diff --git a/script/interleave_binpacks.py b/script/interleave_binpacks.py
new file mode 100644
index 00000000..02888b33
--- /dev/null
+++ b/script/interleave_binpacks.py
@@ -0,0 +1,86 @@
+import struct
+import sys
+import os
+import random
+from pathlib import Path
+
+
+def copy_next_chunk(in_file, out_file):
+    chunk_header = in_file.read(8)
+    assert chunk_header[0:4] == b"BINP"
+    size = struct.unpack("<I", chunk_header[4:])[0]
+
+    out_file.write(chunk_header)
+    data = in_file.read(size)
+    out_file.write(data)
+
+    return size + 8
+
+
+def main():
+    if len(sys.argv) < 4:
+        print("Usage: python interleave_binpacks.py infile1 ... infileN outfile")
+        print("       The output binpack, will contain all data from the input files.")
+        print("       Data is read sequentially from the input, randomly alternating between files.")
+        return
+
+    # open last arg as output file name
+    out_filename = sys.argv[-1]
+    print("outfile: ", out_filename)
+
+    if Path(out_filename).exists():
+        print(
+            "Output path {} already exists. Please specify a path to a file that does not exist.".format(
+                out_filename
+            )
+        )
+        return
+
+    out_file = open(out_filename, "wb")
+
+    # open other args as input file names, and get their sizes
+    in_filenames = []
+    for i in range(1, len(sys.argv) - 1):
+        in_filenames.append(sys.argv[i])
+    print("infiles: ", in_filenames)
+
+    in_files = []
+    in_files_remaining = []
+    for in_filename in in_filenames:
+        in_file = open(in_filename, "rb")
+        in_files.append(in_file)
+        file_size = os.path.getsize(in_filename)
+        in_files_remaining.append(file_size)
+
+    # randomly pick a file, with a probability related to their sizes.
+    # copy from the front and keep track of remaining sizes
+    total_remaining = sum(in_files_remaining)
+    print("Merging {} bytes ".format(total_remaining))
+
+    total_size = 0
+    report_every = 100
+    prev_mib = -report_every
+
+    while total_remaining > 0:
+        where = random.randrange(total_remaining)
+        i = 0
+        while where >= in_files_remaining[i]:
+            where -= in_files_remaining[i]
+            i += 1
+        size = copy_next_chunk(in_files[i], out_file)
+        in_files_remaining[i] -= size
+        total_remaining -= size
+        total_size += size
+        mib = total_size // 1024 // 1024
+        if mib // 100 != prev_mib // 100:
+            print("Copied {} MiB".format(mib))
+            prev_mib = mib
+
+    out_file.close()
+    for in_file in in_files:
+        in_file.close()
+
+    print("Merged  {} bytes".format(total_size))
+
+
+main()