diff --git a/WEB-INF/resources/en.lang.php b/WEB-INF/resources/en.lang.php
index 5b433b0a..9bb42523 100644
--- a/WEB-INF/resources/en.lang.php
+++ b/WEB-INF/resources/en.lang.php
@@ -83,6 +83,9 @@
 'error.format' => 'Invalid file format.',
 'error.user_count' => 'Limit on user count.',
 'error.expired' => 'Expiration date reached.',
+'error.jwt_token_not_found' => 'JWT not found in request.',
+'error.jwt_invalid_token' => 'JWT is not valid.',
+'error.api_no_handler' => 'Invalid request, endpoint %s is not valid',
 // Meaning of error.file_storage: an (unspecified) error occurred when trying to communicate with remote
 // file storage server (the one that handles attachments). It is a generic message telling us that
 // "something went wrong" when trying to do some operation with attachments.
diff --git a/api.php b/api.php
new file mode 100644
index 00000000..54d2c0f1
--- /dev/null
+++ b/api.php
@@ -0,0 +1,105 @@
+<?php
+use Firebase\JWT\JWT;
+use Firebase\JWT\Key;
+
+header("Access-Control-Allow-Headers: Content-Type, Origin, Authorization, X-Auth-Token");
+header('Access-Control-Allow-Credentials: true');
+header("Access-Control-Allow-Origin: *");
+
+if($_SERVER['REQUEST_METHOD']=="OPTIONS"){
+    exit(0);
+}
+
+require_once('initialize.php');
+require_once('api_lib.php');
+require_once 'api_route_projects.php';
+require_once 'api_route_time.php';
+require_once 'api_route_clients.php';
+require_once(__DIR__.'/vendor/autoload.php');
+
+$apiReq = preg_replace('/^.*\/api.php\//i','',$_SERVER['REQUEST_URI']);
+$params = explode('/',$apiReq);
+$domain = array_shift($params);
+$requestBody = file_get_contents("php://input");
+if(!empty($requestBody) ){
+    $body = json_decode($requestBody,true);
+}
+
+if($domain == "authenticate"){
+    $loginSucceeded = $auth->doLogin($body['username'], $body['password']);
+    if ($loginSucceeded) {
+        $user = new ttUser(null, $auth->getUserId());
+        echo json_encode(array('token'=>generate_decoded_token($user)));
+    } else {
+        send_error('error.auth');
+    }
+    exit;
+}else {
+    $decodedTokenExistsInHeader = preg_match('/Bearer\s(\S+)/', $_SERVER['HTTP_AUTHORIZATION'], $matcheddecodedTokenArr);
+    if (! $decodedTokenExistsInHeader) {
+        send_error('error.jwt_token_not_found');
+        exit;
+    }else {
+        $decodedToken = decode_token($matcheddecodedTokenArr[1]);
+        if(! validate_decodedToken($decodedToken)){
+            exit;
+        }
+        $user = new ttUser(null, $decodedToken->sub->id);
+        route_request($domain,$params,$body,$user);
+    }
+}
+
+function generate_decoded_token($user) {
+    $current_ts = (new DateTimeImmutable())->getTimestamp();
+    $payload = [
+        'iss' => $_SERVER['SERVER_NAME'],
+        'aud' => $_SERVER['SERVER_NAME'],
+        'iat' => $current_ts,
+        'nbf' => $current_ts,
+        'sub' => get_subject($user),
+        'exp' => $current_ts+(3600*24)
+    ];
+    return JWT::encode($payload, JWT_KEY, JWT_ALGO);
+}
+
+function get_subject($user) {
+    return array(
+        'login' => $user->login,
+        'name' => $user->name,
+        'id' => $user->id,
+        'org_id' => $user->org_id,
+        'group_id' => $user->group_id,
+        'group_name' => $user->group_name,
+        'role_id' => $user->role_id,
+        'role_name' => $user->role_name,
+        'rank' => $user->rank,
+        'email' => $user->email,
+    );
+}
+
+function decode_token($jwt) {
+    return JWT::decode($jwt, new key (JWT_KEY, JWT_ALGO));
+}
+
+function validate_decodedToken($decodedToken) {    
+    $now = new DateTimeImmutable();
+    $serverName = $_SERVER['SERVER_NAME'];
+    if ($decodedToken->iss !== $serverName ||
+        $decodedToken->nbf > $now->getTimestamp() ||
+        $decodedToken->exp < $now->getTimestamp()) {
+        send_error('error.jwt_invalid_token');
+        return false;
+    }
+    
+    return true;
+}
+
+function route_request($domain, $params, $body, $user) {
+    $routeHandler = "handle_req_".$domain;
+    if(function_exists($routeHandler)) {
+        $routeHandler($params,$body,$user);
+    }else{
+        send_error('error.api_no_handler', $domain);
+    }
+    
+}
\ No newline at end of file
diff --git a/api_installation.txt b/api_installation.txt
new file mode 100644
index 00000000..7401154c
--- /dev/null
+++ b/api_installation.txt
@@ -0,0 +1,10 @@
+Copy all files with api_*.php 
+Add config to WEBINF/config.php
+Copy WEBINF/resource/en.lang.php
+
+// API Module
+define('JWT_KEY', 'LjtkLTGGSUudOxI03tcoZdf3yy8vgdMS7PlZaXDB');
+define('JWT_ALGO', 'HS256');
+
+
+Copy composer-lock and composer.json files
\ No newline at end of file
diff --git a/api_lib.php b/api_lib.php
new file mode 100644
index 00000000..70e14e6d
--- /dev/null
+++ b/api_lib.php
@@ -0,0 +1,7 @@
+<?php
+
+function send_error($error, $params=null,$code=400) {
+    global $i18n;
+    http_response_code($code);
+    echo json_encode(array('error'=>$i18n->get($error, $args)));
+}
\ No newline at end of file
diff --git a/api_route_clients.php b/api_route_clients.php
new file mode 100644
index 00000000..c575aade
--- /dev/null
+++ b/api_route_clients.php
@@ -0,0 +1,14 @@
+<?php
+
+import('ttGroupHelper');
+function handle_req_clients($params,$body,$user) {
+    $action = "list";
+    if(count($params)>0) {
+        $action = $params[0];
+    }
+    switch($action) {
+        case 'list':
+            echo json_encode(ttGroupHelper::getActiveClients(true));
+            break;
+    }
+}
diff --git a/api_route_projects.php b/api_route_projects.php
new file mode 100644
index 00000000..0a4ac24b
--- /dev/null
+++ b/api_route_projects.php
@@ -0,0 +1,31 @@
+<?php
+import('ttConfigHelper');
+
+function handle_req_projects($params,$body,$user) {
+    
+    $action = "list";
+    if(count($params)>0) {
+        $action = $params[0];
+    }
+    
+    switch($action) {
+        case 'list':
+            echo json_encode(list_projects($user));
+            break;
+    }
+}
+
+function list_projects($user) {
+    $config = new ttConfigHelper($user->getConfig());
+
+    if ($user->can('track_time')) {
+        $rank = $user->getMaxRankForGroup($group_id);
+        if ($user->can('track_own_time'))
+          $options = array('status'=>ACTIVE,'max_rank'=>$rank,'include_self'=>true,'self_first'=>true);
+        else
+          $options = array('status'=>ACTIVE,'max_rank'=>$rank);
+        $user_list = $user->getUsers($options);
+      }
+      $options['include_templates'] = $user->isPluginEnabled('tp') && $config->getDefinedValue('bind_templates_with_projects');
+      return $user->getAssignedProjects($options);
+}
\ No newline at end of file
diff --git a/api_route_time.php b/api_route_time.php
new file mode 100644
index 00000000..b5af0f8e
--- /dev/null
+++ b/api_route_time.php
@@ -0,0 +1,135 @@
+<?php
+import('ttTimeHelper');
+
+function handle_req_time($params,$body,$user) {
+    $action = "add";
+    // cl_client, $cl_task, $cl_project,  $cl_start, $cl_finish, $cl_duration, $cl_billable=1
+    if(count($params)>0) {
+        $action = $params[0];
+    }
+    
+    switch($action) {
+        case 'add':
+            echo json_encode(add_time_entry($body));
+            break;
+    }
+}
+
+function add_time_entry($time_entry) {
+    global $user, $err, $i18n;
+    $cl_client = null; $cl_task = null; $cl_project = null;  $cl_start = null; $cl_finish = null; $cl_duration = null; $cl_billable=1;
+    
+    $config = new ttConfigHelper($user->getConfig());
+    $showClient = $user->isPluginEnabled('cl');
+    $trackingMode = $user->getTrackingMode();
+    $showProject = MODE_PROJECTS == $trackingMode || MODE_PROJECTS_AND_TASKS == $trackingMode;
+    $showTask = MODE_PROJECTS_AND_TASKS == $trackingMode;
+    $taskRequired = false;
+    $recordType = $user->getRecordType();
+    $showStart = TYPE_START_FINISH == $recordType || TYPE_ALL == $recordType;
+    $showDuration = TYPE_DURATION == $recordType || TYPE_ALL == $recordType;
+    $oneUncompleted = $config->getDefinedValue('one_uncompleted');
+
+    extract($time_entry, EXTR_OVERWRITE);
+    $selected_date = new ttDate($cl_date);
+
+    if ($showTask) $taskRequired = $config->getDefinedValue('task_required');
+
+    // Validate user input.
+    if ($showClient && $user->isOptionEnabled('client_required') && !$cl_client){
+      $i18n->add('error.client');
+      return;
+    }
+    // Validate input in time custom fields.
+    if (isset($custom_fields) && $custom_fields->timeFields) {
+      foreach ($timeCustomFields as $timeField) {
+        // Validation is the same for text and dropdown fields.
+        if (!ttValidString($timeField['value'], !$timeField['required'])) $err->add($i18n->get('error.field'), htmlspecialchars($timeField['label']));
+      }
+    }
+    if ($showProject) {
+      if (!$cl_project) $err->add($i18n->get('error.project'));
+    }
+    if ($showTask && $taskRequired) {
+      if (!$cl_task) $err->add($i18n->get('error.task'));
+    }
+    if (strlen($cl_duration) == 0) {
+      if ($cl_start || $cl_finish) {
+        if (!ttTimeHelper::isValidTime($cl_start))
+          $err->add($i18n->get('error.field'), $i18n->get('label.start'));
+        if ($cl_finish) {
+          if (!ttTimeHelper::isValidTime($cl_finish))
+            $err->add($i18n->get('error.field'), $i18n->get('label.finish'));
+          if (!ttTimeHelper::isValidInterval($cl_start, $cl_finish))
+            $err->add($i18n->get('error.interval'), $i18n->get('label.finish'), $i18n->get('label.start'));
+        }
+      } else {
+        if ($showStart) {
+          $err->add($i18n->get('error.empty'), $i18n->get('label.start'));
+          $err->add($i18n->get('error.empty'), $i18n->get('label.finish'));
+        }
+        if ($showDuration)
+          $err->add($i18n->get('error.empty'), $i18n->get('label.duration'));
+      }
+    } else {
+      if (false === ttTimeHelper::postedDurationToMinutes($cl_duration))
+        $err->add($i18n->get('error.field'), $i18n->get('label.duration'));
+    }
+    if (!ttValidString($cl_note, true)) $err->add($i18n->get('error.field'), $i18n->get('label.note'));
+    if ($user->isPluginEnabled('tp') && !ttValidTemplateText($cl_note)) {
+      $err->add($i18n->get('error.field'), $i18n->get('label.note'));
+    }
+    // Finished validating user input.
+
+    // Prohibit creating entries in future.
+    if (!$user->isOptionEnabled('future_entries')) {
+      $server_tomorrow = new ttDate();
+      $server_tomorrow->incrementDay();
+      if ($selected_date->after($server_tomorrow))
+        $err->add($i18n->get('error.future_date'));
+    }
+
+    // Prohibit creating entries in locked range.
+    if ($user->isDateLocked($selected_date))
+      $err->add($i18n->get('error.range_locked'));
+
+    // Prohibit creating another uncompleted record.
+    if ($err->no() && $oneUncompleted) {
+      if (($not_completed_rec = ttTimeHelper::getUncompleted($user_id)) && (($cl_finish == '') && ($cl_duration == '')))
+        $err->add($i18n->get('error.uncompleted_exists')." <a href = 'time_edit.php?id=".$not_completed_rec['id']."'>".$i18n->get('error.goto_uncompleted')."</a>");
+    }
+
+    // Prohibit creating an overlapping record.
+    if ($err->no()) {
+      if (ttTimeHelper::overlaps($user_id, $cl_date, $cl_start, $cl_finish))
+        $err->add($i18n->get('error.overlap'));
+    }
+    
+    // Insert record.
+    if ($err->no()) {
+      $id = ttTimeHelper::insert(array(
+        'date' => $cl_date,
+        'client' => $cl_client,
+        'project' => $cl_project,
+        'task' => $cl_task,
+        'start' => $cl_start,
+        'finish' => $cl_finish,
+        'duration' => $cl_duration,
+        'note' => $cl_note,
+        'billable' => $cl_billable));
+
+      // Insert time custom fields if we have them.
+      $result = true;
+      if ($id && isset($custom_fields) && $custom_fields->timeFields) {
+        $result = $custom_fields->insertTimeFields($id, $timeCustomFields);
+      }
+
+      if ($id && $result && $err->no()) {
+        return array('id'=> $id,'result' => $result);
+      }
+      $err->add($i18n->get('error.db'));
+      
+    }
+
+    return array('error'=>$err->getErrors());
+}
\ No newline at end of file
diff --git a/composer.json b/composer.json
new file mode 100644
index 00000000..36557161
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,5 @@
+{
+    "require": {
+        "firebase/php-jwt": "^6.0"
+    }
+}
diff --git a/composer.lock b/composer.lock
new file mode 100644
index 00000000..e0aeaf37
--- /dev/null
+++ b/composer.lock
@@ -0,0 +1,76 @@
+{
+    "_readme": [
+        "This file locks the dependencies of your project to a known state",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
+        "This file is @generated automatically"
+    ],
+    "content-hash": "0f2c3a727a6da4acd150a914dd810575",
+    "packages": [
+        {
+            "name": "firebase/php-jwt",
+            "version": "v6.0.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/firebase/php-jwt.git",
+                "reference": "0541cba75ab108ef901985e68055a92646c73534"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/firebase/php-jwt/zipball/0541cba75ab108ef901985e68055a92646c73534",
+                "reference": "0541cba75ab108ef901985e68055a92646c73534",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": ">=4.8 <=9"
+            },
+            "suggest": {
+                "paragonie/sodium_compat": "Support EdDSA (Ed25519) signatures when libsodium is not present"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Firebase\\JWT\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "BSD-3-Clause"
+            ],
+            "authors": [
+                {
+                    "name": "Neuman Vong",
+                    "email": "neuman+pear@twilio.com",
+                    "role": "Developer"
+                },
+                {
+                    "name": "Anant Narayanan",
+                    "email": "anant@php.net",
+                    "role": "Developer"
+                }
+            ],
+            "description": "A simple library to encode and decode JSON Web Tokens (JWT) in PHP. Should conform to the current spec.",
+            "homepage": "https://github.com/firebase/php-jwt",
+            "keywords": [
+                "jwt",
+                "php"
+            ],
+            "support": {
+                "issues": "https://github.com/firebase/php-jwt/issues",
+                "source": "https://github.com/firebase/php-jwt/tree/v6.0.0"
+            },
+            "time": "2022-01-24T15:18:34+00:00"
+        }
+    ],
+    "packages-dev": [],
+    "aliases": [],
+    "minimum-stability": "stable",
+    "stability-flags": [],
+    "prefer-stable": false,
+    "prefer-lowest": false,
+    "platform": [],
+    "platform-dev": [],
+    "plugin-api-version": "2.2.0"
+}