diff --git a/.circleci/config.yml b/.circleci/config.yml
index 805611eb..f3dbf371 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -6,13 +6,13 @@ version: 2.1
 parameters:
     tools-cache-version:
         type: string
-        default: "v7"
+        default: "v8"
 
 # default execution env.s
 executors:
     main-env:
         docker:
-            - image: ucbbar/chipyard-ci-image:ab57b7d
+            - image: ucbbar/chipyard-ci-image:c29770
         environment:
             JVM_OPTS: -Xmx3200m # Customize the JVM maximum heap limit
 
diff --git a/scripts/centos-req.sh b/scripts/centos-req.sh
index 1a1439d1..8c7ac3a0 100755
--- a/scripts/centos-req.sh
+++ b/scripts/centos-req.sh
@@ -4,15 +4,21 @@ set -ex
 
 sudo yum groupinstall -y "Development tools"
 sudo yum install -y gmp-devel mpfr-devel libmpc-devel zlib-devel vim git java java-devel
-curl https://bintray.com/sbt/rpm/rpm | sudo tee /etc/yum.repos.d/bintray-sbt-rpm.repo
+
+# Install SBT https://www.scala-sbt.org/release/docs/Installing-sbt-on-Linux.html#Red+Hat+Enterprise+Linux+and+other+RPM-based+distributions
+# sudo rm -f /etc/yum.repos.d/bintray-rpm.repo
+# Use rm above if sbt installed from bintray before.
+curl -L https://www.scala-sbt.org/sbt-rpm.repo > sbt-rpm.repo
+sudo mv sbt-rpm.repo /etc/yum.repos.d/
+
 sudo yum install -y sbt texinfo gengetopt
 sudo yum install -y expat-devel libusb1-devel ncurses-devel cmake "perl(ExtUtils::MakeMaker)"
 # deps for poky
-sudo yum install -y python36 patch diffstat texi2html texinfo subversion chrpath git wget
+sudo yum install -y python38 patch diffstat texi2html texinfo subversion chrpath git wget
 # deps for qemu
 sudo yum install -y gtk3-devel
 # deps for firemarshal
-sudo yum install -y python36-pip python36-devel rsync libguestfs-tools makeinfo expat ctags
+sudo yum install -y python38-pip python38-devel rsync libguestfs-tools makeinfo expat ctags
 # Install GNU make 4.x (needed to cross-compile glibc 2.28+)
 sudo yum install -y centos-release-scl
 sudo yum install -y devtoolset-8-make
@@ -24,4 +30,4 @@ sudo yum install -y python
 git clone http://git.veripool.org/git/verilator
 cd verilator
 git checkout v4.034
-autoconf && ./configure && make -j16 && sudo make install
+autoconf && ./configure && make -j$(nproc) && sudo make install
diff --git a/scripts/ubuntu-req.sh b/scripts/ubuntu-req.sh
index 4889dc48..ff5fe3ad 100755
--- a/scripts/ubuntu-req.sh
+++ b/scripts/ubuntu-req.sh
@@ -2,21 +2,21 @@
 
 set -ex
 
-sudo apt-get install -y build-essential bison flex software-properties-common
+sudo apt-get install -y build-essential bison flex software-properties-common curl
 sudo apt-get install -y libgmp-dev libmpfr-dev libmpc-dev zlib1g-dev vim default-jdk default-jre
-# install sbt: https://www.scala-sbt.org/release/docs/Installing-sbt-on-Linux.html
-echo "deb https://dl.bintray.com/sbt/debian /" | sudo tee -a /etc/apt/sources.list.d/sbt.list
+# install sbt: https://www.scala-sbt.org/release/docs/Installing-sbt-on-Linux.html#Ubuntu+and+other+Debian-based+distributions
+echo "deb https://repo.scala-sbt.org/scalasbt/debian /" | sudo tee -a /etc/apt/sources.list.d/sbt.list
 curl -sL "https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x2EE0EA64E40A89B84B2DF73499E82A75642AC823" | sudo apt-key add
 sudo apt-get update
 sudo apt-get install -y sbt
 sudo apt-get install -y texinfo gengetopt
 sudo apt-get install -y libexpat1-dev libusb-dev libncurses5-dev cmake
 # deps for poky
-sudo apt-get install -y python3.6 patch diffstat texi2html texinfo subversion chrpath wget
+sudo apt-get install -y python3.8 patch diffstat texi2html texinfo subversion chrpath wget
 # deps for qemu
 sudo apt-get install -y libgtk-3-dev gettext
 # deps for firemarshal
-sudo apt-get install -y python3-pip python3.6-dev rsync libguestfs-tools expat ctags
+sudo apt-get install -y python3-pip python3.8-dev rsync libguestfs-tools expat ctags
 # install DTC
 sudo apt-get install -y device-tree-compiler
 sudo apt-get install -y python
@@ -26,6 +26,7 @@ sudo apt-get update
 sudo apt-get install git -y
 
 # install verilator
+sudo apt-get install -y autoconf
 git clone http://git.veripool.org/git/verilator
 cd verilator
 git checkout v4.034