diff --git a/tools/autobuild/build-downloads.py b/tools/autobuild/build-downloads.py
new file mode 100755
index 000000000..0f532e8bf
--- /dev/null
+++ b/tools/autobuild/build-downloads.py
@@ -0,0 +1,58 @@
+#!/usr/bin/env python3
+
+import glob
+import json
+import os
+import sys
+
+
+def main(repo_path, output_path):
+    boards_index = []
+    board_ids = set()
+
+    for board_json in glob.glob(os.path.join(repo_path, "ports/*/boards/*/board.json")):
+        # Relative path to the board directory (e.g. "ports/stm32/boards/PYBV11").
+        board_dir = os.path.dirname(board_json)
+        # Relative path to the port (e.g. "ports/stm32")
+        port_dir = os.path.dirname(os.path.dirname(board_dir))
+
+        with open(board_json, "r") as f:
+            blob = json.load(f)
+
+            # Use "id" if specified, otherwise default to board dir (e.g. "PYBV11").
+            # We allow boards to override ID for the historical build names.
+            blob["id"] = blob.get("id", os.path.basename(board_dir))
+
+            # Check for duplicate board IDs.
+            if blob["id"] in board_ids:
+                print("Duplicate board ID: '{}'".format(blob["id"]), file=sys.stderr)
+            board_ids.add(blob["id"])
+
+            # Add in default fields.
+            blob["port"] = os.path.basename(port_dir)
+            blob["build"] = os.path.basename(board_dir)
+            boards_index.append(blob)
+
+        # Create the board markdown, which is the concatenation of the
+        # default "board.md" file (if exists), as well as any flashing
+        # instructions.
+        board_markdown = os.path.join(board_dir, "board.md")
+        with open(os.path.join(output_path, blob["id"] + ".md"), "w") as f:
+            if os.path.exists(board_markdown):
+                with open(board_markdown, "r") as fin:
+                    f.write(fin.read())
+
+            if blob["deploy"]:
+                f.write("\n\n## Installation instructions\n")
+            for deploy in blob["deploy"]:
+                with open(os.path.join(board_dir, deploy), "r") as fin:
+                    f.write(fin.read())
+
+    # Write the full index for the website to load.
+    with open(os.path.join(output_path, "index.json"), "w") as f:
+        json.dump(boards_index, f, indent=4, sort_keys=True)
+        f.write("\n")
+
+
+if __name__ == "__main__":
+    main(sys.argv[1], sys.argv[2])