diff --git a/cdk/orchestrator-job.Dockerfile b/cdk/orchestrator-job.Dockerfile
index de9a76a..d26f1e3 100644
--- a/cdk/orchestrator-job.Dockerfile
+++ b/cdk/orchestrator-job.Dockerfile
@@ -1,4 +1,4 @@
-from amazonlinux:2023
+FROM amazonlinux:2023
 
 RUN dnf install -y python3-pip \
     && python3 -m pip install boto3
diff --git a/cdk/per-instance-job.Dockerfile b/cdk/per-instance-job.Dockerfile
index cd8a7a3..548d74f 100644
--- a/cdk/per-instance-job.Dockerfile
+++ b/cdk/per-instance-job.Dockerfile
@@ -1,7 +1,12 @@
-from amazonlinux:2023
+FROM amazonlinux:2023
 
 RUN dnf install -y git
 
+# Installing rustup is a pain, because you need to modify the shell afterwards.
+# Easier to just do it here, vs later via install-tools-AL2023.py
+RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+ENV PATH="/root/.cargo/bin:${PATH}"
+
 # s3_benchmarks/__init__.py is shared by CDK Stack and Batch jobs
 COPY s3_benchmarks/__init__.py /s3_benchmarks/
 
diff --git a/runners/s3-benchrunner-rust/Cargo.toml b/runners/s3-benchrunner-rust/Cargo.toml
index d945483..e229bf8 100644
--- a/runners/s3-benchrunner-rust/Cargo.toml
+++ b/runners/s3-benchrunner-rust/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2021"
 [dependencies]
 
 # Swap which line is commented-out to use GitHub or local aws-s3-transfer-manager
-aws-s3-transfer-manager = { git = "https://github.com/awslabs/aws-s3-transfer-manager-rs.git", rev = "9f16242e5a2a0c9d1fcc2b4d1006fb01c9c551f2" }
+aws-s3-transfer-manager = { git = "https://github.com/awslabs/aws-s3-transfer-manager-rs.git", rev = "3dd20c8aa0872352100cf456beee02bfc53c73d1" }
 # aws-s3-transfer-manager = { path = "../../../aws-s3-transfer-manager-rs/aws-s3-transfer-manager" }
 
 # tracing-opentelemetry 0.26.0 is a bit broken (see https://github.com/tokio-rs/tracing-opentelemetry/issues/159)
diff --git a/scripts/install-tools-AL2023.py b/scripts/install-tools-AL2023.py
index 1032f09..fb379e4 100755
--- a/scripts/install-tools-AL2023.py
+++ b/scripts/install-tools-AL2023.py
@@ -1,7 +1,5 @@
 #!/usr/bin/env python3
 import argparse
-import os
-import os.path
 import shutil
 import urllib.request
 
@@ -31,16 +29,12 @@
      'python3-devel',  # for building aws-crt-python
      ])
 
-# install rust via rustup.sh
-# (the version in dnf is too old, in July 2024 it was the 1+ year old rust 1.68)
-# do NOT use sudo with rustup
-rustup_url = 'https://sh.rustup.rs'
-rustup_filepath = '/tmp/rustup.sh'
-print(f'downloading: {rustup_url} -> {rustup_filepath} ...')
-urllib.request.urlretrieve(rustup_url, rustup_filepath)
-run(['sh', rustup_filepath, '-y'])
-
-# add rust to path, so current process can run it without reloading shell
-PATH = os.environ['PATH']
-if '.cargo/bin' not in PATH:
-    os.environ['PATH'] = f"{PATH}:{os.path.expanduser('~/.cargo/bin')}"
+if not shutil.which('cargo'):
+    # install rust via rustup.sh
+    # (the version in dnf is too old, in July 2024 it was the 1+ year old rust 1.68)
+    # do NOT use sudo with rustup
+    rustup_url = 'https://sh.rustup.rs'
+    rustup_filepath = '/tmp/rustup.sh'
+    print(f'downloading: {rustup_url} -> {rustup_filepath} ...')
+    urllib.request.urlretrieve(rustup_url, rustup_filepath)
+    run(['sh', rustup_filepath, '-y'])