diff --git a/Dockerfile.custom b/Dockerfile.custom
index e4177c7..a7ab2de 100644
--- a/Dockerfile.custom
+++ b/Dockerfile.custom
@@ -33,9 +33,9 @@ ARG YARN_INSTALL_VERSION
 RUN if [ -n "$NODE_INSTALL_VERSION" ] ; then /scripts/install-node $NODE_INSTALL_VERSION $YARN_INSTALL_VERSION && node --version && yarn --version; fi
 
 # Golang
-ARG GOLANG_VERSION
+ARG INSTALL_GOLANG_VERSION
 ARG GOLANG_DOWNLOAD_SHA256
-RUN if [ -n "$GOLANG_VERSION" ] ; then /scripts/install-golang && go version; fi
+RUN if [ -n "$INSTALL_GOLANG_VERSION" ] ; then /scripts/install-golang "${INSTALL_GOLANG_VERSION}" "${GOLANG_DOWNLOAD_SHA256}" && go version; fi
 
 # Postgres
 # Codedebt: currently this will only install the default version of postgres,
diff --git a/Dockerfile.www-gitlab-com b/Dockerfile.www-gitlab-com
index 8307459..bc391ac 100644
--- a/Dockerfile.www-gitlab-com
+++ b/Dockerfile.www-gitlab-com
@@ -1,7 +1,5 @@
 FROM ruby:2.3-slim
 
-ENV PACKAGES="git-core pandoc texlive-latex-recommended texlive-xetex texlive-fonts-recommended lmodern ed file curl"
-
 ADD / /
 RUN /scripts/install-www-gitlab-com
 
diff --git a/scripts/custom-docker-build b/scripts/custom-docker-build
index af59b81..fadaa3e 100755
--- a/scripts/custom-docker-build
+++ b/scripts/custom-docker-build
@@ -7,17 +7,17 @@ function print_golang_args() {
 
     case "$1" in
         1.8)
-            GOLANG_VERSION=1.8
+            INSTALL_GOLANG_VERSION=1.8
             GOLANG_DOWNLOAD_SHA256=253ab94104ee3923e228a2cb2116e5e462ad3ebaeea06ff04463479d7f12d27ca
             ;;
         1.9)
-            GOLANG_VERSION=1.9.2
+            INSTALL_GOLANG_VERSION=1.9.2
             GOLANG_DOWNLOAD_SHA256=de874549d9a8d8d8062be05808509c09a88a248e77ec14eb77453530829ac02b
             ;;
         *) echo "Unknown golang version $1"; exit 1;
     esac
 
-    printf -- "--build-arg GOLANG_VERSION=%s " "$GOLANG_VERSION"
+    printf -- "--build-arg INSTALL_GOLANG_VERSION=%s " "$INSTALL_GOLANG_VERSION"
     printf -- "--build-arg GOLANG_DOWNLOAD_SHA256=%s " "$GOLANG_DOWNLOAD_SHA256"
 }
 
diff --git a/scripts/install-chrome b/scripts/install-chrome
index 3ad988c..044a6c1 100755
--- a/scripts/install-chrome
+++ b/scripts/install-chrome
@@ -1,8 +1,10 @@
 #!/bin/bash
 
-set -xeo pipefail
+set -xeuo pipefail
+IFS=$'\n\t'
 
 CHROME_VERSION=${1:-60.0.3112.90-1}
+export DEBIAN_FRONTEND=noninteractive
 
 curl -sS -L https://dl.google.com/linux/linux_signing_key.pub | apt-key add -
 echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" > /etc/apt/sources.list.d/google.list
diff --git a/scripts/install-essentials b/scripts/install-essentials
index ffbf14e..2df4a5a 100755
--- a/scripts/install-essentials
+++ b/scripts/install-essentials
@@ -1,6 +1,9 @@
 #!/bin/bash
 
-set -xeo pipefail
+set -xeuo pipefail
+IFS=$'\n\t'
+
+export DEBIAN_FRONTEND=noninteractive
 
 apt-get update
 apt-get install -y \
diff --git a/scripts/install-git b/scripts/install-git
index 7231150..109fc2d 100755
--- a/scripts/install-git
+++ b/scripts/install-git
@@ -1,4 +1,7 @@
-#!/bin/sh
+#!/bin/bash
+
+set -xeuo pipefail
+IFS=$'\n\t'
 
 mkdir build \
 	&& curl -fsSL "$GIT_DOWNLOAD_URL" -o git.tar.gz \
diff --git a/scripts/install-golang b/scripts/install-golang
index 74b86f8..25532b8 100755
--- a/scripts/install-golang
+++ b/scripts/install-golang
@@ -1,10 +1,13 @@
 #!/bin/bash
 
-GOLANG_VERSION=${1:-1.8}
-GOLANG_DOWNLOAD_URL="https://golang.org/dl/go$GOLANG_VERSION.linux-amd64.tar.gz"
-GOLANG_DOWNLOAD_SHA256=${2:-53ab94104ee3923e228a2cb2116e5e462ad3ebaeea06ff04463479d7f12d27ca}
+set -xeou pipefail
 
-curl -fsSL "$GOLANG_DOWNLOAD_URL" -o golang.tar.gz \
-	&& echo "$GOLANG_DOWNLOAD_SHA256  golang.tar.gz" | sha256sum -c - \
-	&& tar -C /usr/local -xzf golang.tar.gz \
-	&& rm golang.tar.gz
+INSTALL_GOLANG_VERSION=${1}
+GOLANG_DOWNLOAD_SHA256=${2}
+
+GOLANG_DOWNLOAD_URL="https://golang.org/dl/go${INSTALL_GOLANG_VERSION}.linux-amd64.tar.gz"
+
+curl -fsSL "$GOLANG_DOWNLOAD_URL" -o golang.tar.gz
+echo "${GOLANG_DOWNLOAD_SHA256}  golang.tar.gz" | sha256sum -c -
+tar -C /usr/local -xzf golang.tar.gz
+rm golang.tar.gz
diff --git a/scripts/install-node b/scripts/install-node
index da509a3..d317050 100755
--- a/scripts/install-node
+++ b/scripts/install-node
@@ -1,6 +1,6 @@
 #!/bin/bash
-
-set -xeo pipefail
+set -xeuo pipefail
+IFS=$'\n\t'
 
 NODE_INSTALL_VERSION=${1:-7.x}
 YARN_INSTALL_VERSION=${2:-0.27.5-1}
diff --git a/scripts/install-postgresql b/scripts/install-postgresql
index faef1c0..826edad 100755
--- a/scripts/install-postgresql
+++ b/scripts/install-postgresql
@@ -1,10 +1,12 @@
 #!/bin/bash
+set -xeuo pipefail
+IFS=$'\n\t'
 
-set -xeo pipefail
+export DEBIAN_FRONTEND=noninteractive
 
 curl -sS -L https://www.postgresql.org/media/keys/ACCC4CF8.asc | apt-key add -
 echo "deb http://apt.postgresql.org/pub/repos/apt/ xenial-pgdg main" | tee /etc/apt/sources.list.d/postgresql.list
 
 apt-get update
-env DEBIAN_FRONTEND="noninteractive" apt-get install -y postgresql-client
+apt-get install -y postgresql-client
 apt-get autoremove -yq
diff --git a/scripts/install-ruby b/scripts/install-ruby
index 3ebeaf3..7aa1212 100755
--- a/scripts/install-ruby
+++ b/scripts/install-ruby
@@ -1,6 +1,6 @@
 #!/bin/bash
-
-set -xeo pipefail
+set -xeuo pipefail
+IFS=$'\n\t'
 
 cd /tmp
 wget http://cache.ruby-lang.org/pub/ruby/2.2/ruby-2.2.2.tar.gz
diff --git a/scripts/install-www-gitlab-com b/scripts/install-www-gitlab-com
index 3593997..cea7788 100755
--- a/scripts/install-www-gitlab-com
+++ b/scripts/install-www-gitlab-com
@@ -1,11 +1,15 @@
 #!/bin/bash
 
-set -xeo pipefail
+set -xeuo pipefail
+IFS=$'\n\t'
+
+export DEBIAN_FRONTEND=noninteractive
 
 apt-get update
 apt-get install -yq --no-install-recommends \
   make gcc g++ locales \
-  $PACKAGES
+  git-core pandoc texlive-latex-recommended texlive-xetex \
+  texlive-fonts-recommended lmodern ed file curl
 
 apt-get autoremove -yq