diff --git a/engine/src/flutter/ci/check_roll.sh b/engine/src/flutter/ci/check_roll.sh
deleted file mode 100755
index ffb2cca972..0000000000
--- a/engine/src/flutter/ci/check_roll.sh
+++ /dev/null
@@ -1,52 +0,0 @@
-#!/bin/bash
-#
-# Copyright 2013 The Flutter Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-set -e
-
-# Needed because if it is set, cd may print the path it changed to.
-unset CDPATH
-
-# On Mac OS, readlink -f doesn't work, so follow_links traverses the path one
-# link at a time, and then cds into the link destination and find out where it
-# ends up.
-#
-# The function is enclosed in a subshell to avoid changing the working directory
-# of the caller.
-function follow_links() (
-  cd -P "$(dirname -- "$1")"
-  file="$PWD/$(basename -- "$1")"
-  while [[ -h "$file" ]]; do
-    cd -P "$(dirname -- "$file")"
-    file="$(readlink -- "$file")"
-    cd -P "$(dirname -- "$file")"
-    file="$PWD/$(basename -- "$file")"
-  done
-  echo "$file"
-)
-
-SCRIPT_DIR=$(follow_links "$(dirname -- "${BASH_SOURCE[0]}")")
-FLUTTER_DIR="$(cd "$SCRIPT_DIR/.."; pwd -P)"
-
-cd "$FLUTTER_DIR"
-
-if git remote get-url upstream >/dev/null 2>&1; then
-  UPSTREAM=upstream/master
-else
-  UPSTREAM=master
-fi;
-
-FLUTTER_VERSION="$(curl -s https://raw.githubusercontent.com/flutter/flutter/master/bin/internal/engine.version)"
-BEHIND="$(git rev-list "$FLUTTER_VERSION".."$UPSTREAM" --oneline | wc -l)"
-MAX_BEHIND=16 # no more than 4 bisections to identify the issue
-
-if [[ $BEHIND -le $MAX_BEHIND ]]; then
-  echo "OK, the flutter/engine to flutter/flutter roll is only $BEHIND commits behind."
-else
-  echo "ERROR: The flutter/engine to flutter/flutter roll is $BEHIND commits behind!"
-  echo "       It exceeds our max allowance of $MAX_BEHIND. Unless that this commit fixes the roll,"
-  echo "       please roll engine into flutter first before merging more commits into engine."
-  exit 1
-fi
diff --git a/engine/src/flutter/ci/docker/windows_build/prepare_windows_server_2016_core.ps1 b/engine/src/flutter/ci/docker/windows_build/prepare_windows_server_2016_core.ps1
deleted file mode 100644
index 69a4d2753c..0000000000
--- a/engine/src/flutter/ci/docker/windows_build/prepare_windows_server_2016_core.ps1
+++ /dev/null
@@ -1,68 +0,0 @@
-# The following powershell script prepares the VM image
-# flutter-engine-windows-server-2016 used by Flutter engine's
-# build_windows presubmit tests (see .cirrus.yml).
-#
-# The exact step of generating the VM image is:
-# 1. Create a "Windows Server 2016 Datacenter Core" GCE instance with 50GB disk
-# 2. RDP into that GCE instance to run this script with powershell
-#    (e.g., `powershell -File prepare_windows_server_2016_core.ps1`)
-# 3. Shutdown the instance and take an image of that instance
-#
-# Note that ` is the escape character in powershell.
-
-# Install visual studio 2017
-curl https://aka.ms/vs/15/release/vs_community.exe -o vs_community.exe
-./vs_community.exe --passive --wait `
-    --add Microsoft.VisualStudio.Workload.NativeCrossPlat `
-    --add Microsoft.VisualStudio.Workload.NativeDesktop --includeRecommended
-
-# Install debugger tools
-curl https://download.microsoft.com/download/5/C/3/5C3770A3-12B4-4DB4-BAE7-99C624EB32AD/windowssdk/winsdksetup.exe `
-    -o winsdksetup.exe
-./winsdksetup.exe /features OptionId.WindowsDesktopDebuggers /q
-
-# Download depot tools
-curl https://storage.googleapis.com/chrome-infra/depot_tools.zip `
-    -o depot_tools.zip
-Expand-Archive -LiteralPath depot_tools.zip -DestinationPath c:/depot_tools
-
-# Download git. Although depot_tools has its own git.bat, this is needed for
-# Flutter engine's gn to run correctly.
-#
-# Somehow, curl can't get the MinGit from github. Fortunately, taobo works.
-curl https://npm.taobao.org/mirrors/git-for-windows/v2.21.0.windows.1/MinGit-2.21.0-64-bit.zip `
-    -o MinGit.zip
-Expand-Archive -LiteralPath MinGit.zip -DestinationPath c:/MinGit
-
-# Restarting the terminal (or even the whole VM) is required to let following
-# environment variables to take effect.
-setx path "c:/depot_tools/;c:/MinGit/cmd;${env:path}"
-setx DEPOT_TOOLS_WIN_TOOLCHAIN 0
-setx GYP_MSVS_OVERRIDE_PATH "c:/Program Files (x86)/Microsoft Visual Studio/2017/Community"
-
-mkdir c:/flutter/engine
-curl https://raw.githubusercontent.com/flutter/engine/main/ci/docker/build/engine_gclient `
-    -o c:/flutter/engine/.gclient
-
-# Once the above script finishes successfully, one can make an image of the VM
-# for the CI test.
-#
-# For sanity check, one can also test the VM to make sure that Flutter engine
-# can be built in that VM. (The test is optional and our current image is made
-# before doing these tests. We only did a reboot before making that image to
-# ensure environment variables are loaded. However, Cirrus CI seems to have
-# problems reading those environment variables so we ended up setting them in
-# ".cirrus.yml" manually.)
-#
-# To test, first reboot of the terminal (or VM) to ensure that environment
-# variables "path", "DEPOT_TOOLS_WIN_TOOLCHAIN", and "GYP_MSVS_OVERRIDE_PATH"
-# are set. (Those environment variables are not needed for Cirrus CI as Cirrus
-# sets those environment variables by itself.)
-#
-# After all the environment variables above are loaded correctly, one may test
-# build the engine by:
-#   cd c:/flutter/engine
-#   gclient sync
-#   cd src
-#   python flutter/tools/gn
-#   ninja -C out/host_debug