diff --git a/BUILD.bazel b/BUILD.bazel
index 395ec1daa04..cc66f07b489 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -16,7 +16,6 @@ load(
     "xnnpack_if_kleidiai_enabled",
     "xnnpack_min_size_copts",
     "xnnpack_slinky_deps",
-    "xnnpack_slinky_srcs",
     "xnnpack_source_list_file",
     "xnnpack_transitive_source_list",
     "xnnpack_visibility",
@@ -1019,9 +1018,17 @@ xnnpack_cc_library(
     ],
 )
 
+xnnpack_cc_library(
+    name = "subgraph_h",
+    hdrs = [
+        "src/xnnpack/subgraph.h",
+    ],
+    compatible_with = [],
+)
+
 xnnpack_cc_library(
     name = "subgraph",
-    srcs = SUBGRAPH_SRCS + xnnpack_slinky_srcs(),
+    srcs = SUBGRAPH_SRCS,
     hdrs = [
         "src/xnnpack/memory-planner.h",
         "src/xnnpack/reshape-helpers.h",
@@ -1050,6 +1057,7 @@ xnnpack_cc_library(
         ":operators",
         ":params",
         ":requantization",
+        ":subgraph_h",
         ":xnnpack_h",
         "@pthreadpool",
     ] + xnnpack_slinky_deps(),
diff --git a/build_defs.bzl b/build_defs.bzl
index c4ad91206a7..d0e6b7bb614 100644
--- a/build_defs.bzl
+++ b/build_defs.bzl
@@ -62,9 +62,6 @@ def xnnpack_optional_dnnl_deps():
     """Optional Intel DNNL dependencies."""
     return []
 
-def xnnpack_slinky_srcs():
-    return []
-
 def xnnpack_slinky_deps():
     return []
 
diff --git a/src/runtime.c b/src/runtime.c
index a36edcf708b..e0f53697bbc 100644
--- a/src/runtime.c
+++ b/src/runtime.c
@@ -553,8 +553,19 @@ enum xnn_status xnn_create_runtime_v4(
   }
 
 #ifdef XNN_SLINKY_ENABLED
-  runtime->slinky_pipeline = xnn_runtime_to_slinky_pipeline(runtime);
+  // If compiling with XNN_SLINKY_ENABLED defined, assume we always
+  // want Slinky enabled, regardless of the runtime flag
+  const bool use_slinky = true;
+#else
+  const bool use_slinky = (flags & XNN_FLAG_SLINKY_ENABLED) != 0;
 #endif
+  if (use_slinky) {
+    #ifdef XNN_SLINKY_AVAILABLE
+    // slinky_init_pipeline(runtime);
+    #else
+    xnn_log_warning("Slinky requested but not available");
+    #endif
+  }
 
   for (uint32_t i = 0; i < runtime->num_values; i++) {
     struct xnn_value* value = &runtime->values[i];
@@ -695,23 +706,9 @@ enum xnn_status xnn_setup_runtime(
     }
   }
 
-#ifdef XNN_SLINKY_ENABLED
-  size_t input_id = 0, output_id = 0;
-  // Use the runtime values instead of the external values so the order is the
-  // same.
-  for (size_t i = 0; i < runtime->num_values; i++) {
-    struct xnn_value* value = &runtime->values[i];
-    if (xnn_value_is_static(value)) {
-      // The value is constant.
-    } else if (value->flags & XNN_VALUE_FLAG_EXTERNAL_INPUT) {
-      runtime->input_values[input_id++] = value;
-    } else if (value->flags & XNN_VALUE_FLAG_EXTERNAL_OUTPUT) {
-      runtime->output_values[output_id++] = value;
-    }
-  }
-  runtime->num_inputs = input_id;
-  runtime->num_outputs = output_id;
-#endif
+  #ifdef XNN_SLINKY_AVAILABLE
+  // slinky_setup_inputs_and_outputs(runtime);
+  #endif
 
   // Apply runtime state changes.
   for (size_t i = 0; i < num_external_values; i++) {
@@ -794,23 +791,9 @@ enum xnn_status xnn_setup_runtime_v2(
     value->data = external_value->data;
   }
 
-#ifdef XNN_SLINKY_ENABLED
-  size_t input_id = 0, output_id = 0;
-  // Use the runtime values instead of the external values so the order is the
-  // same.
-  for (size_t i = 0; i < runtime->num_values; i++) {
-    struct xnn_value* value = &runtime->values[i];
-    if (xnn_value_is_static(value)) {
-      // The value is constant.
-    } else if (value->flags & XNN_VALUE_FLAG_EXTERNAL_INPUT) {
-      runtime->input_values[input_id++] = value;
-    } else if (value->flags & XNN_VALUE_FLAG_EXTERNAL_OUTPUT) {
-      runtime->output_values[output_id++] = value;
-    }
-  }
-  runtime->num_inputs = input_id;
-  runtime->num_outputs = output_id;
-#endif
+  #ifdef XNN_SLINKY_AVAILABLE
+  // slinky_setup_inputs_and_outputs(runtime);
+  #endif
 
   for (uint32_t opdata_id = 0; opdata_id < runtime->num_ops; opdata_id++) {
     struct xnn_operator_data* opdata = &runtime->opdata[opdata_id];
@@ -981,13 +964,10 @@ enum xnn_status xnn_get_runtime_profiling_info(xnn_runtime_t runtime,
 enum xnn_status xnn_invoke_runtime(
   xnn_runtime_t runtime)
 {
-#ifdef XNN_SLINKY_ENABLED
-  if (runtime->slinky_pipeline) {
-    return evaluate(runtime->slinky_pipeline, runtime->input_values,
-             runtime->num_inputs, runtime->output_values,
-             runtime->num_outputs);
-  }
-#endif
+  #ifdef XNN_SLINKY_AVAILABLE
+  enum xnn_status status;
+  // if (slinky_evaluate(runtime, &status)) return status;
+  #endif
 
   if (runtime->profiling) {
     runtime->start_ts = xnn_read_timer();
@@ -1015,9 +995,10 @@ enum xnn_status xnn_delete_runtime(
   xnn_runtime_t runtime)
 {
   if (runtime != NULL) {
-#ifdef XNN_SLINKY_ENABLED
-    destroy_slinky_pipeline(runtime->slinky_pipeline);
-#endif
+    #ifdef XNN_SLINKY_AVAILABLE
+    // slinky_destroy_pipeline(runtime);
+    #endif
+
     if (runtime->opdata != NULL) {
       for (size_t i = 0; i < runtime->num_ops; i++) {
         for (size_t j = 0; j < XNN_MAX_OPERATOR_OBJECTS; j++) {
diff --git a/src/xnnpack/subgraph.h b/src/xnnpack/subgraph.h
index 93a87a9b524..53235e488da 100644
--- a/src/xnnpack/subgraph.h
+++ b/src/xnnpack/subgraph.h
@@ -34,18 +34,23 @@
 /// Disable fusion of nodes in subgraph. Fusion is enabled by default, set this flag to turn it off.
 #define XNN_FLAG_NO_OPERATOR_FUSION 0x80000000
 
+/// Enable Slinky (if available).
+#define XNN_FLAG_SLINKY_ENABLED 0x40000000
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-#ifdef XNN_SLINKY_ENABLED
-struct xnn_value;
+#ifdef XNN_SLINKY_AVAILABLE
+/// Slinky interface -- unused unless XNN_FLAG_SLINKY_ENABLED is set
 struct slinky_pipeline;
 typedef struct slinky_pipeline* slinky_pipeline_t;
-slinky_pipeline_t xnn_runtime_to_slinky_pipeline(xnn_runtime_t runtime);
-void destroy_slinky_pipeline(slinky_pipeline_t pipeline);
-enum xnn_status evaluate(slinky_pipeline_t p, struct xnn_value* const* input_values, size_t num_inputs, struct xnn_value* const* output_values, size_t num_outputs);
-#endif
+
+void slinky_init_pipeline(xnn_runtime_t runtime);
+void slinky_setup_inputs_and_outputs(xnn_runtime_t runtime);
+void slinky_destroy_pipeline(xnn_runtime_t runtime);
+bool slinky_evaluate(xnn_runtime_t runtime, enum xnn_status* status);
+#endif  // XNN_SLINKY_AVAILABLE
 
 struct xnn_shape {
   size_t num_dims;
@@ -446,13 +451,14 @@ struct xnn_runtime {
   bool has_been_setup;
   bool memory_planned;
 
-#ifdef XNN_SLINKY_ENABLED
+  #ifdef XNN_SLINKY_AVAILABLE
+  // Fields used by Slinky -- unused unless XNN_FLAG_SLINKY_ENABLED is set
   slinky_pipeline_t slinky_pipeline;
-  size_t num_inputs;
-  size_t num_outputs;
-  struct xnn_value* input_values[XNN_MAX_SUBGRAPH_INPUT_OR_OUTPUTS];
-  struct xnn_value* output_values[XNN_MAX_SUBGRAPH_INPUT_OR_OUTPUTS];
-#endif
+  size_t slinky_num_inputs;
+  size_t slinky_num_outputs;
+  struct xnn_value* slinky_input_values[XNN_MAX_SUBGRAPH_INPUT_OR_OUTPUTS];
+  struct xnn_value* slinky_output_values[XNN_MAX_SUBGRAPH_INPUT_OR_OUTPUTS];
+  #endif  // XNN_SLINKY_AVAILABLE
 };
 
 enum xnn_status xnn_insert_clamp_node(xnn_subgraph_t subgraph, float output_min, float output_max, struct xnn_node *node);