diff --git a/tests/scripts/generate_tls13_compat_tests.py b/tests/scripts/generate_tls13_compat_tests.py
index d67c222..3b139b3 100755
--- a/tests/scripts/generate_tls13_compat_tests.py
+++ b/tests/scripts/generate_tls13_compat_tests.py
@@ -275,6 +275,232 @@
         return ret
 
 
+class MbedTLSServ(TLSProgram):
+    """
+    Generate test commands for mbedTLS server.
+    """
+
+    CIPHER_SUITE = {
+        'TLS_AES_256_GCM_SHA384': 'TLS1-3-AES-256-GCM-SHA384',
+        'TLS_AES_128_GCM_SHA256': 'TLS1-3-AES-128-GCM-SHA256',
+        'TLS_CHACHA20_POLY1305_SHA256': 'TLS1-3-CHACHA20-POLY1305-SHA256',
+        'TLS_AES_128_CCM_SHA256': 'TLS1-3-AES-128-CCM-SHA256',
+        'TLS_AES_128_CCM_8_SHA256': 'TLS1-3-AES-128-CCM-8-SHA256'}
+
+    def cmd(self):
+        super().cmd()
+        ret = ['$P_SRV_NO_CERT']
+        ret += ['server_addr=127.0.0.1', 'server_port=$SRV_PORT',
+                'debug_level=4', 'force_version=tls13']
+        for _, cert, key in map(lambda sig_alg: CERTIFICATES[sig_alg], self._cert_sig_algs):
+            ret += ['crt_file={cert} key_file={key}'.format(cert=cert, key=key)]
+        ret += ['ca_file={cafile}'.format(
+            cafile=CERTIFICATES[self._cert_sig_algs[0]].cafile)]
+
+        if self._ciphers:
+            ciphers = ','.join(
+                map(lambda cipher: self.CIPHER_SUITE[cipher], self._ciphers))
+            ret += ["force_ciphersuite={ciphers}".format(ciphers=ciphers)]
+
+        if self._sig_algs + self._cert_sig_algs:
+            ret += ['sig_algs={sig_algs}'.format(
+                sig_algs=','.join(set(self._sig_algs + self._cert_sig_algs)))]
+
+        if self._named_groups:
+            named_groups = ','.join(self._named_groups)
+            ret += ["curves={named_groups}".format(named_groups=named_groups)]
+
+        ret += ['tls13_kex_modes=ephemeral cookies=0 tickets=0']
+        ret = ' '.join(ret)
+        return ret
+
+    def pre_checks(self):
+        ret = ['requires_config_enabled MBEDTLS_DEBUG_C',
+               'requires_config_enabled MBEDTLS_SSL_CLI_C',
+               'requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3']
+
+        if self._compat_mode:
+            ret += ['requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE']
+
+        if 'rsa_pss_rsae_sha256' in self._sig_algs + self._cert_sig_algs:
+            ret.append(
+                'requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT')
+        return ret
+
+    def post_checks(self):
+        check_strings = ["Protocol is TLSv1.3"]
+        if self._ciphers:
+            check_strings.append(
+                "server hello, chosen ciphersuite: {} ( id={:04d} )".format(
+                    self.CIPHER_SUITE[self._ciphers[0]],
+                    CIPHER_SUITE_IANA_VALUE[self._ciphers[0]]))
+        if self._sig_algs:
+            check_strings.append(
+                "received signature algorithm: 0x{:x}".format(
+                    SIG_ALG_IANA_VALUE[self._sig_algs[0]]))
+
+        for named_group in self._named_groups:
+            check_strings += ['got named group: {named_group}({iana_value:04x})'.format(
+                                named_group=named_group,
+                                iana_value=NAMED_GROUP_IANA_VALUE[named_group])]
+
+        check_strings.append("Verifying peer X.509 certificate... ok")
+        return ['-s "{}"'.format(i) for i in check_strings]
+
+
+class OpenSSLCli(TLSProgram):
+    """
+    Generate test commands for OpenSSL client.
+    """
+
+    NAMED_GROUP = {
+        'secp256r1': 'P-256',
+        'secp384r1': 'P-384',
+        'secp521r1': 'P-521',
+        'x25519': 'X25519',
+        'x448': 'X448',
+    }
+
+    def cmd(self):
+        super().cmd()
+        ret = ['$O_NEXT_CLI_NO_CERT']
+        for _, cert, key in map(lambda sig_alg: CERTIFICATES[sig_alg], self._cert_sig_algs):
+            ret += ['-cert {cert} -key {key}'.format(cert=cert, key=key)]
+
+        ret += ['-CAfile {cafile}'.format(
+            cafile=CERTIFICATES[self._cert_sig_algs[0]].cafile)]
+
+        if self._ciphers:
+            ciphersuites = ':'.join(self._ciphers)
+            ret += ["-ciphersuites {ciphersuites}".format(ciphersuites=ciphersuites)]
+
+        if self._sig_algs:
+            signature_algorithms = set(self._sig_algs + self._cert_sig_algs)
+            signature_algorithms = ':'.join(signature_algorithms)
+            ret += ["-sigalgs {signature_algorithms}".format(
+                signature_algorithms=signature_algorithms)]
+
+        if self._named_groups:
+            named_groups = ':'.join(
+                map(lambda named_group: self.NAMED_GROUP[named_group], self._named_groups))
+            ret += ["-groups {named_groups}".format(named_groups=named_groups)]
+
+        ret += ['-msg -tls1_3']
+        if not self._compat_mode:
+            ret += ['-no_middlebox']
+
+        return ' '.join(ret)
+
+    def pre_checks(self):
+        return ["requires_openssl_tls1_3"]
+
+    def post_checks(self):
+        return ['-s "HTTP/1.0 200 OK"']
+
+
+class GnuTLSCli(TLSProgram):
+    """
+    Generate test commands for GnuTLS client.
+    """
+
+    CIPHER_SUITE = {
+        'TLS_AES_256_GCM_SHA384': [
+            'AES-256-GCM',
+            'SHA384',
+            'AEAD'],
+        'TLS_AES_128_GCM_SHA256': [
+            'AES-128-GCM',
+            'SHA256',
+            'AEAD'],
+        'TLS_CHACHA20_POLY1305_SHA256': [
+            'CHACHA20-POLY1305',
+            'SHA256',
+            'AEAD'],
+        'TLS_AES_128_CCM_SHA256': [
+            'AES-128-CCM',
+            'SHA256',
+            'AEAD'],
+        'TLS_AES_128_CCM_8_SHA256': [
+            'AES-128-CCM-8',
+            'SHA256',
+            'AEAD']}
+
+    SIGNATURE_ALGORITHM = {
+        'ecdsa_secp256r1_sha256': ['SIGN-ECDSA-SECP256R1-SHA256'],
+        'ecdsa_secp521r1_sha512': ['SIGN-ECDSA-SECP521R1-SHA512'],
+        'ecdsa_secp384r1_sha384': ['SIGN-ECDSA-SECP384R1-SHA384'],
+        'rsa_pss_rsae_sha256': ['SIGN-RSA-PSS-RSAE-SHA256']}
+
+    NAMED_GROUP = {
+        'secp256r1': ['GROUP-SECP256R1'],
+        'secp384r1': ['GROUP-SECP384R1'],
+        'secp521r1': ['GROUP-SECP521R1'],
+        'x25519': ['GROUP-X25519'],
+        'x448': ['GROUP-X448'],
+    }
+
+    def pre_checks(self):
+        return ["requires_gnutls_tls1_3",
+                "requires_gnutls_next_no_ticket",
+                "requires_gnutls_next_disable_tls13_compat", ]
+
+    def post_checks(self):
+        return ['-c "HTTP/1.0 200 OK"']
+
+    def cmd(self):
+        super().cmd()
+        ret = ['$G_NEXT_CLI_NO_CERT', '--debug=4']
+        ret += ['localhost', '-p $SRV_PORT', '--single-key-share']
+        ret += ['--x509cafile {cafile}'.format(
+            cafile=CERTIFICATES[self._cert_sig_algs[0]].cafile)]
+
+        for _, cert, key in map(lambda sig_alg: CERTIFICATES[sig_alg], self._cert_sig_algs):
+            ret += ['--x509certfile {cert} --x509keyfile {key}'.format(
+                cert=cert, key=key)]
+
+        priority_string_list = []
+
+        def update_priority_string_list(items, map_table):
+            for item in items:
+                for i in map_table[item]:
+                    if i not in priority_string_list:
+                        yield i
+
+        if self._ciphers:
+            priority_string_list.extend(update_priority_string_list(
+                self._ciphers, self.CIPHER_SUITE))
+        else:
+            priority_string_list.extend(['CIPHER-ALL', 'MAC-ALL'])
+
+        if self._sig_algs:
+            signature_algorithms = set(self._sig_algs + self._cert_sig_algs)
+            priority_string_list.extend(update_priority_string_list(
+                signature_algorithms, self.SIGNATURE_ALGORITHM))
+        else:
+            priority_string_list.append('SIGN-ALL')
+
+
+        if self._named_groups:
+            priority_string_list.extend(update_priority_string_list(
+                self._named_groups, self.NAMED_GROUP))
+        else:
+            priority_string_list.append('GROUP-ALL')
+
+        priority_string_list = ['NONE'] + \
+            priority_string_list + ['VERS-TLS1.3']
+
+        priority_string = ':+'.join(priority_string_list)
+        priority_string += ':%NO_TICKETS'
+
+        if not self._compat_mode:
+            priority_string += [':%DISABLE_TLS13_COMPAT_MODE']
+
+        ret += ['--priority={priority_string}'.format(
+            priority_string=priority_string)]
+        ret = ' '.join(ret)
+        return ret
+
+
 class MbedTLSCli(TLSProgram):
     """
     Generate test commands for mbedTLS client.
@@ -348,6 +574,8 @@
 SERVER_CLASSES = {'OpenSSL': OpenSSLServ, 'GnuTLS': GnuTLSServ}
 CLIENT_CLASSES = {'mbedTLS': MbedTLSCli}
 
+SERVER_SERVER_CLASSES = {'mbedTLS': MbedTLSServ}
+SERVER_CLIENT_CLASSES = {'OpenSSL': OpenSSLCli, 'GnuTLS': GnuTLSCli, 'mbedTLS': MbedTLSCli}
 
 def generate_compat_test(client=None, server=None, cipher=None, named_group=None, sig_alg=None):
     """
@@ -375,6 +603,33 @@
     return '\n'.join(server_object.pre_checks() + client_object.pre_checks() + [cmd])
 
 
+def generate_server_side_compat_test(client=None, server=None, cipher=None,
+                                     named_group=None, sig_alg=None):
+    """
+    Generate server side test case with `ssl-opt.sh` format.
+    """
+    name = 'TLS 1.3 server side {client[0]}->{server[0]}: {cipher},{named_group},{sig_alg}'.format(
+        client=client, server=server, cipher=cipher[4:], sig_alg=sig_alg, named_group=named_group)
+
+    server_object = SERVER_SERVER_CLASSES[server](ciphersuite=cipher,
+                                                  named_group=named_group,
+                                                  signature_algorithm=sig_alg,
+                                                  cert_sig_alg=sig_alg)
+    client_object = SERVER_CLIENT_CLASSES[client](ciphersuite=cipher,
+                                                  named_group=named_group,
+                                                  signature_algorithm=sig_alg,
+                                                  cert_sig_alg=sig_alg)
+
+    cmd = ['run_test "{}"'.format(name), '"{}"'.format(
+        server_object.cmd()), '"{}"'.format(client_object.cmd()), '0']
+    cmd += server_object.post_checks()
+    cmd += client_object.post_checks()
+    cmd += ['-C "received HelloRetryRequest message"']
+    prefix = ' \\\n' + (' '*9)
+    cmd = prefix.join(cmd)
+    return '\n'.join(server_object.pre_checks() + client_object.pre_checks() + [cmd])
+
+
 def generate_hrr_compat_test(client=None, server=None,
                              client_named_group=None, server_named_group=None,
                              cert_sig_alg=None):
@@ -404,6 +659,32 @@
                      client_object.pre_checks() +
                      [cmd])
 
+def generate_server_hrr_compat_test(client=None, server=None,
+                                    client_named_group=None, server_named_group=None,
+                                    cert_sig_alg=None):
+    """
+    Generate server side Hello Retry Request test case with `ssl-opt.sh` format.
+    """
+    name = 'TLS 1.3 {client[0]}->{server[0]}: Server HRR {c_named_group} -> {s_named_group}'.format(
+        client=client, server=server, c_named_group=client_named_group,
+        s_named_group=server_named_group)
+    server_object = SERVER_SERVER_CLASSES[server](named_group=server_named_group,
+                                                  cert_sig_alg=cert_sig_alg)
+
+    client_object = SERVER_CLIENT_CLASSES[client](named_group=client_named_group,
+                                                  cert_sig_alg=cert_sig_alg)
+    client_object.add_named_groups(server_named_group)
+
+    cmd = ['run_test "{}"'.format(name), '"{}"'.format(
+        server_object.cmd()), '"{}"'.format(client_object.cmd()), '0']
+    cmd += server_object.post_checks()
+    cmd += client_object.post_checks()
+    cmd += ['-s "HRR selected_group: {:s}"'.format(server_named_group)]
+    prefix = ' \\\n' + (' '*9)
+    cmd = prefix.join(cmd)
+    return '\n'.join(server_object.pre_checks() +
+                     client_object.pre_checks() +
+                     [cmd])
 
 SSL_OUTPUT_HEADER = '''#!/bin/sh
 
@@ -491,6 +772,16 @@
                                        cipher=cipher, named_group=named_group,
                                        sig_alg=sig_alg)
 
+        for client, server, cipher, named_group, sig_alg in \
+            itertools.product(SERVER_CLIENT_CLASSES.keys(),
+                              SERVER_SERVER_CLASSES.keys(),
+                              CIPHER_SUITE_IANA_VALUE.keys(),
+                              NAMED_GROUP_IANA_VALUE.keys(),
+                              SIG_ALG_IANA_VALUE.keys()):
+            yield generate_server_side_compat_test(client=client, server=server,
+                                                   cipher=cipher, named_group=named_group,
+                                                   sig_alg=sig_alg)
+
         # Generate Hello Retry Request  compat test cases
         for client, server, client_named_group, server_named_group in \
             itertools.product(CLIENT_CLASSES.keys(),
@@ -503,6 +794,17 @@
                                                server_named_group=server_named_group,
                                                cert_sig_alg="ecdsa_secp256r1_sha256")
 
+        for client, server, client_named_group, server_named_group in \
+            itertools.product(SERVER_CLIENT_CLASSES.keys(),
+                              SERVER_SERVER_CLASSES.keys(),
+                              NAMED_GROUP_IANA_VALUE.keys(),
+                              NAMED_GROUP_IANA_VALUE.keys()):
+            if client_named_group != server_named_group:
+                yield generate_server_hrr_compat_test(client=client, server=server,
+                                                      client_named_group=client_named_group,
+                                                      server_named_group=server_named_group,
+                                                      cert_sig_alg="ecdsa_secp256r1_sha256")
+
     if args.generate_all_tls13_compat_tests:
         if args.output:
             with open(args.output, 'w', encoding="utf-8") as f:
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 6eaa534..aafe0e0 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -82,6 +82,7 @@
     O_NEXT_SRV="$OPENSSL_NEXT s_server -www -cert data_files/server5.crt -key data_files/server5.key"
     O_NEXT_SRV_NO_CERT="$OPENSSL_NEXT s_server -www "
     O_NEXT_CLI="echo 'GET / HTTP/1.0' | $OPENSSL_NEXT s_client -CAfile data_files/test-ca_cat12.crt"
+    O_NEXT_CLI_NO_CERT="echo 'GET / HTTP/1.0' | $OPENSSL_NEXT s_client"
 else
     O_NEXT_SRV=false
     O_NEXT_SRV_NO_CERT=false
@@ -98,6 +99,7 @@
 
 if [ -n "${GNUTLS_NEXT_CLI:-}" ]; then
     G_NEXT_CLI="echo 'GET / HTTP/1.0' | $GNUTLS_NEXT_CLI --x509cafile data_files/test-ca_cat12.crt"
+    G_NEXT_CLI_NO_CERT="echo 'GET / HTTP/1.0' | $GNUTLS_NEXT_CLI"
 else
     G_NEXT_CLI=false
 fi
@@ -1538,6 +1540,7 @@
 # Note: Using 'localhost' rather than 127.0.0.1 here is unwise, as on many
 # machines that will resolve to ::1, and we don't want ipv6 here.
 P_SRV="$P_SRV server_addr=127.0.0.1 server_port=$SRV_PORT"
+P_SRV_NO_CERT="$P_SRV server_addr=127.0.0.1 server_port=$SRV_PORT"
 P_CLI="$P_CLI server_addr=127.0.0.1 server_port=+SRV_PORT"
 P_PXY="$P_PXY server_addr=127.0.0.1 server_port=$SRV_PORT listen_addr=127.0.0.1 listen_port=$PXY_PORT ${SEED:+"seed=$SEED"}"
 O_SRV="$O_SRV -accept $SRV_PORT"
@@ -1554,6 +1557,7 @@
     O_NEXT_SRV="$O_NEXT_SRV -accept $SRV_PORT"
     O_NEXT_SRV_NO_CERT="$O_NEXT_SRV_NO_CERT -accept $SRV_PORT"
     O_NEXT_CLI="$O_NEXT_CLI -connect 127.0.0.1:+SRV_PORT"
+    O_NEXT_CLI_NO_CERT="$O_NEXT_CLI_NO_CERT -connect 127.0.0.1:+SRV_PORT"
 fi
 
 if [ -n "${GNUTLS_NEXT_SERV:-}" ]; then