diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index f290efb..80999ce 100755
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -1,58 +1,79 @@
-#!/bin/bash
+#!/usr/bin/env bash
+set -e
 
-# Backwards compatibility for old variable names (deprecated)
-if [ "x$PGUSER"     != "x" ]; then
-    POSTGRES_USER=$PGUSER
-fi
-if [ "x$PGPASSWORD" != "x" ]; then
-    POSTGRES_PASSWORD=$PGPASSWORD
-fi
+# usage: file_env VAR [DEFAULT]
+#    ie: file_env 'XYZ_DB_PASSWORD' 'example'
+# (will allow for "$XYZ_DB_PASSWORD_FILE" to fill in the value of
+#  "$XYZ_DB_PASSWORD" from a file, especially for Docker's secrets feature)
+file_env() {
+	local var="$1"
+	local fileVar="${var}_FILE"
+	local def="${2:-}"
+	if [ "${!var:-}" ] && [ "${!fileVar:-}" ]; then
+		echo >&2 "error: both $var and $fileVar are set (but are exclusive)"
+		exit 1
+	fi
+	local val="$def"
+	if [ "${!var:-}" ]; then
+		val="${!var}"
+	elif [ "${!fileVar:-}" ]; then
+		val="$(< "${!fileVar}")"
+	fi
+	export "$var"="$val"
+	unset "$fileVar"
+}
 
-# Forwards-compatibility for old variable names (pg_basebackup uses them)
-if [ "x$PGPASSWORD" = "x" ]; then
-    export PGPASSWORD=$POSTGRES_PASSWORD
+if [ "${1:0:1}" = '-' ]; then
+	set -- postgres "$@"
 fi
 
-# Based on official postgres package's entrypoint script (https://hub.docker.com/_/postgres/)
-# Modified to be able to set up a slave. The docker-entrypoint-initdb.d hook provided is inadequate.
+# allow the container to be started with `--user`
+if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
+	mkdir -p "$PGDATA"
+	chown -R postgres "$PGDATA"
+	chmod 700 "$PGDATA"
 
-set -e
+	mkdir -p /var/run/postgresql
+	chown -R postgres /var/run/postgresql
+	chmod 775 /var/run/postgresql
 
-if [ "${1:0:1}" = '-' ]; then
-	set -- postgres "$@"
+	# Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+	if [ "$POSTGRES_INITDB_XLOGDIR" ]; then
+		mkdir -p "$POSTGRES_INITDB_XLOGDIR"
+		chown -R postgres "$POSTGRES_INITDB_XLOGDIR"
+		chmod 700 "$POSTGRES_INITDB_XLOGDIR"
+	fi
+
+	exec gosu postgres "$BASH_SOURCE" "$@"
 fi
 
 if [ "$1" = 'postgres' ]; then
 	mkdir -p "$PGDATA"
-	chmod 700 "$PGDATA"
-	chown -R postgres "$PGDATA"
-
-	mkdir -p /run/postgresql
-	chmod g+s /run/postgresql
-	chown -R postgres /run/postgresql
+	chown -R "$(id -u)" "$PGDATA" 2>/dev/null || :
+	chmod 700 "$PGDATA" 2>/dev/null || :
 
 	# look specifically for PG_VERSION, as it is expected in the DB dir
 	if [ ! -s "$PGDATA/PG_VERSION" ]; then
-	    if [ "x$REPLICATE_FROM" == "x" ]; then
-		eval "gosu postgres initdb $POSTGRES_INITDB_ARGS"
-	    else
-            	until ping -c 1 -W 1 ${REPLICATE_FROM}
-            	do
-                	echo "Waiting for master to ping..."
-                	sleep 1s
-            	done
-            	until gosu postgres pg_basebackup -h ${REPLICATE_FROM} -D ${PGDATA} -U ${POSTGRES_USER} -vP -w
-            	do
-                	echo "Waiting for master to connect..."
-                	sleep 1s
-            	done
+		file_env 'POSTGRES_INITDB_ARGS'
+		if [ "$POSTGRES_INITDB_XLOGDIR" ]; then
+            export POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_INITDB_XLOGDIR"
+		fi
+
+        if [ "x$REPLICATE_FROM" == "x" ]; then
+            eval "initdb --username=postgres $POSTGRES_INITDB_ARGS"
 	    fi
 
 		# check password first so we can output the warning before postgres
 		# messes it up
+		file_env 'POSTGRES_PASSWORD'
 		if [ "$POSTGRES_PASSWORD" ]; then
 			pass="PASSWORD '$POSTGRES_PASSWORD'"
 			authMethod=md5
+
+			# Forwards-compatibility for old variable names (pg_basebackup uses them)
+            if [ "x$PGPASSWORD" = "x" ]; then
+                export PGPASSWORD=$POSTGRES_PASSWORD
+            fi
 		else
 			# The - option suppresses leading tabs but *not* spaces. :)
 			cat >&2 <<-'EOWARN'
@@ -73,20 +94,35 @@ if [ "$1" = 'postgres' ]; then
 			authMethod=trust
 		fi
 
-		if [ "x$REPLICATE_FROM" == "x" ]; then
+        if [ "x$REPLICATE_FROM" == "x" ]; then
+            true # Do nothing
+	    else
+            until ping -c 1 -W 1 ${REPLICATE_FROM}
+            do
+                echo "Waiting for master to ping..."
+                sleep 1s
+            done
+            until pg_basebackup -h ${REPLICATE_FROM} -D ${PGDATA} -U ${POSTGRES_USER} -vP -w
+            do
+                echo "Waiting for master to connect..."
+                sleep 1s
+            done
+	    fi
+
+        if [ "x$REPLICATE_FROM" == "x" ]; then
 
-		{ echo; echo "host replication all 0.0.0.0/0 $authMethod"; } | gosu postgres tee -a "$PGDATA/pg_hba.conf" > /dev/null
-		{ echo; echo "host all all 0.0.0.0/0 $authMethod"; } | gosu postgres tee -a "$PGDATA/pg_hba.conf" > /dev/null
+        { echo; echo "host replication all 0.0.0.0/0 $authMethod"; } >> "$PGDATA/pg_hba.conf"
+		{ echo; echo "host all all 0.0.0.0/0 $authMethod"; } >> "$PGDATA/pg_hba.conf"
 
-		# internal start of server in order to allow set-up using psql-client		
+		# internal start of server in order to allow set-up using psql-client
 		# does not listen on external TCP/IP and waits until start finishes
-		gosu postgres pg_ctl -D "$PGDATA" \
+		PGUSER="${PGUSER:-postgres}" \
+		pg_ctl -D "$PGDATA" \
 			-o "-c listen_addresses='localhost'" \
 			-w start
 
-		: ${POSTGRES_USER:=postgres}
-		: ${POSTGRES_DB:=$POSTGRES_USER}
-		export POSTGRES_USER POSTGRES_DB
+		file_env 'POSTGRES_USER' 'postgres'
+		file_env 'POSTGRES_DB' "$POSTGRES_USER"
 
 		psql=( psql -v ON_ERROR_STOP=1 )
 
@@ -106,8 +142,8 @@ if [ "$1" = 'postgres' ]; then
 			$op USER "$POSTGRES_USER" WITH SUPERUSER $pass ;
 		EOSQL
 		echo
-		
-		fi
+
+        fi
 
 		psql+=( --username "$POSTGRES_USER" --dbname "$POSTGRES_DB" )
 
@@ -115,23 +151,22 @@ if [ "$1" = 'postgres' ]; then
 		for f in /docker-entrypoint-initdb.d/*; do
 			case "$f" in
 				*.sh)     echo "$0: running $f"; . "$f" ;;
-				*.sql)    echo "$0: running $f"; "${psql[@]}" < "$f"; echo ;;
+				*.sql)    echo "$0: running $f"; "${psql[@]}" -f "$f"; echo ;;
 				*.sql.gz) echo "$0: running $f"; gunzip -c "$f" | "${psql[@]}"; echo ;;
 				*)        echo "$0: ignoring $f" ;;
 			esac
 			echo
 		done
 
-	if [ "x$REPLICATE_FROM" == "x" ]; then
-		gosu postgres pg_ctl -D "$PGDATA" -m fast -w stop
-	fi
+        if [ "x$REPLICATE_FROM" == "x" ]; then
+            PGUSER="${PGUSER:-postgres}" \
+		    pg_ctl -D "$PGDATA" -m fast -w stop
+	    fi
 
 		echo
 		echo 'PostgreSQL init process complete; ready for start up.'
 		echo
 	fi
-
-	exec gosu postgres "$@"
 fi
 
 exec "$@"