diff --git a/examples/arduino/z_get.ino b/examples/arduino/z_get.ino
index bd9ab841f..9df8af2f8 100644
--- a/examples/arduino/z_get.ino
+++ b/examples/arduino/z_get.ino
@@ -111,7 +111,8 @@ void loop() {
     Serial.print("Sending Query ");
     Serial.print(KEYEXPR);
     Serial.println(" ...");
-    z_get_options_t opts = z_get_options_default();
+    z_get_options_t opts;
+    z_get_options_default(&opts);
     if (strcmp(VALUE, "") != 0) {
         opts.value.payload = _z_bytes_wrap((const uint8_t *)VALUE, strlen(VALUE));
     }
diff --git a/examples/espidf/z_get.c b/examples/espidf/z_get.c
index cd69bc600..180de1d61 100644
--- a/examples/espidf/z_get.c
+++ b/examples/espidf/z_get.c
@@ -156,7 +156,8 @@ void app_main() {
     while (1) {
         sleep(5);
         printf("Sending Query '%s'...\n", KEYEXPR);
-        z_get_options_t opts = z_get_options_default();
+        z_get_options_t opts;
+        z_get_options_default(&opts);
         if (strcmp(VALUE, "") != 0) {
             opts.value.payload = _z_bytes_wrap((const uint8_t *)VALUE, strlen(VALUE));
         }
diff --git a/examples/freertos_plus_tcp/z_get.c b/examples/freertos_plus_tcp/z_get.c
index 97c49dd79..c3473901e 100644
--- a/examples/freertos_plus_tcp/z_get.c
+++ b/examples/freertos_plus_tcp/z_get.c
@@ -80,7 +80,8 @@ void app_main(void) {
     while (1) {
         z_sleep_s(5);
         printf("Sending Query '%s'...\n", KEYEXPR);
-        z_get_options_t opts = z_get_options_default();
+        z_get_options_t opts;
+        z_get_options_default(&opts);
         if (strcmp(VALUE, "") != 0) {
             opts.value.payload = _z_bytes_wrap((const uint8_t *)VALUE, strlen(VALUE));
         }
diff --git a/examples/freertos_plus_tcp/z_queryable.c b/examples/freertos_plus_tcp/z_queryable.c
index c962f5107..edf173db2 100644
--- a/examples/freertos_plus_tcp/z_queryable.c
+++ b/examples/freertos_plus_tcp/z_queryable.c
@@ -39,7 +39,8 @@ void query_handler(const z_query_t *query, void *ctx) {
     if (payload_value.payload.len > 0) {
         printf("     with value '%.*s'\n", (int)payload_value.payload.len, payload_value.payload.start);
     }
-    z_query_reply_options_t options = z_query_reply_options_default();
+    z_query_reply_options_t options;
+    z_query_reply_options_default(&options);
     options.encoding = z_encoding(Z_ENCODING_PREFIX_TEXT_PLAIN, NULL);
     z_query_reply(query, z_keyexpr(KEYEXPR), (const unsigned char *)VALUE, strlen(VALUE), &options);
     z_drop(z_move(keystr));
diff --git a/examples/mbed/z_get.cpp b/examples/mbed/z_get.cpp
index f88d4224b..9bf56cdcd 100644
--- a/examples/mbed/z_get.cpp
+++ b/examples/mbed/z_get.cpp
@@ -76,7 +76,8 @@ int main(int argc, char **argv) {
     while (1) {
         z_sleep_s(5);
         printf("Sending Query '%s'...\n", KEYEXPR);
-        z_get_options_t opts = z_get_options_default();
+        z_get_options_t opts;
+        z_get_options_default(&opts);
         if (strcmp(VALUE, "") != 0) {
             opts.value.payload = _z_bytes_wrap((const uint8_t *)VALUE, strlen(VALUE));
         }
diff --git a/examples/unix/c11/z_get.c b/examples/unix/c11/z_get.c
index 27bc5631b..42fbb1a92 100644
--- a/examples/unix/c11/z_get.c
+++ b/examples/unix/c11/z_get.c
@@ -128,7 +128,8 @@ int main(int argc, char **argv) {
 
     z_mutex_lock(&mutex);
     printf("Sending Query '%s'...\n", keyexpr);
-    z_get_options_t opts = z_get_options_default();
+    z_get_options_t opts;
+    z_get_options_default(&opts);
     if (value != NULL) {
         opts.value.payload = _z_bytes_wrap((const uint8_t *)value, strlen(value));
     }
diff --git a/examples/unix/c11/z_get_channel.c b/examples/unix/c11/z_get_channel.c
index e1de0b0da..2ad10ba85 100644
--- a/examples/unix/c11/z_get_channel.c
+++ b/examples/unix/c11/z_get_channel.c
@@ -88,7 +88,8 @@ int main(int argc, char **argv) {
     }
 
     printf("Sending Query '%s'...\n", keyexpr);
-    z_get_options_t opts = z_get_options_default();
+    z_get_options_t opts;
+    z_get_options_default(&opts);
     if (value != NULL) {
         opts.value.payload = _z_bytes_wrap((const uint8_t *)value, strlen(value));
     }
diff --git a/examples/unix/c11/z_queryable.c b/examples/unix/c11/z_queryable.c
index 8bfe513ef..8876ddffd 100644
--- a/examples/unix/c11/z_queryable.c
+++ b/examples/unix/c11/z_queryable.c
@@ -49,7 +49,8 @@ void query_handler(const z_query_t *query, void *ctx) {
     }
 #endif
 
-    z_query_reply_options_t options = z_query_reply_options_default();
+    z_query_reply_options_t options;
+    z_query_reply_options_default(&options);
     options.encoding = z_encoding(Z_ENCODING_PREFIX_TEXT_PLAIN, NULL);
 
 #if Z_FEATURE_ATTACHMENT == 1
diff --git a/examples/unix/c11/z_queryable_channel.c b/examples/unix/c11/z_queryable_channel.c
index aff9a9d4c..e568a2b17 100644
--- a/examples/unix/c11/z_queryable_channel.c
+++ b/examples/unix/c11/z_queryable_channel.c
@@ -107,7 +107,8 @@ int main(int argc, char **argv) {
         if (payload_value.payload.len > 0) {
             printf("     with value '%.*s'\n", (int)payload_value.payload.len, payload_value.payload.start);
         }
-        z_query_reply_options_t options = z_query_reply_options_default();
+        z_query_reply_options_t options;
+        z_query_reply_options_default(&options);
         options.encoding = z_encoding(Z_ENCODING_PREFIX_TEXT_PLAIN, NULL);
         z_query_reply(&q, z_keyexpr(keyexpr), (const unsigned char *)value, strlen(value), &options);
         z_drop(z_move(keystr));
diff --git a/examples/unix/c99/z_get.c b/examples/unix/c99/z_get.c
index 8d58fef63..dbfbca469 100644
--- a/examples/unix/c99/z_get.c
+++ b/examples/unix/c99/z_get.c
@@ -114,7 +114,8 @@ int main(int argc, char **argv) {
 
     z_mutex_lock(&mutex);
     printf("Sending Query '%s'...\n", keyexpr);
-    z_get_options_t opts = z_get_options_default();
+    z_get_options_t opts;
+    z_get_options_default(&opts);
     if (value != NULL) {
         opts.value.payload = _z_bytes_wrap((const uint8_t *)value, strlen(value));
     }
diff --git a/examples/unix/c99/z_queryable.c b/examples/unix/c99/z_queryable.c
index 1d28562fc..404a16add 100644
--- a/examples/unix/c99/z_queryable.c
+++ b/examples/unix/c99/z_queryable.c
@@ -28,7 +28,8 @@ void query_handler(const z_query_t *query, void *ctx) {
     z_keyexpr_to_string(z_query_keyexpr(query), &keystr);
     z_bytes_t pred = z_query_parameters(query);
     printf(" >> [Queryable handler] Received Query '%s%.*s'\n", z_str_loan(&keystr), (int)pred.len, pred.start);
-    z_query_reply_options_t options = z_query_reply_options_default();
+    z_query_reply_options_t options;
+    z_query_reply_options_default(&options);
     options.encoding = z_encoding(Z_ENCODING_PREFIX_TEXT_PLAIN, NULL);
     z_query_reply(query, z_keyexpr(keyexpr), (const unsigned char *)value, strlen(value), &options);
     z_str_drop(z_str_move(&keystr));
diff --git a/examples/windows/z_get.c b/examples/windows/z_get.c
index a633fd07b..c7461f60f 100644
--- a/examples/windows/z_get.c
+++ b/examples/windows/z_get.c
@@ -79,7 +79,8 @@ int main(int argc, char **argv) {
 
     z_mutex_lock(&mutex);
     printf("Sending Query '%s'...\n", keyexpr);
-    z_get_options_t opts = z_get_options_default();
+    z_get_options_t opts;
+    z_get_options_default(&opts);
     if (value != NULL) {
         opts.value.payload = _z_bytes_wrap((const uint8_t *)value, strlen(value));
     }
diff --git a/examples/windows/z_queryable.c b/examples/windows/z_queryable.c
index a42bd26cd..f7065ca71 100644
--- a/examples/windows/z_queryable.c
+++ b/examples/windows/z_queryable.c
@@ -31,7 +31,8 @@ void query_handler(const z_query_t *query, void *ctx) {
     if (payload_value.payload.len > 0) {
         printf("     with value '%.*s'\n", (int)payload_value.payload.len, payload_value.payload.start);
     }
-    z_query_reply_options_t options = z_query_reply_options_default();
+    z_query_reply_options_t options;
+    z_query_reply_options_default(&options);
     options.encoding = z_encoding(Z_ENCODING_PREFIX_TEXT_PLAIN, NULL);
     z_query_reply(query, z_keyexpr(keyexpr), (const unsigned char *)value, strlen(value), &options);
     z_drop(z_move(keystr));
diff --git a/examples/zephyr/z_get.c b/examples/zephyr/z_get.c
index 8c0ef5340..cb243a675 100644
--- a/examples/zephyr/z_get.c
+++ b/examples/zephyr/z_get.c
@@ -72,7 +72,8 @@ int main(int argc, char **argv) {
     while (1) {
         sleep(5);
         printf("Sending Query '%s'...\n", KEYEXPR);
-        z_get_options_t opts = z_get_options_default();
+        z_get_options_t opts;
+        z_get_options_default(&opts);
         opts.target = Z_QUERY_TARGET_ALL;
         z_owned_closure_reply_t callback;
         z_closure(&callback, reply_handler, reply_dropper);
diff --git a/include/zenoh-pico/api/primitives.h b/include/zenoh-pico/api/primitives.h
index 456e70160..a47bb6f1a 100644
--- a/include/zenoh-pico/api/primitives.h
+++ b/include/zenoh-pico/api/primitives.h
@@ -1026,7 +1026,7 @@ int8_t z_publisher_delete(const z_publisher_t pub, const z_publisher_delete_opti
  * Returns:
  *   Returns the constructed :c:type:`z_get_options_t`.
  */
-z_get_options_t z_get_options_default(void);
+void z_get_options_default(z_get_options_t *options);
 
 /**
  * Issues a distributed query for a given keyexpr.
@@ -1092,7 +1092,7 @@ z_value_t z_reply_err(const z_owned_reply_t *reply);
  * Returns:
  *   Returns the constructed :c:type:`z_queryable_options_t`.
  */
-z_queryable_options_t z_queryable_options_default(void);
+void z_queryable_options_default(z_queryable_options_t *options);
 
 /**
  * Declares a queryable for the given keyexpr.
@@ -1143,7 +1143,7 @@ int8_t z_undeclare_queryable(z_owned_queryable_t *queryable);
  * Returns:
  *   Returns the constructed :c:type:`z_query_reply_options_t`.
  */
-z_query_reply_options_t z_query_reply_options_default(void);
+void z_query_reply_options_default(z_query_reply_options_t *options);
 
 /**
  * Sends a reply to a query.
@@ -1221,7 +1221,7 @@ int8_t z_undeclare_keyexpr(z_session_t zs, z_owned_keyexpr_t *keyexpr);
  * Returns:
  *   Returns the constructed :c:type:`z_subscriber_options_t`.
  */
-z_subscriber_options_t z_subscriber_options_default(void);
+void z_subscriber_options_default(z_subscriber_options_t *options);
 
 /**
  * Declares a (push) subscriber for the given keyexpr.
diff --git a/src/api/api.c b/src/api/api.c
index eccfe37b2..7410bc563 100644
--- a/src/api/api.c
+++ b/src/api/api.c
@@ -805,15 +805,15 @@ z_owned_keyexpr_t z_publisher_keyexpr(z_publisher_t publisher) {
 #if Z_FEATURE_QUERY == 1
 OWNED_FUNCTIONS_PTR_INTERNAL(z_reply_t, z_owned_reply_t, reply, _z_reply_free, _z_owner_noop_copy)
 
-z_get_options_t z_get_options_default(void) {
-    return (z_get_options_t) {
-        .target = z_query_target_default(), .consolidation = z_query_consolidation_default(),
-        .value = {.encoding = z_encoding_default(), .payload = _z_bytes_empty()},
+void z_get_options_default(z_get_options_t *options) {
+    options->target = z_query_target_default();
+    options->consolidation = z_query_consolidation_default();
+    options->value.encoding = z_encoding_default();
+    options->value.payload = _z_bytes_empty();
 #if Z_FEATURE_ATTACHMENT == 1
-        .attachment = z_attachment_null(),
+    options->attachment = z_attachment_null();
 #endif
-        .timeout_ms = Z_GET_TIMEOUT_DEFAULT
-    };
+    options->timeout_ms = Z_GET_TIMEOUT_DEFAULT;
 }
 
 typedef struct __z_reply_handler_wrapper_t {
@@ -835,7 +835,8 @@ int8_t z_get(z_session_t zs, z_keyexpr_t keyexpr, const char *parameters, z_owne
     void *ctx = callback->context;
     callback->context = NULL;
 
-    z_get_options_t opt = z_get_options_default();
+    z_get_options_t opt;
+    z_get_options_default(&opt);
     if (options != NULL) {
         opt.consolidation = options->consolidation;
         opt.target = options->target;
@@ -894,9 +895,7 @@ OWNED_FUNCTIONS_PTR_COMMON(z_queryable_t, z_owned_queryable_t, queryable)
 OWNED_FUNCTIONS_PTR_CLONE(z_queryable_t, z_owned_queryable_t, queryable, _z_owner_noop_copy)
 void z_queryable_drop(z_owned_queryable_t *val) { z_undeclare_queryable(val); }
 
-z_queryable_options_t z_queryable_options_default(void) {
-    return (z_queryable_options_t){.complete = _Z_QUERYABLE_COMPLETE_DEFAULT};
-}
+void z_queryable_options_default(z_queryable_options_t *options) { options->complete = _Z_QUERYABLE_COMPLETE_DEFAULT; }
 
 z_owned_queryable_t z_declare_queryable(z_session_t zs, z_keyexpr_t keyexpr, z_owned_closure_query_t *callback,
                                         const z_queryable_options_t *options) {
@@ -916,7 +915,8 @@ z_owned_queryable_t z_declare_queryable(z_session_t zs, z_keyexpr_t keyexpr, z_o
         }
     }
 
-    z_queryable_options_t opt = z_queryable_options_default();
+    z_queryable_options_t opt;
+    z_queryable_options_default(&opt);
     if (options != NULL) {
         opt.complete = options->complete;
     }
@@ -933,13 +933,16 @@ int8_t z_undeclare_queryable(z_owned_queryable_t *queryable) {
     return ret;
 }
 
-z_query_reply_options_t z_query_reply_options_default(void) {
-    return (z_query_reply_options_t){.encoding = z_encoding_default()};
-}
+void z_query_reply_options_default(z_query_reply_options_t *options) { options->encoding = z_encoding_default(); }
 
 int8_t z_query_reply(const z_query_t *query, const z_keyexpr_t keyexpr, const uint8_t *payload, size_t payload_len,
                      const z_query_reply_options_t *options) {
-    z_query_reply_options_t opts = options == NULL ? z_query_reply_options_default() : *options;
+    z_query_reply_options_t opts;
+    if (options == NULL) {
+        z_query_reply_options_default(&opts);
+    } else {
+        opts = *options;
+    }
     _z_value_t value = {.payload =
                             {
                                 .start = payload,
@@ -989,9 +992,7 @@ OWNED_FUNCTIONS_PTR_COMMON(z_subscriber_t, z_owned_subscriber_t, subscriber)
 OWNED_FUNCTIONS_PTR_CLONE(z_subscriber_t, z_owned_subscriber_t, subscriber, _z_owner_noop_copy)
 void z_subscriber_drop(z_owned_subscriber_t *val) { z_undeclare_subscriber(val); }
 
-z_subscriber_options_t z_subscriber_options_default(void) {
-    return (z_subscriber_options_t){.reliability = Z_RELIABILITY_DEFAULT};
-}
+void z_subscriber_options_default(z_subscriber_options_t *options) { options->reliability = Z_RELIABILITY_DEFAULT; }
 
 int8_t z_declare_subscriber(z_owned_subscriber_t *sub, z_session_t zs, z_keyexpr_t keyexpr,
                             z_owned_closure_sample_t *callback, const z_subscriber_options_t *options) {
diff --git a/tests/z_api_alignment_test.c b/tests/z_api_alignment_test.c
index 0e490ba62..6ff3bd7c1 100644
--- a/tests/z_api_alignment_test.c
+++ b/tests/z_api_alignment_test.c
@@ -77,7 +77,8 @@ void query_handler(const z_query_t *query, void *arg) {
     (void)(pred);
     z_value_t payload_value = z_query_value(query);
     (void)(payload_value);
-    z_query_reply_options_t _ret_qreply_opt = z_query_reply_options_default();
+    z_query_reply_options_t _ret_qreply_opt;
+    z_query_reply_options_default(&_ret_qreply_opt);
     z_query_reply(query, z_keyexpr(z_loan(k_str)), (const uint8_t *)value, strlen(value), &_ret_qreply_opt);
 
     z_drop(z_move(k_str));
@@ -287,7 +288,8 @@ int main(int argc, char **argv) {
     printf("Declaring Subscriber...");
     z_owned_closure_sample_t _ret_closure_sample;
     z_closure(&_ret_closure_sample, data_handler, NULL, &ls1);
-    z_subscriber_options_t _ret_sub_opt = z_subscriber_options_default();
+    z_subscriber_options_t _ret_sub_opt;
+    z_subscriber_options_default(&_ret_sub_opt);
     z_owned_subscriber_t _ret_sub;
     _ret_int8 =
         z_declare_subscriber(&_ret_sub, z_loan(s2), z_keyexpr(keyexpr_str), z_move(_ret_closure_sample), &_ret_sub_opt);
@@ -304,7 +306,8 @@ int main(int argc, char **argv) {
     printf("Ok\n");
 
     printf("Session Put...");
-    z_put_options_t _ret_put_opt = z_put_options_default();
+    z_put_options_t _ret_put_opt;
+    z_put_options_default(&_ret_put_opt);
     _ret_put_opt.congestion_control = Z_CONGESTION_CONTROL_BLOCK;
     z_encoding_t _ret_encoding = z_encoding_default();
     (void)(_ret_encoding);
@@ -385,7 +388,8 @@ int main(int argc, char **argv) {
     printf("Declaring Queryable...");
     z_owned_closure_query_t _ret_closure_query;
     z_closure(&_ret_closure_query, query_handler, NULL, &ls1);
-    z_queryable_options_t _ret_qle_opt = z_queryable_options_default();
+    z_queryable_options_t _ret_qle_opt;
+    z_queryable_options_default(&_ret_qle_opt);
     z_owned_queryable_t qle =
         z_declare_queryable(z_loan(s1), z_keyexpr(s1_res), z_move(_ret_closure_query), &_ret_qle_opt);
     assert(z_check(qle));
@@ -397,7 +401,8 @@ int main(int argc, char **argv) {
     z_session_t ls2 = z_loan(s2);
     z_owned_closure_reply_t _ret_closure_reply;
     z_closure(&_ret_closure_reply, reply_handler, NULL, &ls2);
-    z_get_options_t _ret_get_opt = z_get_options_default();
+    z_get_options_t _ret_get_opt;
+    z_get_options_default(&_ret_get_opt);
     _ret_get_opt.target = z_query_target_default();
     _ret_get_opt.consolidation = z_query_consolidation_auto();
     (void)(_ret_get_opt.consolidation);