diff --git a/.travis.yml b/.travis.yml
index f3562fe..3d70588 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,8 +1,6 @@
 language: php
 
 php:
-  - '5.6'
-  - '7.0'
   - '7.1'
   - '7.2'
   - '7.3'
diff --git a/README.md b/README.md
index 03b4421..7b3dcbf 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,6 @@
 Install via composer.
 
 ```
-composer config minimum-stability dev
 composer require jukylin/jaeger-php
 ```
 
diff --git a/composer.json b/composer.json
index 0216a99..91eb902 100644
--- a/composer.json
+++ b/composer.json
@@ -5,9 +5,9 @@
   "license":           "Apache-2.0",
   "minimum-stability": "stable",
   "require":           {
-    "php": ">=5.6.0",
+    "php": "^7.1 || ^8.0",
     "packaged/thrift" : "0.10.0",
-    "opentracing/opentracing" : "1.0.0-beta5"
+    "opentracing/opentracing" : "^1.0"
   },
   "authors": [
     {
diff --git a/src/Jaeger/Config.php b/src/Jaeger/Config.php
index cba4c79..7b46389 100644
--- a/src/Jaeger/Config.php
+++ b/src/Jaeger/Config.php
@@ -77,7 +77,7 @@ public static function getInstance()
     public function initTracer($serverName, $agentHostPort = ''){
 
         if(self::$disabled){
-            return NoopTracer::create();
+            return new NoopTracer();
         }
 
         if($serverName == ''){
diff --git a/src/Jaeger/Jaeger.php b/src/Jaeger/Jaeger.php
index f317246..458c3bb 100644
--- a/src/Jaeger/Jaeger.php
+++ b/src/Jaeger/Jaeger.php
@@ -16,7 +16,7 @@
 namespace Jaeger;
 
 use Jaeger\Sampler\Sampler;
-use OpenTracing\Exceptions\UnsupportedFormat;
+use OpenTracing\UnsupportedFormatException;
 use OpenTracing\SpanContext;
 use OpenTracing\Formats;
 use OpenTracing\Tracer;
@@ -84,7 +84,7 @@ public function setTags(array $tags = []){
      * @param array $options
      * @return Span
      */
-    public function startSpan($operationName, $options = []){
+    public function startSpan(string $operationName, $options = []): \OpenTracing\Span{
 
         if (!($options instanceof StartSpanOptions)) {
             $options = StartSpanOptions::create($options);
@@ -135,11 +135,11 @@ public function setPropagator(Propagator $propagator){
      * @param string $format
      * @param $carrier
      */
-    public function inject(SpanContext $spanContext, $format, &$carrier){
+    public function inject(SpanContext $spanContext, string $format, &$carrier): void{
         if($format == Formats\TEXT_MAP){
             $this->propagator->inject($spanContext, $format, $carrier);
         }else{
-            throw UnsupportedFormat::forFormat($format);
+            throw UnsupportedFormatException::forFormat($format);
         }
     }
 
@@ -149,11 +149,11 @@ public function inject(SpanContext $spanContext, $format, &$carrier){
      * @param string $format
      * @param $carrier
      */
-    public function extract($format, $carrier){
+    public function extract(string $format, $carrier): ?\OpenTracing\SpanContext{
         if($format == Formats\TEXT_MAP){
             return $this->propagator->extract($format, $carrier);
         }else{
-            throw UnsupportedFormat::forFormat($format);
+            throw UnsupportedFormatException::forFormat($format);
         }
     }
 
@@ -171,12 +171,12 @@ public function reportSpan(){
     }
 
 
-    public function getScopeManager(){
+    public function getScopeManager(): \OpenTracing\ScopeManager{
         return $this->scopeManager;
     }
 
 
-    public function getActiveSpan(){
+    public function getActiveSpan(): ?\OpenTracing\Span {
         $activeScope = $this->getScopeManager()->getActive();
         if ($activeScope === null) {
             return null;
@@ -186,7 +186,7 @@ public function getActiveSpan(){
     }
 
 
-    public function startActiveSpan($operationName, $options = []){
+    public function startActiveSpan(string $operationName, $options = []): \OpenTracing\Scope{
         if (!$options instanceof StartSpanOptions) {
             $options = StartSpanOptions::create($options);
         }
@@ -209,7 +209,7 @@ private function getParentSpanContext(StartSpanOptions $options)
         $parentSpan = null;
 
         foreach ($references as $ref) {
-            $parentSpan = $ref->getContext();
+            $parentSpan = $ref->getSpanContext();
             if ($ref->isType(Reference::CHILD_OF)) {
                 return $parentSpan;
             }
@@ -250,7 +250,7 @@ public function gen128bit(){
     /**
      * 结束,发送信息到jaeger
      */
-    public function flush(){
+    public function flush(): void{
         $this->reportSpan();
         $this->reporter->close();
     }
diff --git a/src/Jaeger/Scope.php b/src/Jaeger/Scope.php
index e885d2d..654c812 100644
--- a/src/Jaeger/Scope.php
+++ b/src/Jaeger/Scope.php
@@ -35,7 +35,7 @@ public function __construct(ScopeManager $scopeManager, \OpenTracing\Span $span,
     }
 
 
-    public function close(){
+    public function close(): void{
         if ($this->finishSpanOnClose) {
             $this->span->finish();
         }
@@ -44,7 +44,7 @@ public function close(){
     }
 
 
-    public function getSpan(){
+    public function getSpan(): \OpenTracing\Span {
         return $this->span;
     }
 }
diff --git a/src/Jaeger/ScopeManager.php b/src/Jaeger/ScopeManager.php
index 3d11a06..edebaab 100644
--- a/src/Jaeger/ScopeManager.php
+++ b/src/Jaeger/ScopeManager.php
@@ -2,6 +2,7 @@
 
 namespace Jaeger;
 
+use OpenTracing;
 
 class ScopeManager implements \OpenTracing\ScopeManager{
 
@@ -14,7 +15,7 @@ class ScopeManager implements \OpenTracing\ScopeManager{
      * @param bool $finishSpanOnClose
      * @return Scope
      */
-    public function activate(\OpenTracing\Span $span, $finishSpanOnClose){
+    public function activate(\OpenTracing\Span $span, bool $finishSpanOnClose = self::DEFAULT_FINISH_SPAN_ON_CLOSE): OpenTracing\Scope{
         $scope = new Scope($this, $span, $finishSpanOnClose);
         $this->scopes[] = $scope;
         return $scope;
@@ -25,7 +26,7 @@ public function activate(\OpenTracing\Span $span, $finishSpanOnClose){
      * get last scope
      * @return mixed|null
      */
-    public function getActive(){
+    public function getActive(): ?OpenTracing\Scope{
         if (empty($this->scopes)) {
             return null;
         }
diff --git a/src/Jaeger/Span.php b/src/Jaeger/Span.php
index 8fee8fd..e2a0e6a 100644
--- a/src/Jaeger/Span.php
+++ b/src/Jaeger/Span.php
@@ -46,24 +46,23 @@ public function __construct($operationName, \OpenTracing\SpanContext $spanContex
     /**
      * @return string
      */
-    public function getOperationName(){
+    public function getOperationName(): string{
         return $this->operationName;
     }
 
     /**
      * @return SpanContext
      */
-    public function getContext(){
+    public function getContext(): \OpenTracing\SpanContext{
         return $this->spanContext;
     }
 
     /**
      * @param float|int|\DateTimeInterface|null $finishTime if passing float or int
      * it should represent the timestamp (including as many decimal places as you need)
-     * @param array $logRecords
      * @return mixed
      */
-    public function finish($finishTime = null, array $logRecords = []){
+    public function finish($finishTime = null): void{
         $this->finishTime = $finishTime == null ? $this->microtimeToInt() : $finishTime;
         $this->duration = $this->finishTime - $this->startTime;
     }
@@ -71,12 +70,12 @@ public function finish($finishTime = null, array $logRecords = []){
     /**
      * @param string $newOperationName
      */
-    public function overwriteOperationName($newOperationName){
+    public function overwriteOperationName(string $newOperationName): void{
         $this->operationName = $newOperationName;
     }
 
 
-    public function setTag($key, $value){
+    public function setTag(string $key, $value): void{
         $this->tags[$key] = $value;
     }
 
@@ -88,7 +87,7 @@ public function setTag($key, $value){
      * @param int|float|\DateTimeInterface $timestamp
      * @throws SpanAlreadyFinished if the span is already finished
      */
-    public function log(array $fields = [], $timestamp = null){
+    public function log(array $fields = [], $timestamp = null): void{
         $log['timestamp'] = $timestamp ? $timestamp : $this->microtimeToInt();
         $log['fields'] = $fields;
         $this->logs[] = $log;
@@ -102,20 +101,20 @@ public function log(array $fields = [], $timestamp = null){
      * @param string $value
      * @throws SpanAlreadyFinished if the span is already finished
      */
-    public function addBaggageItem($key, $value){
+    public function addBaggageItem(string $key, string $value): void{
         $this->log([
             'event' => 'baggage',
             'key' => $key,
             'value' => $value,
         ]);
-        return $this->spanContext->withBaggageItem($key, $value);
+        $this->spanContext->withBaggageItem($key, $value);
     }
 
     /**
      * @param string $key
      * @return string|null
      */
-    public function getBaggageItem($key){
+    public function getBaggageItem(string $key): ?string{
         return $this->spanContext->getBaggageItem($key);
     }
 
diff --git a/src/Jaeger/SpanContext.php b/src/Jaeger/SpanContext.php
index 955d023..79a7ff3 100644
--- a/src/Jaeger/SpanContext.php
+++ b/src/Jaeger/SpanContext.php
@@ -53,14 +53,14 @@ public function __construct($spanId, $parentId, $flags, $baggage = null, $debugI
     }
 
 
-    public function getBaggageItem($key){
+    public function getBaggageItem(string $key): ?string{
         return isset($this->baggage[$key]) ? $this->baggage[$key] : null;
     }
 
 
-    public function withBaggageItem($key, $value){
+    public function withBaggageItem(string $key, string $value): \OpenTracing\SpanContext{
         $this->baggage[$key] = $value;
-        return true;
+        return $this;
     }
 
     public function getIterator()
diff --git a/src/Jaeger/Thrift/JaegerThriftSpan.php b/src/Jaeger/Thrift/JaegerThriftSpan.php
index 446fdd4..8cda65a 100644
--- a/src/Jaeger/Thrift/JaegerThriftSpan.php
+++ b/src/Jaeger/Thrift/JaegerThriftSpan.php
@@ -99,7 +99,7 @@ private function buildReferences($references){
             }else if($ref->isType(Reference::FOLLOWS_FROM)){
                 $type = SpanRefType::FOLLOWS_FROM;
             }
-            $ctx = $ref->getContext();
+            $ctx = $ref->getSpanContext();
             $spanRef[] = [
                 'refType' => $type,
                 'traceIdLow' => $ctx->traceIdLow,
diff --git a/tests/JaegerTest.php b/tests/JaegerTest.php
index 7f2eaa0..bca0615 100644
--- a/tests/JaegerTest.php
+++ b/tests/JaegerTest.php
@@ -82,7 +82,7 @@ public function testInjectUnSupportFormat(){
         $Jaeger->setPropagator(new JaegerPropagator());
 
         $context = new SpanContext(1, 1, 1, null, 1);
-        $this->expectExceptionMessage('The format \'http_headers\' is not supported.');
+        $this->expectExceptionMessage('The format "http_headers" is not supported.');
 
         $Jaeger->inject($context, Formats\HTTP_HEADERS, $_SERVER);
     }
@@ -106,7 +106,7 @@ public function testExtractUnSupportFormat(){
         $Jaeger->setPropagator(new JaegerPropagator());
 
         $_SERVER[strtoupper(Constants\Tracer_State_Header_Name)] = '1:1:1:1';
-        $this->expectExceptionMessage('The format \'http_headers\' is not supported.');
+        $this->expectExceptionMessage('The format "http_headers" is not supported.');
 
         $Jaeger->extract(Formats\HTTP_HEADERS, $_SERVER);
     }
@@ -125,17 +125,17 @@ public function testStartSpanWithFollowsFromTypeRef()
         $jaeger = $this->getJaeger();
         $rootSpan = $jaeger->startSpan('root-a');
         $childSpan = $jaeger->startSpan('span-a', [
-            'references' => Reference::create(Reference::FOLLOWS_FROM, $rootSpan),
+            'references' => Reference::createForSpan(Reference::FOLLOWS_FROM, $rootSpan),
         ]);
 
         $this->assertSame($childSpan->spanContext->traceIdLow, $rootSpan->spanContext->traceIdLow);
-        $this->assertSame(current($childSpan->references)->getContext(), $rootSpan->spanContext);
+        $this->assertSame(current($childSpan->references)->getSpanContext(), $rootSpan->spanContext);
 
         $otherRootSpan = $jaeger->startSpan('root-a');
         $childSpan = $jaeger->startSpan('span-b', [
             'references' => [
-                Reference::create(Reference::FOLLOWS_FROM, $rootSpan),
-                Reference::create(Reference::FOLLOWS_FROM, $otherRootSpan),
+                Reference::createForSpan(Reference::FOLLOWS_FROM, $rootSpan),
+                Reference::createForSpan(Reference::FOLLOWS_FROM, $otherRootSpan),
             ],
         ]);
 
@@ -150,8 +150,8 @@ public function testStartSpanWithChildOfTypeRef()
         $otherRootSpan = $jaeger->startSpan('root-b');
         $childSpan = $jaeger->startSpan('span-a', [
             'references' => [
-                Reference::create(Reference::CHILD_OF, $rootSpan),
-                Reference::create(Reference::CHILD_OF, $otherRootSpan),
+                Reference::createForSpan(Reference::CHILD_OF, $rootSpan),
+                Reference::createForSpan(Reference::CHILD_OF, $otherRootSpan),
             ],
         ]);
 
@@ -175,8 +175,8 @@ public function testStartSpanWithAllRefType()
         $otherRootSpan = $jaeger->startSpan('root-b');
         $childSpan = $jaeger->startSpan('span-a', [
             'references' => [
-                Reference::create(Reference::FOLLOWS_FROM, $rootSpan),
-                Reference::create(Reference::CHILD_OF, $otherRootSpan),
+                Reference::createForSpan(Reference::FOLLOWS_FROM, $rootSpan),
+                Reference::createForSpan(Reference::CHILD_OF, $otherRootSpan),
             ],
         ]);
 
diff --git a/tests/SpanContextTest.php b/tests/SpanContextTest.php
index 8f7dae2..0d9a341 100644
--- a/tests/SpanContextTest.php
+++ b/tests/SpanContextTest.php
@@ -36,7 +36,7 @@ public function testNew(){
     public function testWithBaggageItem(){
         $spanContext = $this->getSpanContext();
         $res = $spanContext->withBaggageItem('version', '2.0.0');
-        $this->assertTrue($res);
+        $this->assertInstanceOf(SpanContext::class, $res);
     }
 
 
@@ -45,7 +45,7 @@ public function testGetBaggageItem(){
         $res = $spanContext->withBaggageItem('version', '2.0.0');
 
         $version = $spanContext->getBaggageItem('version');
-        $this->assertTrue($res == $version);
+        $this->assertTrue($version == '2.0.0');
 
         $service = $spanContext->getBaggageItem('service');
         $this->assertNull($service);