diff --git a/build/Jenkinsfile.pr b/build/Jenkinsfile.pr
index 144441613e..414db896ca 100644
--- a/build/Jenkinsfile.pr
+++ b/build/Jenkinsfile.pr
@@ -14,7 +14,7 @@ pipeline {
     options { buildDiscarder(logRotator(numToKeepStr: '3')) }
 
     environment {
-        DCNAME = "${rnd}"
+        COMPOSE_PROJECT_NAME="${rnd}-${env.BUILD_NUMBER}"
     }
 
     stages {
@@ -54,13 +54,13 @@ pipeline {
                         ansiColor('xterm') {
                             sh """
                                 #!/bin/bash -ex
-                                git checkout $env.BRANCH_NAME || git checkout $env.CHANGE_BRANCH || git checkout $env.GIT_BRANCH || git checkout master || echo 1
+                                git checkout $env.BRANCH_NAME || git checkout $env.CHANGE_BRANCH || git checkout $env.GIT_BRANCH || git checkout master
                                 rm -rf ./dist
                                 export WEBAPP_GIT_COMMIT=\$(git rev-parse HEAD)
 
                                 echo Webapp Commit: \${WEBAPP_GIT_COMMIT}
 
-                                curl -f -o ./dist.tar.gz https://releases.mattermost.com/mattermost-webapp/commit/\${WEBAPP_GIT_COMMIT}/mattermost-webapp.tar.gz && mkdir ./dist && tar -xvf ./dist.tar.gz -C ./dist --strip-components=1 || make node_modules test build || exit 1
+                                curl -f -o ./dist.tar.gz https://releases.mattermost.com/mattermost-webapp/commit/\${WEBAPP_GIT_COMMIT}/mattermost-webapp.tar.gz && mkdir ./dist && tar -xvf ./dist.tar.gz -C ./dist --strip-components=1 || make node_modules test build
                             """
                         }
                     }
@@ -79,9 +79,9 @@ pipeline {
                         sh """
                             cd /go/src/github.com/mattermost/mattermost-server
                             mv config/default.json config/config.json || echo ""
-                            make check-style BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}' || exit 1
-                            make build BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}' || exit 1
-                            make package BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}' || exit 1
+                            make check-style BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}'
+                            make build BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}'
+                            make package BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}'
                         """
                     }
                 }
@@ -101,41 +101,38 @@ pipeline {
                 CI_INBUCKET_SMTP_PORT = "10025"
                 CI_LDAP_HOST = "openldap"
                 IS_CI = true
+                MM_SQLSETTINGS_DATASOURCE = "mmuser:mostest@tcp(mysql:3306)/mattermost_test?charset=utf8mb4,utf8"
+                MM_EMAILSETTINGS_SMTPSERVER = "inbucket"
+                MM_EMAILSETTINGS_SMTPPORT = "10025"
+                MM_ELASTICSEARCHSETTINGS_CONNECTIONURL = "http://elasticsearch:9200"
             }
 
             steps {
                 dir('src/github.com/mattermost/mattermost-server/build') {
                     ansiColor('xterm') {
                         sh """
-                            COMPOSE_PROJECT_NAME=${DCNAME}-${env.BUILD_NUMBER} docker-compose run --rm start_dependencies
-                            COMPOSE_PROJECT_NAME=${DCNAME}-${env.BUILD_NUMBER} docker-compose up -d mysql postgres minio inbucket openldap elasticsearch redis
+                            docker-compose --no-ansi run --rm start_dependencies
+                            docker-compose --no-ansi ps
 
-                            docker ps
-
-                            docker exec -t openldap-${DCNAME}-${env.BUILD_NUMBER} bash -c 'echo -e "dn: ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: organizationalunit" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
-                            docker exec -t openldap-${DCNAME}-${env.BUILD_NUMBER} bash -c 'echo -e "dn: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test1\nmail: success+testone@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
-                            docker exec -t openldap-${DCNAME}-${env.BUILD_NUMBER} bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" -w mostest';
-                            docker exec -t openldap-${DCNAME}-${env.BUILD_NUMBER} bash -c 'echo -e "dn: uid=test.two,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test2\nmail: success+testtwo@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
-                            docker exec -t openldap-${DCNAME}-${env.BUILD_NUMBER} bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.two,ou=testusers,dc=mm,dc=test,dc=com" -w mostest';
-                            docker exec -t openldap-${DCNAME}-${env.BUILD_NUMBER} bash -c 'echo -e "dn: cn=tgroup,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: groupOfUniqueNames\nuniqueMember: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
+                            docker-compose --no-ansi exec -T openldap bash -c 'echo -e "dn: ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: organizationalunit" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
+                            docker-compose --no-ansi exec -T openldap bash -c 'echo -e "dn: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test1\nmail: success+testone@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
+                            docker-compose --no-ansi exec -T openldap bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" -w mostest';
+                            docker-compose --no-ansi exec -T openldap bash -c 'echo -e "dn: uid=test.two,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test2\nmail: success+testtwo@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
+                            docker-compose --no-ansi exec -T openldap bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.two,ou=testusers,dc=mm,dc=test,dc=com" -w mostest';
+                            docker-compose --no-ansi exec -T openldap bash -c 'echo -e "dn: cn=tgroup,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: groupOfUniqueNames\nuniqueMember: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest';
                         """
                     }
                 }
 
-                withDockerContainer(args: "-u root --privileged --net ${DCNAME}-${BUILD_NUMBER}_mm-test -v ${WORKSPACE}/src:/go/src/", image: 'mattermost/mattermost-build-server:dec-7-2018') {
+                withDockerContainer(args: "-u root --privileged --net ${COMPOSE_PROJECT_NAME}_mm-test -v ${WORKSPACE}/src:/go/src/", image: 'mattermost/mattermost-build-server:dec-7-2018') {
                     ansiColor('xterm') {
                     sh """
                             cd /go/src/github.com/mattermost/mattermost-server
 
-                            sed -i'.bak' 's|mmuser:mostest@tcp(dockerhost:3306)/mattermost_test?charset=utf8mb4,utf8|mmuser:mostest@tcp(mysql:3306)/mattermost_test?charset=utf8mb4,utf8|g' config/config.json;
-                            sed -i'.bak' 's|"SMTPServer": "dockerhost",|"SMTPServer": "inbucket",|g' config/config.json;
-                            sed -i'.bak' 's|"SMTPPort": "2500",|"SMTPPort": "10025",|g' config/config.json;
-                            sed -i'.bak' 's|"ConnectionUrl": "http://dockerhost:9200",|"ConnectionUrl": "http://elasticsearch:9200",|g' config/config.json;
                             mkdir -p client/plugins
-
                             cat config/config.json
 
-                            make test-server BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}' TESTFLAGS= TESTFLAGSEE= || exit 1
+                            make test-server BUILD_NUMBER='${BRANCH_NAME}-${BUILD_NUMBER}' TESTFLAGS= TESTFLAGSEE=
                         """
                     }
                 }
@@ -234,7 +231,7 @@ pipeline {
             dir('src/github.com/mattermost/mattermost-server/build') {
                 ansiColor('xterm') {
                     sh """
-                        COMPOSE_PROJECT_NAME=${DCNAME}-${env.BUILD_NUMBER} docker-compose down -v
+                        docker-compose --no-ansi down -v
                     """
                 }
             }
diff --git a/build/docker-compose.yml b/build/docker-compose.yml
index 75483d5cc5..6aa47e1767 100644
--- a/build/docker-compose.yml
+++ b/build/docker-compose.yml
@@ -3,7 +3,6 @@ services:
   mysql:
     image: "mysql:5.7"
     restart: always
-    container_name: mysql-$DCNAME-$BUILD_NUMBER
     networks:
       - mm-test
     environment:
@@ -12,20 +11,22 @@ services:
       MYSQL_PASSWORD: mostest
       MYSQL_USER: mmuser
       MYSQL_DATABASE: mattermost_test
+    tmpfs: /var/lib/mysql
+    volumes:
+     - "./docker/mysql.conf.d:/etc/mysql/conf.d"
   postgres:
     image: "postgres:9.4"
     restart: always
-    container_name: postgres-$DCNAME-$BUILD_NUMBER
     networks:
       - mm-test
     environment:
       POSTGRES_USER: mmuser
       POSTGRES_PASSWORD: mostest
       POSTGRES_DB: mattermost_test
+    tmpfs: /var/lib/postgresql/data
   minio:
     image: "minio/minio:RELEASE.2018-05-25T19-49-13Z"
     command: "server /data"
-    container_name: minio-$DCNAME-$BUILD_NUMBER
     networks:
       - mm-test
     environment:
@@ -34,13 +35,11 @@ services:
   inbucket:
     image: "jhillyerd/inbucket:release-1.2.0"
     restart: always
-    container_name: inbucket-$DCNAME-$BUILD_NUMBER
     networks:
       - mm-test
   openldap:
     image: "osixia/openldap:1.1.6"
     restart: always
-    container_name: openldap-$DCNAME-$BUILD_NUMBER
     networks:
       - mm-test
     environment:
@@ -50,7 +49,6 @@ services:
       LDAP_ADMIN_PASSWORD: "mostest"
   elasticsearch:
     image: "mattermost/mattermost-elasticsearch-docker:6.5.1"
-    container_name: elasticsearch-$DCNAME-$BUILD_NUMBER
     networks:
       - mm-test
     environment:
@@ -61,7 +59,6 @@ services:
     image: redis
     networks:
       - mm-test
-    container_name: redis-$DCNAME-$BUILD_NUMBER
 
   start_dependencies:
     image: mattermost/mattermost-wait-for-dep:latest
diff --git a/build/docker/mysql.conf.d/custom.cnf b/build/docker/mysql.conf.d/custom.cnf
new file mode 100644
index 0000000000..27722b73d8
--- /dev/null
+++ b/build/docker/mysql.conf.d/custom.cnf
@@ -0,0 +1,19 @@
+[mysqld]
+bind-address = 0.0.0.0
+
+log-output = NONE
+slow-query-log = 0
+innodb_flush_log_at_trx_commit = 2
+innodb_flush_method = nosync
+innodb_lock_wait_timeout = 50
+innodb_log_buffer_size = 3M
+innodb_buffer_pool_size = 180M
+
+max_connect_errors = 1000000
+max_connections = 900
+
+character-set-server = utf8
+sql_mode = ""
+innodb = FORCE
+default-storage-engine = InnoDB
+max_allowed_packet = 256M
diff --git a/build/local-test-env.sh b/build/local-test-env.sh
index 0cb14527b7..e895bf8788 100755
--- a/build/local-test-env.sh
+++ b/build/local-test-env.sh
@@ -1,7 +1,6 @@
 #!/bin/bash
 
-export DCNAME=localdev
-export BUILD_NUMBER=null
+export COMPOSE_PROJECT_NAME=localdev
 local_cmdname=${0##*/}
 
 usage()
@@ -15,50 +14,41 @@ USAGE
 
 up()
 {
-  COMPOSE_PROJECT_NAME=$DCNAME-$BUILD_NUMBER docker-compose run --rm start_dependencies
-  COMPOSE_PROJECT_NAME=$DCNAME-$BUILD_NUMBER docker-compose up -d mysql postgres minio inbucket openldap elasticsearch redis
+    docker-compose run --rm start_dependencies
 
-  docker exec -t openldap-$DCNAME-$BUILD_NUMBER bash -c 'echo -e "dn: ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: organizationalunit" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
-  docker exec -t openldap-$DCNAME-$BUILD_NUMBER bash -c 'echo -e "dn: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test1\nmail: success+testone@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
-  docker exec -t openldap-$DCNAME-$BUILD_NUMBER bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" -w mostest'
-  docker exec -t openldap-$DCNAME-$BUILD_NUMBER bash -c 'echo -e "dn: uid=test.two,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test2\nmail: success+testtwo@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
-  docker exec -t openldap-$DCNAME-$BUILD_NUMBER bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.two,ou=testusers,dc=mm,dc=test,dc=com" -w mostest'
-  docker exec -t openldap-$DCNAME-$BUILD_NUMBER bash -c 'echo -e "dn: cn=tgroup,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: groupOfUniqueNames\nuniqueMember: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
+    docker-compose exec openldap bash -c 'echo -e "dn: ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: organizationalunit" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
+    docker-compose exec openldap bash -c 'echo -e "dn: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test1\nmail: success+testone@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
+    docker-compose exec openldap bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" -w mostest'
+    docker-compose exec openldap bash -c 'echo -e "dn: uid=test.two,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: iNetOrgPerson\nsn: User\ncn: Test2\nmail: success+testtwo@simulator.amazonses.com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
+    docker-compose exec openldap bash -c 'ldappasswd -s Password1 -D "cn=admin,dc=mm,dc=test,dc=com" -x "uid=test.two,ou=testusers,dc=mm,dc=test,dc=com" -w mostest'
+    docker-compose exec openldap bash -c 'echo -e "dn: cn=tgroup,ou=testusers,dc=mm,dc=test,dc=com\nobjectclass: groupOfUniqueNames\nuniqueMember: uid=test.one,ou=testusers,dc=mm,dc=test,dc=com" | ldapadd -x -D "cn=admin,dc=mm,dc=test,dc=com" -w mostest'
 
-  echo "Changing the config.json"
-  sed -i'.bak' 's|mmuser:mostest@tcp(dockerhost:3306)/mattermost_test?charset=utf8mb4,utf8|mmuser:mostest@tcp(mysql:3306)/mattermost_test?charset=utf8mb4,utf8|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
-  sed -i'.bak' 's|"SMTPServer": "dockerhost",|"SMTPServer": "inbucket",|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
-  sed -i'.bak' 's|"SMTPPort": "2500",|"SMTPPort": "10025",|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
-  sed -i'.bak' 's|"ConnectionUrl": "http://dockerhost:9200",|"ConnectionUrl": "http://elasticsearch:9200",|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
-
-  docker run -it -u root \
-   --privileged \
-   -v $GOPATH:/go \
-   -w /go/src/github.com/mattermost/mattermost-server/ \
-   --net $DCNAME-$BUILD_NUMBER\_mm-test \
-   -e GOPATH="/go" \
-   -e TEST_DATABASE_MYSQL_DSN="mmuser:mostest@tcp(mysql:3306)/mattermost_test?charset=utf8mb4,utf8\u0026readTimeout=30s\u0026writeTimeout=30s" \
-   -e TEST_DATABASE_POSTGRESQL_DSN="postgres://mmuser:mostest@postgres:5432/mattermost_test?sslmode=disable&connect_timeout=10" \
-   -e TEST_DATABASE_MYSQL_ROOT_PASSWD="mostest" \
-   -e CI_INBUCKET_HOST="inbucket" \
-   -e CI_MINIO_HOST="minio" \
-   -e CI_INBUCKET_PORT="10080" \
-   -e CI_MINIO_PORT="9000" \
-   -e CI_INBUCKET_SMTP_PORT="10025" \
-   -e CI_LDAP_HOST="openldap" \
-   -e IS_CI=true \
-   mattermost/mattermost-build-server:dec-7-2018 /bin/bash
+    docker run -it -u root \
+        --privileged \
+        -v $GOPATH:/go \
+        -w /go/src/github.com/mattermost/mattermost-server/ \
+        --net ${COMPOSE_PROJECT_NAME}_mm-test \
+        -e GOPATH="/go" \
+        -e TEST_DATABASE_MYSQL_DSN="mmuser:mostest@tcp(mysql:3306)/mattermost_test?charset=utf8mb4,utf8\u0026readTimeout=30s\u0026writeTimeout=30s" \
+        -e TEST_DATABASE_POSTGRESQL_DSN="postgres://mmuser:mostest@postgres:5432/mattermost_test?sslmode=disable&connect_timeout=10" \
+        -e TEST_DATABASE_MYSQL_ROOT_PASSWD="mostest" \
+        -e CI_INBUCKET_HOST="inbucket" \
+        -e CI_MINIO_HOST="minio" \
+        -e CI_INBUCKET_PORT="10080" \
+        -e CI_MINIO_PORT="9000" \
+        -e CI_INBUCKET_SMTP_PORT="10025" \
+        -e CI_LDAP_HOST="openldap" \
+        -e IS_CI=true \
+        -e MM_SQLSETTINGS_DATASOURCE="mmuser:mostest@tcp(mysql:3306)/mattermost_test?charset=utf8mb4,utf8" \
+        -e MM_EMAILSETTINGS_SMTPSERVER="inbucket" \
+        -e MM_EMAILSETTINGS_SMTPPORT="10025" \
+        -e MM_ELASTICSEARCHSETTINGS_CONNECTIONURL="http://elasticsearch:9200" \
+        mattermost/mattermost-build-server:dec-7-2018 /bin/bash
 }
 
 down()
 {
-  COMPOSE_PROJECT_NAME=$DCNAME-$BUILD_NUMBER docker-compose down
-
-  echo "Reverting the changes in the config.json"
-  sed -i'.bak' 's|mmuser:mostest@tcp(mysql:3306)/mattermost_test?charset=utf8mb4,utf8|mmuser:mostest@tcp(dockerhost:3306)/mattermost_test?charset=utf8mb4,utf8|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
-  sed -i'.bak' 's|"SMTPServer": "inbucket",|"SMTPServer": "dockerhost",|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
-  sed -i'.bak' 's|"SMTPPort": "10025",|"SMTPPort": "2500",|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
-  sed -i'.bak' 's|"ConnectionUrl": "http://elasticsearch:9200",|"ConnectionUrl": "http://dockerhost:9200",|g' $GOPATH/src/github.com/mattermost/mattermost-server/config/config.json
+    docker-compose down
 }
 
 # process arguments
@@ -70,16 +60,19 @@ do
         up
         break
         ;;
+
         down)
         echo "Stopping Containers"
         down
         break
         ;;
+
         --help)
         usage
         ;;
+
         *)
-        echoerr "Unknown argument: $1"
+        echo "Unknown argument: $1" >&2
         usage
         ;;
     esac
diff --git a/cmd/mattermost/commands/cmdtestlib.go b/cmd/mattermost/commands/cmdtestlib.go
index 24ae39a5c4..69d04adfbe 100644
--- a/cmd/mattermost/commands/cmdtestlib.go
+++ b/cmd/mattermost/commands/cmdtestlib.go
@@ -132,28 +132,39 @@ func (h *testHelper) execArgs(t *testing.T, args []string) []string {
 	return ret
 }
 
-// CheckCommand invokes the test binary, returning the output modified for assertion testing.
-func (h *testHelper) CheckCommand(t *testing.T, args ...string) string {
+func (h *testHelper) cmd(t *testing.T, args []string) *exec.Cmd {
 	path, err := os.Executable()
 	require.NoError(t, err)
-	output, err := exec.Command(path, h.execArgs(t, args)...).CombinedOutput()
+	cmd := exec.Command(path, h.execArgs(t, args)...)
+
+	cmd.Env = []string{}
+	for _, env := range os.Environ() {
+		// Ignore MM_SQLSETTINGS_DATASOURCE from the environment, since we override.
+		if strings.HasPrefix(env, "MM_SQLSETTINGS_DATASOURCE=") {
+			continue
+		}
+
+		cmd.Env = append(cmd.Env, env)
+	}
+
+	return cmd
+}
+
+// CheckCommand invokes the test binary, returning the output modified for assertion testing.
+func (h *testHelper) CheckCommand(t *testing.T, args ...string) string {
+	output, err := h.cmd(t, args).CombinedOutput()
 	require.NoError(t, err, string(output))
 	return strings.TrimSpace(strings.TrimSuffix(strings.TrimSpace(string(output)), "PASS"))
 }
 
 // RunCommand invokes the test binary, returning only any error.
 func (h *testHelper) RunCommand(t *testing.T, args ...string) error {
-	path, err := os.Executable()
-	require.NoError(t, err)
-	return exec.Command(path, h.execArgs(t, args)...).Run()
+	return h.cmd(t, args).Run()
 }
 
 // RunCommandWithOutput is a variant of RunCommand that returns the unmodified output and any error.
 func (h *testHelper) RunCommandWithOutput(t *testing.T, args ...string) (string, error) {
-	path, err := os.Executable()
-	require.NoError(t, err)
-
-	cmd := exec.Command(path, h.execArgs(t, args)...)
+	cmd := h.cmd(t, args)
 
 	var buf bytes.Buffer
 	reader, writer := io.Pipe()
@@ -166,7 +177,7 @@ func (h *testHelper) RunCommandWithOutput(t *testing.T, args ...string) (string,
 		close(done)
 	}()
 
-	err = cmd.Run()
+	err := cmd.Run()
 	writer.Close()
 	<-done