diff --git a/setup_board b/setup_board
index c6628f885d..e5b4a4853f 100755
--- a/setup_board
+++ b/setup_board
@@ -235,12 +235,33 @@ sudo_multi "${cmds[@]}"
 
 sudo_clobber "${BOARD_SETUP}" <<EOF
 # Created by setup_board
+
+# Settings derived from the host environment
+CBUILD="$(portageq envvar CHOST)"
+HOSTCC="$(portageq envvar CHOST)-gcc"
+PORTDIR="$(portageq envvar PORTDIR)"
+PORTDIR_OVERLAY="$(portageq envvar PORTDIR_OVERLAY)"
+DISTDIR="$(portageq envvar DISTDIR)"
+MAKEOPTS="$(portageq envvar MAKEOPTS)"
+
+# Board specific settings
 CHOST="${BOARD_CHOST}"
 ROOT="${BOARD_ROOT}/"
-MAKEOPTS="--jobs=${NUM_JOBS} --load-average=$((NUM_JOBS * 2))"
-PKG_CONFIG="pkg-config-${BOARD_VARIANT}"
 BOARD_USE="${BOARD_VARIANT}"
+PKGDIR="${BOARD_ROOT}/var/lib/portage/pkgs"
+PORT_LOGDIR="${BOARD_ROOT}/var/log/portage"
+PORTAGE_TMPDIR="${BOARD_ROOT}/var/tmp"
 PORTAGE_BINHOST="${BOARD_BINHOST}"
+
+# TODO(marineam): Unsure if we need to specify both the pkg-config
+# env variables and a pkg-config wrapper that does the same thing...
+PKG_CONFIG="pkg-config-${BOARD_VARIANT}"
+PKG_CONFIG_PATH="${BOARD_ROOT}/usr/lib/pkgconfig:${BOARD_ROOT}/usr/share/pkgconfig"
+PKG_CONFIG_SYSROOT_DIR="${BOARD_ROOT}"
+
+# Generally there isn't any need to add packages to @world by default.
+# You can use --select to override this.
+EMERGE_DEFAULT_OPTS="--oneshot"
 EOF
 
 generate_all_wrappers