diff --git a/build-scripts/config_common.cmake b/build-scripts/config_common.cmake
index d89c3a285e..366abb16ab 100644
--- a/build-scripts/config_common.cmake
+++ b/build-scripts/config_common.cmake
@@ -546,7 +546,8 @@ if (WAMR_BUILD_WASI_NN EQUAL 1)
   # Variant backends
   if (NOT WAMR_BUILD_WASI_NN_TFLITE EQUAL 1 AND
       NOT WAMR_BUILD_WASI_NN_OPENVINO EQUAL 1 AND
-      NOT WAMR_BUILD_WASI_NN_LLAMACPP EQUAL 1)
+      NOT WAMR_BUILD_WASI_NN_LLAMACPP EQUAL 1 AND
+      NOT WAMR_BUILD_WASI_NN_ONNX EQUAL 1)
     message (FATAL_ERROR "   Need to select a backend for WASI-NN")
   endif ()
 
@@ -562,6 +563,10 @@ if (WAMR_BUILD_WASI_NN EQUAL 1)
     message ("     WASI-NN: backend llamacpp enabled")
     add_definitions (-DWASM_ENABLE_WASI_NN_LLAMACPP)
   endif ()
+  if (WAMR_BUILD_WASI_NN_ONNX EQUAL 1)
+    message ("     WASI-NN: backend onnx enabled")
+    add_definitions (-DWASM_ENABLE_WASI_NN_ONNX)
+  endif ()
   # Variant devices
   if (WAMR_BUILD_WASI_NN_ENABLE_GPU EQUAL 1)
       message ("     WASI-NN: GPU enabled")
diff --git a/core/iwasm/libraries/wasi-nn/README.md b/core/iwasm/libraries/wasi-nn/README.md
index 2e926a0327..e16891a1ba 100644
--- a/core/iwasm/libraries/wasi-nn/README.md
+++ b/core/iwasm/libraries/wasi-nn/README.md
@@ -26,6 +26,7 @@ $ cmake -DWAMR_BUILD_WASI_NN=1 <other options> ...
 - `WAMR_BUILD_WASI_NN_TFLITE`. This option designates TensorFlow Lite as the backend.
 - `WAMR_BUILD_WASI_NN_OPENVINO`. This option designates OpenVINO as the backend.
 - `WAMR_BUILD_WASI_NN_LLAMACPP`. This option designates Llama.cpp as the backend.
+- `WAMR_BUILD_WASI_NN_ONNX`. This option designates ONNX Runtime as the backend.
 
 ### Wasm
 
@@ -151,7 +152,7 @@ docker run \
 
 Supported:
 
-- Graph encoding: `tensorflowlite`, `openvino` and `ggml`
+- Graph encoding: `tensorflowlite`, `openvino`, `ggml` and `onnx`
 - Execution target: `cpu` for all. `gpu` and `tpu` for `tensorflowlite`.
 - Tensor type: `fp32`.
 
diff --git a/core/iwasm/libraries/wasi-nn/cmake/Findonnxruntime.cmake b/core/iwasm/libraries/wasi-nn/cmake/Findonnxruntime.cmake
new file mode 100644
index 0000000000..db8f287e36
--- /dev/null
+++ b/core/iwasm/libraries/wasi-nn/cmake/Findonnxruntime.cmake
@@ -0,0 +1,86 @@
+# Copyright 2025 Sony Semiconductor Solutions Corporation.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+# Find ONNX Runtime library
+#
+# This module defines the following variables:
+#
+# ::
+#
+#   onnxruntime_FOUND        - True if onnxruntime is found
+#   onnxruntime_INCLUDE_DIRS - Include directories for onnxruntime
+#   onnxruntime_LIBRARIES    - List of libraries for onnxruntime
+#   onnxruntime_VERSION      - Version of onnxruntime
+#
+# ::
+#
+# Example usage:
+#
+#   find_package(onnxruntime)
+#   if(onnxruntime_FOUND)
+#     target_link_libraries(app onnxruntime)
+#   endif()
+
+# First try to find ONNX Runtime using the CMake config file
+# FIXME: This is a temporary workaround for ONNX Runtime's broken CMake config on Linux.
+# See https://github.com/microsoft/onnxruntime/issues/25279
+# Once the upstream issue is fixed, this conditional can be safely removed.
+if(NOT CMAKE_SYSTEM_NAME STREQUAL "Linux")
+  find_package(onnxruntime CONFIG QUIET)
+  if(onnxruntime_FOUND)
+    return()
+  endif()
+endif()
+
+# If not found via CMake config, try to find manually
+find_path(onnxruntime_INCLUDE_DIR
+  NAMES onnxruntime_c_api.h
+  PATHS
+    /usr/include
+    /usr/local/include
+    /opt/onnxruntime/include
+    $ENV{ONNXRUNTIME_ROOT}/include
+    ${CMAKE_CURRENT_LIST_DIR}/../../../../..
+)
+
+find_library(onnxruntime_LIBRARY
+  NAMES onnxruntime
+  PATHS
+    /usr/lib
+    /usr/local/lib
+    /opt/onnxruntime/lib
+    $ENV{ONNXRUNTIME_ROOT}/lib
+    ${CMAKE_CURRENT_LIST_DIR}/../../../../..
+)
+
+# Try to determine version from header file
+if(onnxruntime_INCLUDE_DIR)
+  file(STRINGS "${onnxruntime_INCLUDE_DIR}/onnxruntime_c_api.h" onnxruntime_version_str
+    REGEX "^#define[\t ]+ORT_API_VERSION[\t ]+[0-9]+")
+  
+  if(onnxruntime_version_str)
+    string(REGEX REPLACE "^#define[\t ]+ORT_API_VERSION[\t ]+([0-9]+)" "\\1"
+      onnxruntime_VERSION "${onnxruntime_version_str}")
+  endif()
+endif()
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(onnxruntime
+  REQUIRED_VARS onnxruntime_LIBRARY onnxruntime_INCLUDE_DIR
+  VERSION_VAR onnxruntime_VERSION
+)
+
+if(onnxruntime_FOUND)
+  set(onnxruntime_LIBRARIES ${onnxruntime_LIBRARY})
+  set(onnxruntime_INCLUDE_DIRS ${onnxruntime_INCLUDE_DIR})
+
+  if(NOT TARGET onnxruntime::onnxruntime)
+    add_library(onnxruntime::onnxruntime UNKNOWN IMPORTED)
+    set_target_properties(onnxruntime::onnxruntime PROPERTIES
+      IMPORTED_LOCATION "${onnxruntime_LIBRARY}"
+      INTERFACE_INCLUDE_DIRECTORIES "${onnxruntime_INCLUDE_DIRS}"
+    )
+  endif()
+endif()
+
+mark_as_advanced(onnxruntime_INCLUDE_DIR onnxruntime_LIBRARY)
diff --git a/core/iwasm/libraries/wasi-nn/cmake/wasi_nn.cmake b/core/iwasm/libraries/wasi-nn/cmake/wasi_nn.cmake
index b771b1c402..56a7b44e4a 100644
--- a/core/iwasm/libraries/wasi-nn/cmake/wasi_nn.cmake
+++ b/core/iwasm/libraries/wasi-nn/cmake/wasi_nn.cmake
@@ -109,3 +109,24 @@ if(WAMR_BUILD_WASI_NN_LLAMACPP EQUAL 1)
 
   install(TARGETS wasi_nn_llamacpp DESTINATION lib)
 endif()
+
+# - onnx
+if(WAMR_BUILD_WASI_NN_ONNX EQUAL 1)
+  find_package(onnxruntime REQUIRED)
+  enable_language(CXX)
+
+  add_library(
+    wasi_nn_onnx
+    SHARED
+      ${WASI_NN_ROOT}/src/wasi_nn_onnx.cpp
+  )
+
+  target_link_libraries(
+    wasi_nn_onnx
+    PUBLIC
+      vmlib
+      onnxruntime::onnxruntime
+  )
+
+  install(TARGETS wasi_nn_onnx DESTINATION lib)
+endif()
diff --git a/core/iwasm/libraries/wasi-nn/src/wasi_nn.c b/core/iwasm/libraries/wasi-nn/src/wasi_nn.c
index 7921ec9539..787c3a432d 100644
--- a/core/iwasm/libraries/wasi-nn/src/wasi_nn.c
+++ b/core/iwasm/libraries/wasi-nn/src/wasi_nn.c
@@ -33,6 +33,7 @@
 #define TFLITE_BACKEND_LIB "libwasi_nn_tflite" LIB_EXTENTION
 #define OPENVINO_BACKEND_LIB "libwasi_nn_openvino" LIB_EXTENTION
 #define LLAMACPP_BACKEND_LIB "libwasi_nn_llamacpp" LIB_EXTENTION
+#define ONNX_BACKEND_LIB "libwasi_nn_onnx" LIB_EXTENTION
 
 /* Global variables */
 static korp_mutex wasi_nn_lock;
@@ -240,6 +241,17 @@ choose_a_backend()
         return openvino;
     }
 
+#ifndef NDEBUG
+    NN_WARN_PRINTF("%s", dlerror());
+#endif
+
+    handle = dlopen(ONNX_BACKEND_LIB, RTLD_LAZY);
+    if (handle) {
+        NN_INFO_PRINTF("Using onnx backend");
+        dlclose(handle);
+        return onnx;
+    }
+
 #ifndef NDEBUG
     NN_WARN_PRINTF("%s", dlerror());
 #endif
@@ -363,6 +375,8 @@ graph_encoding_to_backend_lib_name(graph_encoding encoding)
             return TFLITE_BACKEND_LIB;
         case ggml:
             return LLAMACPP_BACKEND_LIB;
+        case onnx:
+            return ONNX_BACKEND_LIB;
         default:
             return NULL;
     }
diff --git a/core/iwasm/libraries/wasi-nn/src/wasi_nn_onnx.cpp b/core/iwasm/libraries/wasi-nn/src/wasi_nn_onnx.cpp
new file mode 100644
index 0000000000..44d8d66135
--- /dev/null
+++ b/core/iwasm/libraries/wasi-nn/src/wasi_nn_onnx.cpp
@@ -0,0 +1,795 @@
+/*
+ * Copyright 2025 Sony Semiconductor Solutions Corporation.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+#include <dlfcn.h>
+#include <stdlib.h>
+#include <string.h>
+#include <mutex>
+#include <vector>
+#include <unordered_map>
+#include "bh_platform.h"
+#include "wasi_nn_backend.h"
+#include "utils/logger.h"
+#include "onnxruntime_c_api.h"
+
+#if WASM_ENABLE_WASI_EPHEMERAL_NN == 0
+#error This backend doesn't support legacy "wasi_nn" abi. Please enable WASM_ENABLE_WASI_EPHEMERAL_NN.
+#endif
+
+/* Maximum number of graphs and execution contexts */
+#define MAX_GRAPHS 4
+#define MAX_CONTEXTS 4
+
+/* Graph structure */
+typedef struct {
+    OrtSession *session;
+    bool is_initialized;
+} OnnxRuntimeGraph;
+
+/* Execution context structure */
+typedef struct {
+    OrtMemoryInfo *memory_info;
+    std::vector<const char *> input_names;
+    std::vector<const char *> output_names;
+    std::unordered_map<uint32_t, OrtValue *> inputs;
+    std::unordered_map<uint32_t, OrtValue *> outputs;
+    OnnxRuntimeGraph *graph;
+    bool is_initialized;
+} OnnxRuntimeExecCtx;
+
+/* ONNX Runtime context structure */
+typedef struct {
+    OrtEnv *env;
+    OrtSessionOptions *session_options;
+    OrtAllocator *allocator;
+    const OrtApi *ort_api;
+    std::mutex mutex;
+    bool is_initialized;
+    OnnxRuntimeGraph graphs[MAX_GRAPHS];
+    OnnxRuntimeExecCtx exec_ctxs[MAX_CONTEXTS];
+} OnnxRuntimeContext;
+
+static wasi_nn_error
+convert_ort_error_to_wasi_nn_error(const OnnxRuntimeContext *ctx,
+                                   OrtStatus *status)
+{
+    if (status == nullptr) {
+        return success;
+    }
+
+    wasi_nn_error err;
+    OrtErrorCode code = ctx->ort_api->GetErrorCode(status);
+    const char *msg = ctx->ort_api->GetErrorMessage(status);
+
+    NN_ERR_PRINTF("ONNX Runtime error: %s", msg);
+
+    switch (code) {
+        case ORT_INVALID_ARGUMENT:
+            err = invalid_argument;
+            break;
+        case ORT_RUNTIME_EXCEPTION:
+            err = runtime_error;
+            break;
+        case ORT_NOT_IMPLEMENTED:
+            err = unsupported_operation;
+            break;
+        case ORT_INVALID_PROTOBUF:
+            err = invalid_encoding;
+            break;
+        case ORT_MODEL_LOADED:
+            err = too_large;
+            break;
+        case ORT_INVALID_GRAPH:
+            err = invalid_encoding;
+            break;
+        default:
+            err = runtime_error;
+            break;
+    }
+
+    ctx->ort_api->ReleaseStatus(status);
+    return err;
+}
+
+static bool
+convert_wasi_nn_type_to_ort_type(tensor_type type,
+                                 ONNXTensorElementDataType *ort_type)
+{
+    switch (type) {
+        case fp32:
+            *ort_type = ONNX_TENSOR_ELEMENT_DATA_TYPE_FLOAT;
+            break;
+        case fp16:
+            *ort_type = ONNX_TENSOR_ELEMENT_DATA_TYPE_FLOAT16;
+            break;
+        case fp64:
+            *ort_type = ONNX_TENSOR_ELEMENT_DATA_TYPE_DOUBLE;
+            break;
+        case u8:
+            *ort_type = ONNX_TENSOR_ELEMENT_DATA_TYPE_UINT8;
+            break;
+        case i32:
+            *ort_type = ONNX_TENSOR_ELEMENT_DATA_TYPE_INT32;
+            break;
+        case i64:
+            *ort_type = ONNX_TENSOR_ELEMENT_DATA_TYPE_INT64;
+            break;
+        default:
+            NN_WARN_PRINTF("Unsupported wasi-nn tensor type: %d", type);
+            return false;
+    }
+    return true;
+}
+
+/* Backend API implementation */
+
+extern "C" {
+
+__attribute__((visibility("default"))) wasi_nn_error
+init_backend(void **onnx_ctx)
+{
+    wasi_nn_error err = success;
+    OrtStatus *status = nullptr;
+    OnnxRuntimeContext *ctx = nullptr;
+    ctx = new OnnxRuntimeContext();
+    ctx->ort_api = OrtGetApiBase()->GetApi(ORT_API_VERSION);
+    if (!ctx->ort_api) {
+        NN_ERR_PRINTF("Failed to get ONNX Runtime API");
+        err = runtime_error;
+        goto fail;
+    }
+
+    NN_INFO_PRINTF("Creating ONNX Runtime environment...");
+    status = ctx->ort_api->CreateEnv(ORT_LOGGING_LEVEL_VERBOSE, "wasi-nn",
+                                     &ctx->env);
+    if (status != nullptr) {
+        const char *error_message = ctx->ort_api->GetErrorMessage(status);
+        err = convert_ort_error_to_wasi_nn_error(ctx, status);
+        NN_ERR_PRINTF("Failed to create ONNX Runtime environment: %s",
+                      error_message);
+        goto fail;
+    }
+    NN_INFO_PRINTF("ONNX Runtime environment created successfully");
+
+    status = ctx->ort_api->CreateSessionOptions(&ctx->session_options);
+    if (status != nullptr) {
+        err = convert_ort_error_to_wasi_nn_error(ctx, status);
+        ctx->ort_api->ReleaseEnv(ctx->env);
+        NN_ERR_PRINTF("Failed to create ONNX Runtime session options");
+        goto fail;
+    }
+
+    status = ctx->ort_api->SetSessionGraphOptimizationLevel(
+        ctx->session_options, ORT_ENABLE_BASIC);
+    if (status != nullptr) {
+        err = convert_ort_error_to_wasi_nn_error(ctx, status);
+        ctx->ort_api->ReleaseSessionOptions(ctx->session_options);
+        ctx->ort_api->ReleaseEnv(ctx->env);
+        NN_ERR_PRINTF("Failed to set graph optimization level");
+        goto fail;
+    }
+
+    status = ctx->ort_api->GetAllocatorWithDefaultOptions(&ctx->allocator);
+    if (status != nullptr) {
+        err = convert_ort_error_to_wasi_nn_error(ctx, status);
+        ctx->ort_api->ReleaseSessionOptions(ctx->session_options);
+        ctx->ort_api->ReleaseEnv(ctx->env);
+        NN_ERR_PRINTF("Failed to get default allocator");
+        goto fail;
+    }
+
+    for (int i = 0; i < MAX_GRAPHS; i++) {
+        ctx->graphs[i].is_initialized = false;
+        ctx->graphs[i].session = nullptr;
+    }
+
+    for (int i = 0; i < MAX_CONTEXTS; i++) {
+        ctx->exec_ctxs[i].is_initialized = false;
+        ctx->exec_ctxs[i].memory_info = nullptr;
+        ctx->exec_ctxs[i].graph = nullptr;
+        ctx->exec_ctxs[i].input_names.clear();
+        ctx->exec_ctxs[i].output_names.clear();
+        ctx->exec_ctxs[i].inputs.clear();
+        ctx->exec_ctxs[i].outputs.clear();
+    }
+
+    ctx->is_initialized = true;
+    *onnx_ctx = ctx;
+
+    NN_INFO_PRINTF("ONNX Runtime backend initialized");
+    return success;
+
+fail:
+    delete (ctx);
+    return err;
+}
+
+__attribute__((visibility("default"))) wasi_nn_error
+deinit_backend(void *onnx_ctx)
+{
+    OnnxRuntimeContext *ctx = (OnnxRuntimeContext *)onnx_ctx;
+    std::lock_guard<std::mutex> lock(ctx->mutex);
+
+    if (!ctx->is_initialized) {
+        return success;
+    }
+
+    for (int i = 0; i < MAX_GRAPHS; i++) {
+        if (ctx->graphs[i].is_initialized) {
+            ctx->ort_api->ReleaseSession(ctx->graphs[i].session);
+            ctx->graphs[i].is_initialized = false;
+        }
+    }
+
+    for (int i = 0; i < MAX_CONTEXTS; i++) {
+        if (ctx->exec_ctxs[i].is_initialized) {
+            for (auto &input : ctx->exec_ctxs[i].inputs) {
+                ctx->ort_api->ReleaseValue(input.second);
+            }
+            for (auto &output : ctx->exec_ctxs[i].outputs) {
+                ctx->ort_api->ReleaseValue(output.second);
+            }
+
+            for (auto name : ctx->exec_ctxs[i].input_names) {
+                free((void *)name);
+            }
+            ctx->exec_ctxs[i].input_names.clear();
+
+            for (auto name : ctx->exec_ctxs[i].output_names) {
+                free((void *)name);
+            }
+            ctx->exec_ctxs[i].output_names.clear();
+
+            ctx->ort_api->ReleaseMemoryInfo(ctx->exec_ctxs[i].memory_info);
+            ctx->exec_ctxs[i].is_initialized = false;
+        }
+    }
+
+    ctx->ort_api->ReleaseSessionOptions(ctx->session_options);
+    ctx->ort_api->ReleaseEnv(ctx->env);
+    ctx->is_initialized = false;
+
+    delete (ctx);
+
+    NN_INFO_PRINTF("ONNX Runtime backend deinitialized");
+    return success;
+}
+
+__attribute__((visibility("default"))) wasi_nn_error
+load(void *onnx_ctx, graph_builder_array *builder, graph_encoding encoding,
+     execution_target target, graph *g)
+{
+    if (!onnx_ctx) {
+        return runtime_error;
+    }
+
+    if (encoding != onnx) {
+        NN_ERR_PRINTF("Unsupported encoding: %d", encoding);
+        return invalid_encoding;
+    }
+
+    if (target != cpu) {
+        NN_ERR_PRINTF("Only CPU target is supported");
+        return unsupported_operation;
+    }
+
+    OnnxRuntimeContext *ctx = (OnnxRuntimeContext *)onnx_ctx;
+    std::lock_guard<std::mutex> lock(ctx->mutex);
+
+    int graph_index = -1;
+    for (int i = 0; i < MAX_GRAPHS; i++) {
+        if (!ctx->graphs[i].is_initialized) {
+            graph_index = i;
+            break;
+        }
+    }
+
+    if (graph_index == -1) {
+        NN_ERR_PRINTF("Maximum number of graphs reached");
+        return runtime_error;
+    }
+
+    if (builder->size == 0 || builder->buf == NULL) {
+        NN_ERR_PRINTF("No model data provided");
+        return invalid_argument;
+    }
+
+    NN_INFO_PRINTF("[ONNX Runtime] Loading model of size %zu bytes...",
+                   builder->buf[0].size);
+
+    if (builder->buf[0].size > 16) {
+        NN_INFO_PRINTF(
+            "Model header bytes: %02x %02x %02x %02x %02x %02x %02x %02x",
+            ((uint8_t *)builder->buf[0].buf)[0],
+            ((uint8_t *)builder->buf[0].buf)[1],
+            ((uint8_t *)builder->buf[0].buf)[2],
+            ((uint8_t *)builder->buf[0].buf)[3],
+            ((uint8_t *)builder->buf[0].buf)[4],
+            ((uint8_t *)builder->buf[0].buf)[5],
+            ((uint8_t *)builder->buf[0].buf)[6],
+            ((uint8_t *)builder->buf[0].buf)[7]);
+    }
+
+    OrtStatus *status = ctx->ort_api->CreateSessionFromArray(
+        ctx->env, builder->buf[0].buf, builder->buf[0].size,
+        ctx->session_options, &ctx->graphs[graph_index].session);
+
+    if (status != nullptr) {
+        const char *error_message = ctx->ort_api->GetErrorMessage(status);
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ctx, status);
+        NN_ERR_PRINTF("Failed to create ONNX Runtime session: %s",
+                      error_message);
+        return err;
+    }
+
+    NN_INFO_PRINTF("ONNX Runtime session created successfully");
+
+    ctx->graphs[graph_index].is_initialized = true;
+    *g = graph_index;
+
+    NN_INFO_PRINTF("ONNX model loaded as graph %d", graph_index);
+    return success;
+}
+
+__attribute__((visibility("default"))) wasi_nn_error
+load_by_name(void *onnx_ctx, const char *name, uint32_t filename_len, graph *g)
+{
+    if (!onnx_ctx) {
+        return runtime_error;
+    }
+
+    OnnxRuntimeContext *ctx = (OnnxRuntimeContext *)onnx_ctx;
+    std::lock_guard<std::mutex> lock(ctx->mutex);
+
+    int graph_index = -1;
+    for (int i = 0; i < MAX_GRAPHS; i++) {
+        if (!ctx->graphs[i].is_initialized) {
+            graph_index = i;
+            break;
+        }
+    }
+
+    if (graph_index == -1) {
+        NN_ERR_PRINTF("Maximum number of graphs reached");
+        return runtime_error;
+    }
+
+    OrtStatus *status =
+        ctx->ort_api->CreateSession(ctx->env, name, ctx->session_options,
+                                    &ctx->graphs[graph_index].session);
+
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ctx, status);
+        NN_ERR_PRINTF("Failed to create ONNX Runtime session from file: %s",
+                      name);
+        return err;
+    }
+
+    ctx->graphs[graph_index].is_initialized = true;
+    *g = graph_index;
+
+    NN_INFO_PRINTF("ONNX model loaded from file %s as graph %d", name,
+                   graph_index);
+    return success;
+}
+
+__attribute__((visibility("default"))) wasi_nn_error
+init_execution_context(void *onnx_ctx, graph g, graph_execution_context *ctx)
+{
+    OnnxRuntimeContext *ort_ctx = (OnnxRuntimeContext *)onnx_ctx;
+    if (!onnx_ctx) {
+        return runtime_error;
+    }
+
+    std::lock_guard<std::mutex> lock(ort_ctx->mutex);
+
+    if (g >= MAX_GRAPHS || !ort_ctx->graphs[g].is_initialized) {
+        NN_ERR_PRINTF("Invalid graph handle: %d", g);
+        return invalid_argument;
+    }
+
+    int ctx_index = -1;
+    for (int i = 0; i < MAX_CONTEXTS; i++) {
+        if (!ort_ctx->exec_ctxs[i].is_initialized) {
+            ctx_index = i;
+            break;
+        }
+    }
+
+    if (ctx_index == -1) {
+        NN_ERR_PRINTF("Maximum number of execution contexts reached");
+        return runtime_error;
+    }
+
+    OnnxRuntimeExecCtx *exec_ctx = &ort_ctx->exec_ctxs[ctx_index];
+    exec_ctx->graph = &ort_ctx->graphs[g];
+
+    OrtStatus *status = ort_ctx->ort_api->CreateCpuMemoryInfo(
+        OrtArenaAllocator, OrtMemTypeDefault, &exec_ctx->memory_info);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        NN_ERR_PRINTF("Failed to create CPU memory info");
+        return err;
+    }
+
+    size_t num_input_nodes;
+    status = ort_ctx->ort_api->SessionGetInputCount(exec_ctx->graph->session,
+                                                    &num_input_nodes);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        ort_ctx->ort_api->ReleaseMemoryInfo(exec_ctx->memory_info);
+        NN_ERR_PRINTF("Failed to get input count");
+        return err;
+    }
+
+    for (size_t i = 0; i < num_input_nodes; i++) {
+        char *input_name;
+        status = ort_ctx->ort_api->SessionGetInputName(
+            exec_ctx->graph->session, i, ort_ctx->allocator, &input_name);
+        if (status != nullptr) {
+            wasi_nn_error err =
+                convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+            ort_ctx->ort_api->ReleaseMemoryInfo(exec_ctx->memory_info);
+            NN_ERR_PRINTF("Failed to get input name");
+            return err;
+        }
+        exec_ctx->input_names.push_back(input_name);
+    }
+
+    size_t num_output_nodes;
+    status = ort_ctx->ort_api->SessionGetOutputCount(exec_ctx->graph->session,
+                                                     &num_output_nodes);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        ort_ctx->ort_api->ReleaseMemoryInfo(exec_ctx->memory_info);
+        for (const char *name : exec_ctx->input_names) {
+            ort_ctx->allocator->Free(ort_ctx->allocator, (void *)name);
+        }
+        NN_ERR_PRINTF("Failed to get output count");
+        return err;
+    }
+
+    for (size_t i = 0; i < num_output_nodes; i++) {
+        char *output_name;
+        status = ort_ctx->ort_api->SessionGetOutputName(
+            exec_ctx->graph->session, i, ort_ctx->allocator, &output_name);
+        if (status != nullptr) {
+            wasi_nn_error err =
+                convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+            ort_ctx->ort_api->ReleaseMemoryInfo(exec_ctx->memory_info);
+            for (const char *name : exec_ctx->input_names) {
+                ort_ctx->allocator->Free(ort_ctx->allocator, (void *)name);
+            }
+            NN_ERR_PRINTF("Failed to get output name");
+            return err;
+        }
+        exec_ctx->output_names.push_back(output_name);
+    }
+
+    exec_ctx->is_initialized = true;
+    *ctx = ctx_index;
+
+    NN_INFO_PRINTF("Execution context %d initialized for graph %d", ctx_index,
+                   g);
+    return success;
+}
+
+__attribute__((visibility("default"))) wasi_nn_error
+set_input(void *onnx_ctx, graph_execution_context ctx, uint32_t index,
+          tensor *input_tensor)
+{
+    OnnxRuntimeContext *ort_ctx = (OnnxRuntimeContext *)onnx_ctx;
+    if (!onnx_ctx) {
+        return runtime_error;
+    }
+
+    std::lock_guard<std::mutex> lock(ort_ctx->mutex);
+
+    if (ctx >= MAX_CONTEXTS || !ort_ctx->exec_ctxs[ctx].is_initialized) {
+        NN_ERR_PRINTF("Invalid execution context handle: %d", ctx);
+        return invalid_argument;
+    }
+
+    if (index >= ort_ctx->exec_ctxs[ctx].input_names.size()) {
+        NN_ERR_PRINTF("Invalid input index: %d (max: %zu)", index,
+                      ort_ctx->exec_ctxs[ctx].input_names.size() - 1);
+        return invalid_argument;
+    }
+
+    OnnxRuntimeExecCtx *exec_ctx = &ort_ctx->exec_ctxs[ctx];
+
+    OrtTypeInfo *type_info = nullptr;
+    OrtStatus *status = ort_ctx->ort_api->SessionGetInputTypeInfo(
+        exec_ctx->graph->session, index, &type_info);
+    if (status != nullptr) {
+        ort_ctx->ort_api->ReleaseTypeInfo(type_info);
+        return runtime_error;
+    }
+
+    const OrtTensorTypeAndShapeInfo *tensor_info;
+    status =
+        ort_ctx->ort_api->CastTypeInfoToTensorInfo(type_info, &tensor_info);
+    if (status != nullptr) {
+        ort_ctx->ort_api->ReleaseTypeInfo(type_info);
+        return runtime_error;
+    }
+
+    size_t num_model_dims;
+    status = ort_ctx->ort_api->GetDimensionsCount(tensor_info, &num_model_dims);
+    std::vector<int64_t> model_dims(num_model_dims);
+    status = ort_ctx->ort_api->GetDimensions(tensor_info, model_dims.data(),
+                                             num_model_dims);
+
+    void *input_tensor_data = input_tensor->data.buf;
+    void *input_tensor_scaled_data = NULL;
+    ort_ctx->ort_api->ReleaseTypeInfo(type_info);
+    size_t num_dims = input_tensor->dimensions->size;
+    int64_t *ort_dims = (int64_t *)malloc(num_dims * sizeof(int64_t));
+    if (!ort_dims) {
+        NN_ERR_PRINTF("Failed to allocate memory for tensor dimensions");
+        return runtime_error;
+    }
+
+    for (size_t i = 0; i < num_dims; i++) {
+        ort_dims[i] = input_tensor->dimensions->buf[i];
+    }
+
+    ONNXTensorElementDataType ort_type;
+    if (!convert_wasi_nn_type_to_ort_type(
+            static_cast<tensor_type>(input_tensor->type), &ort_type)) {
+        NN_ERR_PRINTF("Failed to convert tensor type");
+        return runtime_error;
+    }
+
+    OrtValue *input_value = nullptr;
+    size_t total_elements = 1;
+    for (size_t i = 0; i < num_dims; i++) {
+        total_elements *= input_tensor->dimensions->buf[i];
+    }
+
+    status = ort_ctx->ort_api->CreateTensorWithDataAsOrtValue(
+        exec_ctx->memory_info, input_tensor->data.buf, input_tensor->data.size,
+        ort_dims, num_dims, ort_type, &input_value);
+
+    free(ort_dims);
+
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        NN_ERR_PRINTF("Failed to create input tensor");
+        return err;
+    }
+
+    if (exec_ctx->inputs.count(index) > 0) {
+        ort_ctx->ort_api->ReleaseValue(exec_ctx->inputs[index]);
+    }
+    exec_ctx->inputs[index] = input_value;
+
+    NN_INFO_PRINTF("Input tensor set for context %d, index %d", ctx, index);
+    return success;
+}
+
+__attribute__((visibility("default"))) wasi_nn_error
+compute(void *onnx_ctx, graph_execution_context ctx)
+{
+    OnnxRuntimeContext *ort_ctx = (OnnxRuntimeContext *)onnx_ctx;
+    if (!onnx_ctx) {
+        return runtime_error;
+    }
+
+    std::lock_guard<std::mutex> lock(ort_ctx->mutex);
+
+    if (ctx >= MAX_CONTEXTS || !ort_ctx->exec_ctxs[ctx].is_initialized) {
+        NN_ERR_PRINTF("Invalid execution context handle: %d", ctx);
+        return invalid_argument;
+    }
+
+    OnnxRuntimeExecCtx *exec_ctx = &ort_ctx->exec_ctxs[ctx];
+
+    std::vector<OrtValue *> input_values;
+    std::vector<const char *> input_names;
+
+    for (size_t i = 0; i < exec_ctx->input_names.size(); i++) {
+        if (exec_ctx->inputs.count(i) == 0) {
+            NN_ERR_PRINTF("Input tensor not set for index %zu", i);
+            return invalid_argument;
+        }
+        input_values.push_back(exec_ctx->inputs[i]);
+        input_names.push_back(exec_ctx->input_names[i]);
+    }
+
+    for (auto &output : exec_ctx->outputs) {
+        ort_ctx->ort_api->ReleaseValue(output.second);
+    }
+    exec_ctx->outputs.clear();
+
+    std::vector<OrtValue *> output_values(exec_ctx->output_names.size());
+
+    OrtStatus *status = ort_ctx->ort_api->Run(
+        exec_ctx->graph->session, nullptr, input_names.data(),
+        input_values.data(), input_values.size(), exec_ctx->output_names.data(),
+        exec_ctx->output_names.size(), output_values.data());
+
+    for (size_t i = 0; i < output_values.size(); i++) {
+        exec_ctx->outputs[i] = output_values[i];
+    }
+
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        NN_ERR_PRINTF("Failed to run inference");
+        return err;
+    }
+
+    NN_INFO_PRINTF("Inference computed for context %d", ctx);
+    return success;
+}
+
+__attribute__((visibility("default"))) wasi_nn_error
+get_output(void *onnx_ctx, graph_execution_context ctx, uint32_t index,
+           tensor_data *out_buffer, uint32_t *out_buffer_size)
+{
+    OnnxRuntimeContext *ort_ctx = (OnnxRuntimeContext *)onnx_ctx;
+    if (!onnx_ctx) {
+        return runtime_error;
+    }
+
+    std::lock_guard<std::mutex> lock(ort_ctx->mutex);
+
+    if (ctx >= MAX_CONTEXTS || !ort_ctx->exec_ctxs[ctx].is_initialized) {
+        NN_ERR_PRINTF("Invalid execution context handle: %d", ctx);
+        return invalid_argument;
+    }
+
+    if (index >= ort_ctx->exec_ctxs[ctx].output_names.size()) {
+        NN_ERR_PRINTF("Invalid output index: %d (max: %zu)", index,
+                      ort_ctx->exec_ctxs[ctx].output_names.size() - 1);
+        return invalid_argument;
+    }
+
+    OnnxRuntimeExecCtx *exec_ctx = &ort_ctx->exec_ctxs[ctx];
+
+    OrtValue *output_value = exec_ctx->outputs[index];
+    if (!output_value) {
+        NN_ERR_PRINTF("Output tensor not available for index %d", index);
+        return runtime_error;
+    }
+
+    OrtTensorTypeAndShapeInfo *tensor_info;
+    OrtStatus *status =
+        ort_ctx->ort_api->GetTensorTypeAndShape(output_value, &tensor_info);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        NN_ERR_PRINTF("Failed to get tensor type and shape");
+        return err;
+    }
+
+    ONNXTensorElementDataType element_type;
+    status = ort_ctx->ort_api->GetTensorElementType(tensor_info, &element_type);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        ort_ctx->ort_api->ReleaseTensorTypeAndShapeInfo(tensor_info);
+        NN_ERR_PRINTF("Failed to get tensor element type");
+        return err;
+    }
+
+    size_t num_dims;
+    status = ort_ctx->ort_api->GetDimensionsCount(tensor_info, &num_dims);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        ort_ctx->ort_api->ReleaseTensorTypeAndShapeInfo(tensor_info);
+        NN_ERR_PRINTF("Failed to get tensor dimensions count");
+        return err;
+    }
+
+    int64_t *dims = (int64_t *)malloc(num_dims * sizeof(int64_t));
+    if (!dims) {
+        ort_ctx->ort_api->ReleaseTensorTypeAndShapeInfo(tensor_info);
+        NN_ERR_PRINTF("Failed to allocate memory for tensor dimensions");
+        return runtime_error;
+    }
+
+    status = ort_ctx->ort_api->GetDimensions(tensor_info, dims, num_dims);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        free(dims);
+        ort_ctx->ort_api->ReleaseTensorTypeAndShapeInfo(tensor_info);
+        NN_ERR_PRINTF("Failed to get tensor dimensions");
+        return err;
+    }
+
+    size_t tensor_size;
+    status =
+        ort_ctx->ort_api->GetTensorShapeElementCount(tensor_info, &tensor_size);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        free(dims);
+        ort_ctx->ort_api->ReleaseTensorTypeAndShapeInfo(tensor_info);
+        NN_ERR_PRINTF("Failed to get tensor element count");
+        return err;
+    }
+
+    NN_INFO_PRINTF("Output tensor dimensions: ");
+    for (size_t i = 0; i < num_dims; i++) {
+        NN_INFO_PRINTF("  dim[%zu] = %lld", i, dims[i]);
+    }
+    NN_INFO_PRINTF("Total elements: %zu", tensor_size);
+
+    ort_ctx->ort_api->ReleaseTensorTypeAndShapeInfo(tensor_info);
+    free(dims);
+
+    if (tensor_size == 0) {
+        NN_ERR_PRINTF("Tensor is empty (zero elements)");
+        return runtime_error;
+    }
+
+    void *tensor_data = nullptr;
+    status = ort_ctx->ort_api->GetTensorMutableData(output_value, &tensor_data);
+    if (status != nullptr) {
+        wasi_nn_error err = convert_ort_error_to_wasi_nn_error(ort_ctx, status);
+        NN_ERR_PRINTF("Failed to get tensor data");
+        return err;
+    }
+
+    if (tensor_data == nullptr) {
+        NN_ERR_PRINTF("Tensor data pointer is null");
+        return runtime_error;
+    }
+
+    size_t element_size;
+    switch (element_type) {
+        case ONNX_TENSOR_ELEMENT_DATA_TYPE_FLOAT:
+            element_size = sizeof(float);
+            break;
+        case ONNX_TENSOR_ELEMENT_DATA_TYPE_FLOAT16:
+            element_size = sizeof(uint16_t);
+            break;
+        case ONNX_TENSOR_ELEMENT_DATA_TYPE_DOUBLE:
+            element_size = sizeof(double);
+            break;
+        case ONNX_TENSOR_ELEMENT_DATA_TYPE_INT32:
+            element_size = sizeof(int32_t);
+            break;
+        case ONNX_TENSOR_ELEMENT_DATA_TYPE_INT64:
+            element_size = sizeof(int64_t);
+            break;
+        case ONNX_TENSOR_ELEMENT_DATA_TYPE_UINT8:
+            element_size = sizeof(uint8_t);
+            break;
+        default:
+            NN_ERR_PRINTF("Unsupported tensor element type: %d", element_type);
+            return unsupported_operation;
+    }
+
+    size_t output_size_bytes = tensor_size * element_size;
+    if (out_buffer->size < output_size_bytes) {
+        NN_ERR_PRINTF(
+            "Output buffer too small: %u bytes provided, %zu bytes needed",
+            out_buffer->size, output_size_bytes);
+        *out_buffer_size = output_size_bytes;
+        return too_large;
+    }
+    NN_INFO_PRINTF("Output tensor size: %zu elements, element size: %zu bytes, "
+                   "total: %zu bytes",
+                   tensor_size, element_size, output_size_bytes);
+
+    if (tensor_data == nullptr) {
+        NN_ERR_PRINTF("Tensor data is null");
+        return runtime_error;
+    }
+
+    if (out_buffer->buf == nullptr) {
+        NN_ERR_PRINTF("Output buffer is null");
+        return invalid_argument;
+    }
+
+    memcpy(out_buffer->buf, tensor_data, output_size_bytes);
+    *out_buffer_size = output_size_bytes;
+
+    NN_INFO_PRINTF(
+        "Output tensor retrieved for context %d, index %d, size %zu bytes", ctx,
+        index, output_size_bytes);
+    return success;
+}
+
+} /* End of extern "C" */