbuf <= len);
+    ncat_assert(p - strbuf <= len);
     *p = '\0';
 
     return strbuf;
diff --git a/ncat/test/test-wildcard.c b/ncat/test/test-wildcard.c
index cbcaa99d5..f675adc00 100644
--- a/ncat/test/test-wildcard.c
+++ b/ncat/test/test-wildcard.c
@@ -7,7 +7,6 @@ dNSNames, then checks that matching names are accepted and non-matching names
 are rejected. The SSL transactions happen over OpenSSL BIO pairs.
 */
 
-#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -68,28 +67,28 @@ static int test(const struct lstr commonNames[], const struct lstr dNSNames[],
 
     tests_run++;
 
-    assert(gen_cert(&cert, &key, commonNames, dNSNames) == 1);
+    ncat_assert(gen_cert(&cert, &key, commonNames, dNSNames) == 1);
 
-    assert(BIO_new_bio_pair(&server_bio, 0, &client_bio, 0) == 1);
+    ncat_assert(BIO_new_bio_pair(&server_bio, 0, &client_bio, 0) == 1);
 
     server_ctx = SSL_CTX_new(SSLv23_server_method());
-    assert(server_ctx != NULL);
+    ncat_assert(server_ctx != NULL);
 
     client_ctx = SSL_CTX_new(SSLv23_client_method());
-    assert(client_ctx != NULL);
+    ncat_assert(client_ctx != NULL);
     SSL_CTX_set_verify(client_ctx, SSL_VERIFY_PEER, NULL);
     SSL_CTX_set_verify_depth(client_ctx, 1);
     ssl_ctx_trust_cert(client_ctx, cert);
 
     server_ssl = SSL_new(server_ctx);
-    assert(server_ssl != NULL);
+    ncat_assert(server_ssl != NULL);
     SSL_set_accept_state(server_ssl);
     SSL_set_bio(server_ssl, server_bio, server_bio);
-    assert(SSL_use_certificate(server_ssl, cert) == 1);
-    assert(SSL_use_PrivateKey(server_ssl, key) == 1);
+    ncat_assert(SSL_use_certificate(server_ssl, cert) == 1);
+    ncat_assert(SSL_use_PrivateKey(server_ssl, key) == 1);
 
     client_ssl = SSL_new(client_ctx);
-    assert(client_ssl != NULL);
+    ncat_assert(client_ssl != NULL);
     SSL_set_connect_state(client_ssl);
     SSL_set_bio(client_ssl, client_bio, client_bio);
 
@@ -530,7 +529,7 @@ void test_specificity(const struct lstr patterns[],
 
     for (i = 0; i < ARR_LEN && !is_sentinel(&patterns[i]); i++)
         scratch[i] = patterns[i];
-    assert(i < ARR_LEN);
+    ncat_assert(i < ARR_LEN);
     scratch[i] = lstr_sentinel;
 
     test(scratch, NULL, test_names, expected_forward);
diff --git a/ncat/util.c b/ncat/util.c
index 057c84358..2e2bd547e 100644
--- a/ncat/util.c
+++ b/ncat/util.c
@@ -95,7 +95,6 @@
 #include "nbase.h"
 #include "sockaddr_u.h"
 
-#include <assert.h>
 #include <stdio.h>
 #ifdef WIN32
 #include <iphlpapi.h>
@@ -212,7 +211,7 @@ void zmem(void *mem, size_t n)
    buffer and updates the variables to make room if necessary. */
 int strbuf_append(char **buf, size_t *size, size_t *offset, const char *s, size_t n)
 {
-    assert(*offset <= *size);
+    ncat_assert(*offset <= *size);
 
     if (n >= *size - *offset) {
         *size += n + 1;
@@ -239,7 +238,7 @@ int strbuf_sprintf(char **buf, size_t *size, size_t *offset, const char *fmt, ..
     va_list va;
     int n;
 
-    assert(*offset <= *size);
+    ncat_assert(*offset <= *size);
 
     if (*buf == NULL) {
         *size = 1;