Nomad changes

docs/snippets/c/plugins/plugin_extractor.md

@@ -0,0 +1,42 @@
+```c title="C"
+#include <kreuzberg.h>
+#include <stdio.h>
+#include <string.h>
+
+/*
+ * The C FFI exposes vtable-based registration for OCR backends, post-processors,
+ * validators, and embedding backends. There is no public C entry point for
+ * registering a custom DocumentExtractor — that must be done from Rust.
+ *
+ * From C you can still drive extraction for any MIME type the Rust core knows
+ * how to handle. The example below feeds JSON bytes through the standard
+ * extraction pipeline by passing the explicit MIME type.
+ */
+
+int main(void) {
+    const char *json_payload = "{\"message\":\"Hello, world!\"}";
+    const uint8_t *bytes = (const uint8_t *)json_payload;
+    uintptr_t bytes_len = (uintptr_t)strlen(json_payload);
+
+    KREUZBERGExtractionResult *result = kreuzberg_extract_bytes_sync(
+        bytes,
+        bytes_len,
+        "application/json",
+        NULL
+    );
+
+    if (!result) {
+        fprintf(stderr, "extraction failed (code %d): %s\n",
+                kreuzberg_last_error_code(),
+                kreuzberg_last_error_context());
+        return 1;
+    }
+
+    char *content = kreuzberg_extraction_result_content(result);
+    printf("Extracted JSON content: %s\n", content ? content : "(empty)");
+
+    kreuzberg_free_string(content);
+    kreuzberg_extraction_result_free(result);
+    return 0;
+}
+```