diff --git a/book/build.sh b/book/build.sh
index 14063a5279..ed06ea3055 100755
--- a/book/build.sh
+++ b/book/build.sh
@@ -3,16 +3,4 @@ set -e
 
 cd "$(dirname "$0")"
 
-cargo_install_unless() {
-  declare crate=$1
-  shift
-
-  "$@" > /dev/null 2>&1 || \
-    cargo install "$crate"
-}
-
-export PATH=$CARGO_HOME/bin:$PATH
-cargo_install_unless mdbook mdbook --help
-cargo_install_unless svgbob_cli svgbob --help
-
 make -j"$(nproc)"
diff --git a/ci/audit.sh b/ci/audit.sh
deleted file mode 100755
index e8ff169805..0000000000
--- a/ci/audit.sh
+++ /dev/null
@@ -1,20 +0,0 @@
-#!/usr/bin/env bash
-#
-# Audits project dependencies for security vulnerabilities
-#
-set -e
-
-cd "$(dirname "$0")/.."
-source ci/_
-
-cargo_install_unless() {
-  declare crate=$1
-  shift
-
-  "$@" > /dev/null 2>&1 || \
-    _ cargo install "$crate"
-}
-
-cargo_install_unless cargo-audit cargo audit --version
-
-_ cargo audit
diff --git a/ci/test-checks.sh b/ci/test-checks.sh
index 301c120c62..ddc9e05457 100755
--- a/ci/test-checks.sh
+++ b/ci/test-checks.sh
@@ -12,7 +12,7 @@ export RUSTFLAGS="-D warnings"
 _ cargo +"$rust_stable" fmt --all -- --check
 _ cargo +"$rust_stable" clippy --all -- --version
 _ cargo +"$rust_stable" clippy --all -- --deny=warnings
-_ ci/audit.sh
+_ cargo +"$rust_stable" audit
 _ ci/nits.sh
 _ book/build.sh