diff --git a/scripts/authelia-scripts-start b/scripts/authelia-scripts-start
index f28cc635d..b6a5d05b3 100755
--- a/scripts/authelia-scripts-start
+++ b/scripts/authelia-scripts-start
@@ -44,9 +44,12 @@ function startServer() {
     console.log('Authelia is interrupted. Consider removing ' + AUTHELIA_INTERRUPT_FILENAME + ' if it\'s not expected.');
     return;
   }
-  serverProcess = spawn('./scripts/run-dev-server.sh', [`test/suites/${program.suite}/config.yml`]);
-  serverProcess.stdout.pipe(process.stdout);
-  serverProcess.stderr.pipe(process.stderr);
+  exec('./node_modules/.bin/tslint', ['-c', 'server/tslint.json', '-p', 'server/tsconfig.json'])
+    .then(function() {
+      serverProcess = spawn('./scripts/run-dev-server.sh', [`test/suites/${program.suite}/config.yml`]);
+      serverProcess.stdout.pipe(process.stdout);
+      serverProcess.stderr.pipe(process.stderr);
+    });
 }
 
 let clientProcess;
@@ -97,7 +100,8 @@ function killClient(onExit) {
 }
 
 function generateConfigurationSchema() {
-  exec('./node_modules/.bin/typescript-json-schema -o server/src/lib/configuration/Configuration.schema.json --strictNullChecks --required server/tsconfig.json Configuration');
+  return ixec('./node_modules/.bin/typescript-json-schema',
+    ['-o', 'server/src/lib/configuration/Configuration.schema.json', '--strictNullChecks', '--required', 'server/tsconfig.json', 'Configuration']);
 }
 
 function reload(path) {
diff --git a/server/src/lib/authentication/AuthenticationError.ts b/server/src/lib/authentication/AuthenticationError.ts
index 8203b345a..9285ac49c 100644
--- a/server/src/lib/authentication/AuthenticationError.ts
+++ b/server/src/lib/authentication/AuthenticationError.ts
@@ -8,4 +8,4 @@ class AuthenticationError extends Error {
   }
 }
 
-export default AuthenticationError
\ No newline at end of file
+export default AuthenticationError;
\ No newline at end of file
diff --git a/server/src/lib/routes/firstfactor/post.ts b/server/src/lib/routes/firstfactor/post.ts
index 2a2671d4a..f6ec8a661 100644
--- a/server/src/lib/routes/firstfactor/post.ts
+++ b/server/src/lib/routes/firstfactor/post.ts
@@ -63,8 +63,8 @@ export default function (vars: ServerVariables) {
         vars.regulator.mark(username, true);
       })
       .then(function() {
-        const targetUrl = ObjectPath.get(req, 'headers.x-target-url', null);
-        
+        const targetUrl = ObjectPath.get(req, "headers.x-target-url", undefined);
+
         if (!targetUrl) {
           res.status(204);
           res.send();
@@ -76,12 +76,12 @@ export default function (vars: ServerVariables) {
           const resObject: Object = {
             domain: resource.domain,
             resource: resource.path,
-          }
+          };
 
           const subject: Subject = {
             user: authSession.userid,
             groups: authSession.groups
-          }
+          };
 
           const authorizationLevel = vars.authorizer.authorization(resObject, subject);
           if (authorizationLevel <= AuthorizationLevel.ONE_FACTOR) {