diff --git a/src/plugins_exts_compile.h b/src/plugins_exts_compile.h
index 5925350..0fbe43b 100644
--- a/src/plugins_exts_compile.h
+++ b/src/plugins_exts_compile.h
@@ -111,7 +111,7 @@
  * supposed to use this function when the extension instance's substatements are supposed to be compiled in a standard way
  * (or if just the @ref scflags are enough to modify the compilation process).
  *
- * @param[in] ctx YANG schema compile context to track the compilation state.
+ * @param[in] ctx Compile context.
  * @param[in] ext_p Parsed representation of the extension instance being processed.
  * @param[in,out] ext Compiled extension instance with the prepared ::lysc_ext_instance.substmts array, which will be updated
  * by storing the compiled data.
@@ -123,6 +123,36 @@
         struct lysc_ext_instance *ext);
 
 /**
+ * @brief Compile substatements of an extension instance but append all schema data nodes as augments.
+ *
+ * Similar to ::lys_compile_extension_instance().
+ *
+ * @param[in] ctx Compile context.
+ * @param[in] ext_p Parsed representation of the extension instance being processed.
+ * @param[in,out] ext Compiled extension instance with the prepared ::lysc_ext_instance.substmts array, which will be updated
+ * by storing the compiled data except for schema data nodes.
+ * @param[in] aug_target Augment target node to append schema data nodes.
+ * @return LY_SUCCESS on success.
+ * @return LY_EVALID if compilation of the substatements fails.
+ * @return LY_ENOT if the extension is disabled (by if-feature) and should be ignored.
+ */
+LIBYANG_API_DECL LY_ERR lys_compile_extension_instance_augment(struct lysc_ctx *ctx, const struct lysp_ext_instance *ext_p,
+        struct lysc_ext_instance *ext, struct lysc_node *aug_target);
+
+/**
+ * @brief Find augment target in an extension.
+ *
+ * @param[in] ctx Compile context.
+ * @param[in] path Absolute-schema-nodeid representing the augment target. The first segment is expected to identify
+ * the specific extension instance.
+ * @param[out] aug_ext Optional augment target extension.
+ * @param[out] aug_target Augment target compiled schema node.
+ * @return LY_ERR value.
+ */
+LIBYANG_API_DECL LY_ERR lys_compile_extension_instance_find_augment_target(struct lysc_ctx *ctx, const char *path,
+        struct lysc_ext_instance **aug_ext, struct lysc_node **aug_target);
+
+/**
  * @brief Update path in the compile context, which is used for logging where the compilation failed.
  *
  * @param[in] ctx Compile context with the path.