diff --git a/README.md b/README.md
index a869daa..3111de0 100644
--- a/README.md
+++ b/README.md
@@ -464,6 +464,18 @@ The high-level API covers operations including:
 
 The generic `invoke()` API remains available for compatible QKMS operations that do not yet have a dedicated facade function.
 
+For MPC-backed key creation, prefer `create_key_async()` when the ceremony can outlive an HTTP proxy/CDN timeout. It sends the QKMS-compatible `CreateKey` request with the signed `?async=1` query so QKMS can acknowledge the task immediately while DKG continues asynchronously:
+
+```cpp
+const auto created = quilibrium::sync_wait(
+    sdk->kms().create_key_async(
+        R"({"KeySpec":"ECC_SECG_P256K1","KeyUsage":"SIGN_VERIFY"})"
+    )
+);
+```
+
+This SDK intentionally covers the signed QKMS HTTP/KMS surface. The QNZM login flow and participant-side MPC sidecar/ceremony orchestration are a separate concern; applications that need browser/server sidecars participating in DKG should use the official Quilibrium QKMS SDK for that layer.
+
 ---
 
 # Native Quilibrium Protocol
diff --git a/docs/SERVICE_MATRIX.md b/docs/SERVICE_MATRIX.md
index f872553..48fe11e 100644
--- a/docs/SERVICE_MATRIX.md
+++ b/docs/SERVICE_MATRIX.md
@@ -6,7 +6,7 @@
 | HyperSnap casts | `quilibrium.sdk`, `quilibrium.hypersnap` | Typed get/search, conversation JSON + raw API | Farcaster writes use signed protocol messages |
 | HyperSnap feeds | `quilibrium.sdk`, `quilibrium.hypersnap` | Following/trending/user-casts typed pages | Additional documented paths remain available through raw GET |
 | QStorage | `quilibrium.sdk`, `quilibrium.qstorage` | Header SigV4, presigned PUT/GET/HEAD URLs, signed-header contracts, bucket/object common ops, copy/head/list, multipart create/upload/complete/abort/list, raw execute/presign | XML is returned raw; full presigned multipart orchestration can build on generic arbitrary-target presigning |
-| QKMS | `quilibrium.sdk`, `quilibrium.qkms` | SigV4 generic invoke + named key/crypto/data-key/MAC/import/policy/alias/grant/tag/rotation/replication/deletion methods | QNZM/MPC sidecar login/session workflow is separate from the KMS-compatible API |
+| QKMS | `quilibrium.sdk`, `quilibrium.qkms` | SigV4 generic invoke + named key/crypto/data-key/MAC/import/policy/alias/grant/tag/rotation/replication/deletion methods + async `CreateKey` (`?async=1`) | QNZM/MPC sidecar login/session and participant ceremony workflow are separate from the KMS-compatible API |
 | NodeService | `quilibrium.sdk`, `quilibrium.protocol` | Unary raw-protobuf call + complete registry | Typed generated protobuf wrapper not bundled |
 | ConnectivityService | same | Unary raw-protobuf + registry | — |
 | GlobalService | same | Unary methods callable; stream method registered | Server streaming execution not implemented in v1.1 |
diff --git a/src/qkms.cpp b/src/qkms.cpp
index 16bd8e1..61eae77 100644
--- a/src/qkms.cpp
+++ b/src/qkms.cpp
@@ -27,15 +27,16 @@ client::~client()=default;
 client::client(client&&) noexcept=default;
 client& client::operator=(client&&) noexcept=default;
 
-task<result<response>> client::invoke(std::string operation,bytes payload,call_options options) {
+task<result<response>> client::invoke(std::string operation,bytes payload,call_options options,std::string query) {
     if(!impl_->transport) co_return std::unexpected(error{.domain=error_domain::configuration,.code=400,.message="HTTP transport is not configured"});
     if(impl_->endpoints.empty()) co_return std::unexpected(error{.domain=error_domain::configuration,.code=401,.message="QKMS endpoint list is empty"});
 
     const auto attempts = std::max<std::uint32_t>(1U, options.max_attempts);
     error last_error{.domain=error_domain::transport,.code=402,.message="QKMS request failed",.retryable=true};
+    const std::string target=query.empty()?"/":"/?"+query;
     for(std::uint32_t attempt=0; attempt<attempts; ++attempt) {
         const auto& selected=impl_->endpoints[attempt % impl_->endpoints.size()];
-        http_request request{.verb=http_method::post,.target_endpoint=selected,.target="/",.header_fields={{"content-type","application/x-amz-json-1.1"},{"x-amz-target",impl_->target_prefix+"."+operation}},.body=payload};
+        http_request request{.verb=http_method::post,.target_endpoint=selected,.target=target,.header_fields={{"content-type","application/json"},{"x-amz-target",impl_->target_prefix+"."+operation}},.body=payload};
         if(auto status=impl_->signer.sign(request);!status) co_return std::unexpected(status.error());
         auto raw=impl_->transport->send_now(std::move(request),options);
         if(!raw) {
@@ -53,7 +54,8 @@ task<result<response>> client::invoke(std::string operation,bytes payload,call_o
 }
 
 #define QL_KMS_FORWARD(name,operation) task<result<response>> client::name(bytes p,call_options o){co_return sync_wait(invoke(operation,std::move(p),o));}
-QL_KMS_FORWARD(create_key,"CreateKey")
+task<result<response>> client::create_key(bytes p,call_options o){o.idempotent=false;co_return sync_wait(invoke("CreateKey",std::move(p),o));}
+task<result<response>> client::create_key_async(bytes p,call_options o){o.idempotent=false;co_return sync_wait(invoke("CreateKey",std::move(p),o,"async=1"));}
 QL_KMS_FORWARD(describe_key,"DescribeKey")
 QL_KMS_FORWARD(enable_key,"EnableKey")
 QL_KMS_FORWARD(disable_key,"DisableKey")
diff --git a/src/qkms.cppm b/src/qkms.cppm
index 409cd71..bc2f8cb 100644
--- a/src/qkms.cppm
+++ b/src/qkms.cppm
@@ -15,8 +15,12 @@ class client final {
 public:
     client(config configuration, http_transport_ptr transport);
     ~client(); client(client&&) noexcept; client& operator=(client&&) noexcept; client(const client&)=delete; client& operator=(const client&)=delete;
-    [[nodiscard]] task<result<response>> invoke(std::string operation, bytes json_payload, call_options options = {});
+    /** Invokes a QKMS operation. `query` is the raw query string without a leading `?` and is included in SigV4 canonicalization. */
+    [[nodiscard]] task<result<response>> invoke(std::string operation, bytes json_payload, call_options options = {}, std::string query = {});
+    /** Blocking CreateKey; waits for QKMS to complete the MPC operation. */
     [[nodiscard]] task<result<response>> create_key(bytes payload, call_options options = {});
+    /** Non-blocking CreateKey (`?async=1`); avoids proxy/CDN 504s while MPC/DKG continues asynchronously. */
+    [[nodiscard]] task<result<response>> create_key_async(bytes payload, call_options options = {});
     [[nodiscard]] task<result<response>> describe_key(bytes payload, call_options options = {});
     [[nodiscard]] task<result<response>> list_keys(bytes payload = {}, call_options options = {});
     [[nodiscard]] task<result<response>> enable_key(bytes payload, call_options options = {});
diff --git a/src/sdk_facade.cpp b/src/sdk_facade.cpp
index 26daa8b..09a20a0 100644
--- a/src/sdk_facade.cpp
+++ b/src/sdk_facade.cpp
@@ -636,13 +636,32 @@ task<result<service_response>> kms_api::invoke(std::string operation,std::string
     if (!state) co_return std::unexpected(error{.domain=error_domain::configuration,.code=850,.message="SDK state is unavailable"});
     auto view=as_bytes(json_payload);
     bytes payload(view.begin(),view.end());
-    auto response=send_with_failover(*state,state->kms,http_method::post,"/",{{"content-type","application/x-amz-json-1.1"},{"x-amz-target","TrentService."+operation}},std::move(payload),options,&state->kms_credentials,state->kms_region,"kms");
+    auto response=send_with_failover(*state,state->kms,http_method::post,"/",{{"content-type","application/json"},{"x-amz-target","TrentService."+operation}},std::move(payload),options,&state->kms_credentials,state->kms_region,"kms");
     if (!response) co_return std::unexpected(response.error());
     co_return convert(std::move(*response));
 }
 
 #define QL_SDK_KMS_FORWARD(name,operation) task<result<service_response>> kms_api::name(std::string payload,call_options options) const { co_return sync_wait(invoke(operation,std::move(payload),options)); }
-QL_SDK_KMS_FORWARD(create_key,"CreateKey")
+task<result<service_response>> kms_api::create_key(std::string json_payload,call_options options) const {
+    auto* state=state_cast(state_);
+    if (!state) co_return std::unexpected(error{.domain=error_domain::configuration,.code=850,.message="SDK state is unavailable"});
+    options.idempotent=false;
+    auto view=as_bytes(json_payload);
+    bytes payload(view.begin(),view.end());
+    auto response=send_with_failover(*state,state->kms,http_method::post,"/",{{"content-type","application/json"},{"x-amz-target","TrentService.CreateKey"}},std::move(payload),options,&state->kms_credentials,state->kms_region,"kms");
+    if (!response) co_return std::unexpected(response.error());
+    co_return convert(std::move(*response));
+}
+task<result<service_response>> kms_api::create_key_async(std::string json_payload,call_options options) const {
+    auto* state=state_cast(state_);
+    if (!state) co_return std::unexpected(error{.domain=error_domain::configuration,.code=850,.message="SDK state is unavailable"});
+    options.idempotent=false;
+    auto view=as_bytes(json_payload);
+    bytes payload(view.begin(),view.end());
+    auto response=send_with_failover(*state,state->kms,http_method::post,"/?async=1",{{"content-type","application/json"},{"x-amz-target","TrentService.CreateKey"}},std::move(payload),options,&state->kms_credentials,state->kms_region,"kms");
+    if (!response) co_return std::unexpected(response.error());
+    co_return convert(std::move(*response));
+}
 QL_SDK_KMS_FORWARD(describe_key,"DescribeKey")
 QL_SDK_KMS_FORWARD(encrypt,"Encrypt")
 QL_SDK_KMS_FORWARD(decrypt,"Decrypt")
diff --git a/src/sdk_facade.cppm b/src/sdk_facade.cppm
index caf89c9..5bfb3e0 100644
--- a/src/sdk_facade.cppm
+++ b/src/sdk_facade.cppm
@@ -195,6 +195,8 @@ public:
     /** Invokes any compatible `TrentService.<operation>` QKMS operation. */
     [[nodiscard]] task<result<service_response>> invoke(std::string operation,std::string json_payload="{}",call_options options={}) const;
     [[nodiscard]] task<result<service_response>> create_key(std::string json_payload="{}",call_options options={}) const;
+    /** Non-blocking CreateKey (`?async=1`) for MPC/DKG operations that may outlive proxy timeouts. */
+    [[nodiscard]] task<result<service_response>> create_key_async(std::string json_payload="{}",call_options options={}) const;
     [[nodiscard]] task<result<service_response>> describe_key(std::string json_payload,call_options options={}) const;
     [[nodiscard]] task<result<service_response>> encrypt(std::string json_payload,call_options options={}) const;
     [[nodiscard]] task<result<service_response>> decrypt(std::string json_payload,call_options options={}) const;
diff --git a/tests/c_api_tests.c b/tests/c_api_tests.c
index a7eaf39..c8732b1 100644
--- a/tests/c_api_tests.c
+++ b/tests/c_api_tests.c
@@ -3,7 +3,7 @@
 #include <string.h>
 
 int main(void) {
-    assert(strcmp(ql_version(),"1.1.0")==0);
+    assert(strcmp(ql_version(),"1.2.0")==0);
     ql_error error={0};
     ql_sdk* sdk=ql_sdk_create(NULL,&error);
     assert(sdk!=NULL);
diff --git a/tests/facade_tests.cpp b/tests/facade_tests.cpp
index bdb8619..bd972ff 100644
--- a/tests/facade_tests.cpp
+++ b/tests/facade_tests.cpp
@@ -9,10 +9,13 @@ import quilibrium.sdk;
 struct mock_state final {
     bool saw_storage_auth{false};
     bool saw_kms_auth{false};
+    bool saw_kms_async_create{false};
+    bool saw_kms_json_content_type{false};
+    bool saw_kms_create_non_idempotent{false};
     bool saw_native_grpc{false};
 };
 
-quilibrium::result<quilibrium::http_response> mock_send(void* opaque,quilibrium::http_request request,quilibrium::call_options) {
+quilibrium::result<quilibrium::http_response> mock_send(void* opaque,quilibrium::http_request request,quilibrium::call_options options) {
     auto* state=static_cast<mock_state*>(opaque);
     std::string body;
     quilibrium::http_headers headers{{"content-type","application/json"}};
@@ -24,8 +27,13 @@ quilibrium::result<quilibrium::http_response> mock_send(void* opaque,quilibrium:
     } else if(request.target=="/bucket/object.bin") {
         state->saw_storage_auth=request.header_fields.contains("authorization");
         body="storage-ok";
-    } else if(request.target=="/"&&request.header_fields.contains("x-amz-target")) {
+    } else if((request.target=="/"||request.target=="/?async=1")&&request.header_fields.contains("x-amz-target")) {
         state->saw_kms_auth=request.header_fields.contains("authorization");
+        if(request.header_fields.at("x-amz-target")=="TrentService.CreateKey") {
+            if(request.target=="/?async=1") state->saw_kms_async_create=true;
+            if(!options.idempotent) state->saw_kms_create_non_idempotent=true;
+        }
+        if(const auto ct=request.header_fields.find("content-type");ct!=request.header_fields.end()&&ct->second=="application/json") state->saw_kms_json_content_type=true;
         body=R"({"Signature":"AA=="})";
     } else if(request.target=="/quilibrium.node.node.pb.NodeService/GetNodeInfo") {
         state->saw_native_grpc=true;
@@ -63,6 +71,10 @@ int main(){
 
     auto signed_value=quilibrium::sync_wait(q->kms().invoke("Sign",R"({"KeyId":"test"})"));
     assert(signed_value&&signed_value->status_code==200&&state->saw_kms_auth);
+    auto blocking_key=quilibrium::sync_wait(q->kms().create_key(R"({"KeySpec":"ECC_SECG_P256K1"})"));
+    assert(blocking_key&&blocking_key->status_code==200&&state->saw_kms_create_non_idempotent);
+    auto async_key=quilibrium::sync_wait(q->kms().create_key_async(R"({"KeySpec":"ECC_SECG_P256K1"})"));
+    assert(async_key&&async_key->status_code==200&&state->saw_kms_async_create&&state->saw_kms_json_content_type&&state->saw_kms_create_non_idempotent);
 
     auto node_info=quilibrium::sync_wait(q->native().call(quilibrium::native_service::node,"GetNodeInfo",{}));
     assert(node_info&&node_info->size()==2&&state->saw_native_grpc);
diff --git a/tests/service_tests.cpp b/tests/service_tests.cpp
index eb61ef6..d4582bd 100644
--- a/tests/service_tests.cpp
+++ b/tests/service_tests.cpp
@@ -15,15 +15,23 @@ struct mock_state final {
     bool saw_kms_target{false};
     bool saw_multipart{false};
     bool saw_rotation_target{false};
+    bool saw_async_create{false};
+    bool saw_qkms_json_content_type{false};
+    bool saw_create_non_idempotent{false};
 };
 
-quilibrium::result<quilibrium::http_response> service_send(void* opaque,quilibrium::http_request request,quilibrium::call_options) {
+quilibrium::result<quilibrium::http_response> service_send(void* opaque,quilibrium::http_request request,quilibrium::call_options options) {
     auto* state=static_cast<mock_state*>(opaque);
     if (request.header_fields.contains("authorization")) state->saw_authorization=true;
     if (request.target.find("?uploads") != std::string::npos) state->saw_multipart=true;
     if (const auto it=request.header_fields.find("x-amz-target");it!=request.header_fields.end()) {
         if (it->second=="TrentService.Sign") state->saw_kms_target=true;
         if (it->second=="TrentService.EnableKeyRotation") state->saw_rotation_target=true;
+        if (it->second=="TrentService.CreateKey") {
+            if (request.target=="/?async=1") state->saw_async_create=true;
+            if (!options.idempotent) state->saw_create_non_idempotent=true;
+        }
+        if (const auto ct=request.header_fields.find("content-type");ct!=request.header_fields.end() && ct->second=="application/json") state->saw_qkms_json_content_type=true;
     }
     std::string body=request.target.starts_with("/v2/farcaster/user")?R"({"user":{"fid":3,"username":"dwr.eth"}})":"{}";
     const auto view=quilibrium::as_bytes(body);
@@ -66,8 +74,15 @@ int main() {
         assert(response&&response->status_code==200);
         auto rotation=quilibrium::sync_wait(client.enable_key_rotation({}));
         assert(rotation&&rotation->status_code==200);
+        auto blocking_create=quilibrium::sync_wait(client.create_key({}));
+        assert(blocking_create&&blocking_create->status_code==200);
+        auto async_create=quilibrium::sync_wait(client.create_key_async({}));
+        assert(async_create&&async_create->status_code==200);
         assert(state->saw_kms_target);
         assert(state->saw_rotation_target);
+        assert(state->saw_async_create);
+        assert(state->saw_qkms_json_content_type);
+        assert(state->saw_create_non_idempotent);
     }
 
     {