diff --git a/.github/workflows/static-analysis.yml b/.github/workflows/static-analysis.yml
index fcfaba9c..7d27dc07 100644
--- a/.github/workflows/static-analysis.yml
+++ b/.github/workflows/static-analysis.yml
@@ -4,20 +4,24 @@ on:  # yamllint disable-line rule:truthy
   pull_request:
     paths:
       - 'src/**'
-      - 'tests/**'
       - 'bin/trap'
       - '.php-cs-fixer.dist.php'
+      - 'psalm*'
+      - 'phpstan*'
+      - 'composer.*'
   push:
     paths:
       - 'src/**'
-      - 'tests/**'
       - 'bin/trap'
       - '.php-cs-fixer.dist.php'
+      - 'psalm*'
+      - 'phpstan*'
+      - 'composer.*'
 
 name: 🔍 Static analysis
 
 jobs:
-  static-analysis:
+  psalm:
     timeout-minutes: 4
     runs-on: ${{ matrix.os }}
     concurrency:
@@ -68,5 +72,53 @@ jobs:
       - name: 🔍 Run static analysis using vimeo/psalm
         run: composer psalm:ci
 
+  phpstan:
+    timeout-minutes: 4
+    runs-on: ${{ matrix.os }}
+    concurrency:
+      cancel-in-progress: true
+      group: static-analysis-${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+    strategy:
+      fail-fast: true
+      matrix:
+        os:
+          - ubuntu-latest
+        php-version:
+          - '8.2'
+        dependencies:
+          - locked
+    steps:
+      - name: 📦 Check out the codebase
+        uses: actions/checkout@v4.1.5
+
+      - name: 🛠️ Setup PHP
+        uses: shivammathur/setup-php@2.30.4
+        with:
+          php-version: ${{ matrix.php-version }}
+          extensions: none, ctype, curl, dom, json, mbstring, phar, simplexml, tokenizer, xml, xmlwriter, sockets, opcache, pcntl, posix
+          ini-values: error_reporting=E_ALL
+          coverage: none
+
+      - name: 🛠️ Setup problem matchers
+        run: echo "::add-matcher::${{ runner.tool_cache }}/php.json"
+
+      - name: 🤖 Validate composer.json and composer.lock
+        run: composer validate --ansi --strict
+
+      - name: 🔍 Get composer cache directory
+        uses: wayofdev/gh-actions/actions/composer/get-cache-directory@v3.1.0
+
+      - name: ♻️ Restore cached dependencies installed with composer
+        uses: actions/cache@v4.0.2
+        with:
+          path: ${{ env.COMPOSER_CACHE_DIR }}
+          key: php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('composer.lock') }}
+          restore-keys: php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-
+
+      - name: 📥 Install "${{ matrix.dependencies }}" dependencies
+        uses: wayofdev/gh-actions/actions/composer/install@v3.1.0
+        with:
+          dependencies: ${{ matrix.dependencies }}
+
       - name: 🔍 Run static analysis using phpstan/phpstan
         run: composer stan:ci
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index c5c30362..d03a4e43 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -6,6 +6,8 @@ parameters:
     paths:
         - bin/
         - src/
-        - tests/
         - .php-cs-fixer.dist.php
+    excludePaths:
+        analyse:
+            - src/Test/Proto/
     tmpDir: .build/phpstan/
diff --git a/tests/Unit/Client/FunctionTrapTest.php b/tests/Unit/Client/FunctionTrapTest.php
index e3cd7399..51c51196 100644
--- a/tests/Unit/Client/FunctionTrapTest.php
+++ b/tests/Unit/Client/FunctionTrapTest.php
@@ -20,6 +20,6 @@ public function testLeak(): void
         trap($object, $object);
         unset($object);
 
-        $this->assertNull($ref->get());
+        self::assertNull($ref->get());
     }
 }
diff --git a/tests/Unit/Client/TrTest.php b/tests/Unit/Client/TrTest.php
index 5bb22e03..0ce8b85b 100644
--- a/tests/Unit/Client/TrTest.php
+++ b/tests/Unit/Client/TrTest.php
@@ -51,27 +51,27 @@ public function testLeak(): void
         tr($object, $object);
         unset($object);
 
-        $this->assertNull($ref->get());
+        self::assertNull($ref->get());
     }
 
     public function testReturn(): void
     {
-        $this->assertSame(42, tr(42));
-        $this->assertSame(42, tr(named: 42));
-        $this->assertSame(42, tr(42, 43));
-        $this->assertSame('foo', tr(...['0' => 'foo', 42 => 90]));
-        $this->assertNull(tr(null));
+        self::assertSame(42, tr(42));
+        self::assertSame(42, tr(named: 42));
+        self::assertSame(42, tr(42, 43));
+        self::assertSame('foo', tr(...['0' => 'foo', 42 => 90]));
+        self::assertNull(tr(null));
     }
 
     public function testReturnSendsDumpOnce(): void
     {
         $dumper = $this->getMockBuilder(DataDumperInterface::class)
             ->getMock();
-        $dumper->expects($this->once())
+        $dumper->expects(self::once())
             ->method('dump')
             ->willReturnArgument(1);
         Dumper::setDumper($dumper);
 
-        $this->assertSame(42, tr(42));
+        self::assertSame(42, tr(42));
     }
 }
diff --git a/tests/Unit/Client/TrapTest.php b/tests/Unit/Client/TrapTest.php
index 52ac0740..da5d914b 100644
--- a/tests/Unit/Client/TrapTest.php
+++ b/tests/Unit/Client/TrapTest.php
@@ -20,7 +20,7 @@ public static function provideTrapTimes(): iterable
     public function testLabel(): void
     {
         trap(FooName: 'foo-value');
-        $this->assertSame('FooName', self::$lastData->getContext()['label']);
+        self::assertSame('FooName', self::$lastData->getContext()['label']);
     }
 
     public function testSimpleContext(): void
@@ -61,11 +61,11 @@ public function testStackTrace(): void
     {
         $line = __FILE__ . ':' . __LINE__ and trap()->stackTrace();
 
-        $this->assertArrayHasKey('trace', self::$lastData->getValue());
+        self::assertArrayHasKey('trace', self::$lastData->getValue());
 
         $neededLine = \array_key_first(self::$lastData->getValue()['trace']->getValue());
 
-        $this->assertStringContainsString($line, $neededLine);
+        self::assertStringContainsString($line, $neededLine);
     }
 
     /**
@@ -89,7 +89,7 @@ public function testLeak(): void
         trap($object, $object);
         unset($object);
 
-        $this->assertNull($ref->get());
+        self::assertNull($ref->get());
     }
 
     public function testTrapOnce(): void
@@ -103,29 +103,29 @@ public function testTrapOnce(): void
 
     public function testReturn(): void
     {
-        $this->assertSame(42, trap(42)->return());
-        $this->assertSame(42, trap(named: 42)->return());
-        $this->assertSame(42, trap(named: 42)->return('bad-name'));
-        $this->assertSame(42, trap(42, 43)->return());
-        $this->assertSame(42, trap(int: 42, foo: 'bar')->return('int'));
-        $this->assertSame(42, trap(int: 42, foo: 'bar')->return(0));
-        $this->assertSame('foo', trap(...['0' => 'foo', 42 => 90])->return());
-        $this->assertNull(trap(null)->return());
-
-        $this->expectException(\InvalidArgumentException::class);
-        $this->assertSame(42, trap(42, 43)->return(10));
+        self::assertSame(42, trap(42)->return());
+        self::assertSame(42, trap(named: 42)->return());
+        self::assertSame(42, trap(named: 42)->return('bad-name'));
+        self::assertSame(42, trap(42, 43)->return());
+        self::assertSame(42, trap(int: 42, foo: 'bar')->return('int'));
+        self::assertSame(42, trap(int: 42, foo: 'bar')->return(0));
+        self::assertSame('foo', trap(...['0' => 'foo', 42 => 90])->return());
+        self::assertNull(trap(null)->return());
+
+        self::expectException(\InvalidArgumentException::class);
+        self::assertSame(42, trap(42, 43)->return(10));
     }
 
     public function testReturnSendsDumpOnce(): void
     {
         $dumper = $this->getMockBuilder(DataDumperInterface::class)
             ->getMock();
-        $dumper->expects($this->once())
+        $dumper->expects(self::once())
             ->method('dump')
             ->willReturnArgument(1);
         Dumper::setDumper($dumper);
 
-        $this->assertSame(42, trap(42)->return());
+        self::assertSame(42, trap(42)->return());
     }
 
     /**
diff --git a/tests/Unit/Handler/Router/RouterTest.php b/tests/Unit/Handler/Router/RouterTest.php
index 67090e65..8050ffe2 100644
--- a/tests/Unit/Handler/Router/RouterTest.php
+++ b/tests/Unit/Handler/Router/RouterTest.php
@@ -62,7 +62,7 @@ public function testRouteAssertions(string $class): void
             );
 
             Router::assert($routes, $asserts);
-            $this->assertTrue(true, (string) $method . ' passed');
+            self::assertTrue(true, (string) $method . ' passed');
         }
     }
 
@@ -70,47 +70,47 @@ public function testTryPrivate(): void
     {
         $router = Router::new(self::class);
 
-        $this->assertNotNull($router->match(Method::Get, '/private-route'));
+        self::assertNotNull($router->match(Method::Get, '/private-route'));
     }
 
     public function testMatchPublicStaticRoute(): void
     {
         $router = Router::new($this);
 
-        $this->assertNotNull($route = $router->match(Method::Get, '/public-static-route'));
-        $this->assertSame('public-static-route-result', $route());
+        self::assertNotNull($route = $router->match(Method::Get, '/public-static-route'));
+        self::assertSame('public-static-route-result', $route());
     }
 
     public function testMatchPublicStaticStaticRoute(): void
     {
         $router = Router::new(self::class);
 
-        $this->assertNotNull($route = $router->match(Method::Get, '/public-static-static-route'));
-        $this->assertSame('public-static-static-route-result', $route());
+        self::assertNotNull($route = $router->match(Method::Get, '/public-static-static-route'));
+        self::assertSame('public-static-static-route-result', $route());
     }
 
     public function testMatchPublicStaticRegexpRoute(): void
     {
         $router = Router::new(self::class);
 
-        $this->assertNotNull($route = $router->match(Method::Delete, '/item/123e4567-e89b-12d3-a456-426614174000'));
-        $this->assertSame('123e4567-e89b-12d3-a456-426614174000', $route());
+        self::assertNotNull($route = $router->match(Method::Delete, '/item/123e4567-e89b-12d3-a456-426614174000'));
+        self::assertSame('123e4567-e89b-12d3-a456-426614174000', $route());
     }
 
     public function testMatchPublicStaticRegexpRouteWithAdditionalArgs(): void
     {
         $router = Router::new(self::class);
 
-        $this->assertNotNull($route = $router->match(Method::Delete, '/item/123e4567-e89b-12d3-a456-426614174000'));
-        $this->assertSame('123e4567-e89b-12d3-a456-426614174000', $route(id: 'test'));
+        self::assertNotNull($route = $router->match(Method::Delete, '/item/123e4567-e89b-12d3-a456-426614174000'));
+        self::assertSame('123e4567-e89b-12d3-a456-426614174000', $route(id: 'test'));
     }
 
     public function testArgumentsCollision(): void
     {
         $router = Router::new(self::class);
 
-        $this->assertNotNull($route = $router->match(Method::Delete, '/item/123e4567-e89b-12d3-a456-426614174000'));
-        $this->assertSame('123e4567-e89b-12d3-a456-426614174000', $route(uuid: 'no-pasaran'));
+        self::assertNotNull($route = $router->match(Method::Delete, '/item/123e4567-e89b-12d3-a456-426614174000'));
+        self::assertSame('123e4567-e89b-12d3-a456-426614174000', $route(uuid: 'no-pasaran'));
     }
 
     #[StaticRoute(Method::Get, '/public-static-route')]
diff --git a/tests/Unit/Sender/Frontend/EventsStorageTest.php b/tests/Unit/Sender/Frontend/EventsStorageTest.php
index dabb22da..afa60b54 100644
--- a/tests/Unit/Sender/Frontend/EventsStorageTest.php
+++ b/tests/Unit/Sender/Frontend/EventsStorageTest.php
@@ -22,11 +22,11 @@ public function testMaxEventsLimit(): void
         $storage->add($e2 = $this->createEvent());
         $storage->add($e3 = $this->createEvent());
 
-        $this->assertCount(2, $storage);
+        self::assertCount(2, $storage);
         // In an ordered event sequence of adding events, the first event should be removed
-        $this->assertNull($storage->get($e1->uuid));
-        $this->assertNotNull($storage->get($e2->uuid));
-        $this->assertNotNull($storage->get($e3->uuid));
+        self::assertNull($storage->get($e1->uuid));
+        self::assertNotNull($storage->get($e2->uuid));
+        self::assertNotNull($storage->get($e3->uuid));
     }
 
     public function testMaxEventsLimitWithSort(): void
@@ -39,15 +39,15 @@ public function testMaxEventsLimitWithSort(): void
         $storage->add($e2 = $this->createEvent());
         $storage->add($e3 = $this->createEvent(timestamp: \microtime(true) - 1));
 
-        $this->assertCount(2, $storage);
+        self::assertCount(2, $storage);
         // new event should be added in order of timestamp, and then the first event should be removed
-        $this->assertNull($storage->get($e3->uuid));
-        $this->assertNotNull($storage->get($e1->uuid));
-        $this->assertNotNull($storage->get($e2->uuid));
+        self::assertNull($storage->get($e3->uuid));
+        self::assertNotNull($storage->get($e1->uuid));
+        self::assertNotNull($storage->get($e2->uuid));
         // Check order of events
         $events = \iterator_to_array($storage->getIterator(), false);
-        $this->assertSame($e2->uuid, $events[0]->uuid);
-        $this->assertSame($e1->uuid, $events[1]->uuid);
+        self::assertSame($e2->uuid, $events[0]->uuid);
+        self::assertSame($e1->uuid, $events[1]->uuid);
     }
 
     private function createEvent(
diff --git a/tests/Unit/Traffic/Dispatcher/HttpTest.php b/tests/Unit/Traffic/Dispatcher/HttpTest.php
index bda28112..58ef6f34 100644
--- a/tests/Unit/Traffic/Dispatcher/HttpTest.php
+++ b/tests/Unit/Traffic/Dispatcher/HttpTest.php
@@ -54,6 +54,6 @@ public static function detectProvider()
     public function testDetect(string $data, ?bool $expected): void
     {
         $dispatcher = new Http();
-        $this->assertSame($expected, $dispatcher->detect($data, new \DateTimeImmutable()));
+        self::assertSame($expected, $dispatcher->detect($data, new \DateTimeImmutable()));
     }
 }
diff --git a/tests/Unit/Traffic/Dispatcher/VarDumperTest.php b/tests/Unit/Traffic/Dispatcher/VarDumperTest.php
index 9ccb3a11..495a972d 100644
--- a/tests/Unit/Traffic/Dispatcher/VarDumperTest.php
+++ b/tests/Unit/Traffic/Dispatcher/VarDumperTest.php
@@ -28,7 +28,7 @@ public static function detectProvider(): iterable
     public function testDetect(string $data, ?bool $expected): void
     {
         $dispatcher = new VarDumper();
-        $this->assertSame($expected, $dispatcher->detect($data, new \DateTimeImmutable()));
+        self::assertSame($expected, $dispatcher->detect($data, new \DateTimeImmutable()));
     }
 
     public function testDispatchFramesTime(): void
diff --git a/tests/Unit/Traffic/Emitter/HttpTest.php b/tests/Unit/Traffic/Emitter/HttpTest.php
index 7f1d1d4e..54811027 100644
--- a/tests/Unit/Traffic/Emitter/HttpTest.php
+++ b/tests/Unit/Traffic/Emitter/HttpTest.php
@@ -59,8 +59,8 @@ static function () use ($response, $stream2): void {
         }
 
         // Check that the data is the same
-        $this->assertSame($data1, $data2);
-        $this->assertSame($content, $data1);
-        $this->assertSame($content, $data2);
+        self::assertSame($data1, $data2);
+        self::assertSame($content, $data1);
+        self::assertSame($content, $data2);
     }
 }
diff --git a/tests/Unit/Traffic/Message/Multipart/FieldTest.php b/tests/Unit/Traffic/Message/Multipart/FieldTest.php
index b8cf99ed..33352c6d 100644
--- a/tests/Unit/Traffic/Message/Multipart/FieldTest.php
+++ b/tests/Unit/Traffic/Message/Multipart/FieldTest.php
@@ -13,9 +13,9 @@ public function testGetters(): void
     {
         $field = new Field(['Foo' => 'Bar'], 'name', 'value');
 
-        $this->assertSame('name', $field->getName());
-        $this->assertSame('value', $field->getValue());
-        $this->assertSame('Bar', $field->getHeaderLine('foo'));
+        self::assertSame('name', $field->getName());
+        self::assertSame('value', $field->getValue());
+        self::assertSame('Bar', $field->getHeaderLine('foo'));
     }
 
     public function testWithHeader(): void
@@ -23,18 +23,18 @@ public function testWithHeader(): void
         $field = new Field(['Foo' => 'Bar'], 'name', 'value');
         $new = $field->withHeader('foo', 'baz');
 
-        $this->assertNotSame($field, $new);
-        $this->assertSame('Bar', $field->getHeaderLine('foo'));
-        $this->assertSame('baz', $new->getHeaderLine('foo'));
+        self::assertNotSame($field, $new);
+        self::assertSame('Bar', $field->getHeaderLine('foo'));
+        self::assertSame('baz', $new->getHeaderLine('foo'));
     }
 
     public function testFromArray(): void
     {
         $field = Field::fromArray(['headers' => ['Foo' => ['Bar', 'Baz']], 'value' => 'bar']);
 
-        $this->assertNull($field->getName());
-        $this->assertSame('bar', $field->getValue());
-        $this->assertSame(['Bar', 'Baz'], $field->getHeader('foo'));
+        self::assertNull($field->getName());
+        self::assertSame('bar', $field->getValue());
+        self::assertSame(['Bar', 'Baz'], $field->getHeader('foo'));
     }
 
     public function testSerializeAndUnserialize(): void
@@ -42,6 +42,6 @@ public function testSerializeAndUnserialize(): void
         $from = new Field(['Foo' => ['Bar', 'Baz']], 'message', 'foo bar baz');
         $to = Field::fromArray($from->jsonSerialize());
 
-        $this->assertEquals($from, $to);
+        self::assertEquals($from, $to);
     }
 }
diff --git a/tests/Unit/Traffic/Message/Multipart/FileTest.php b/tests/Unit/Traffic/Message/Multipart/FileTest.php
index 5f565e63..c9bf9992 100644
--- a/tests/Unit/Traffic/Message/Multipart/FileTest.php
+++ b/tests/Unit/Traffic/Message/Multipart/FileTest.php
@@ -14,9 +14,9 @@ public function testGetters(): void
     {
         $file = new File(['Foo' => 'Bar'], 'name', 'filename');
 
-        $this->assertSame('name', $file->getName());
-        $this->assertSame('filename', $file->getClientFilename());
-        $this->assertSame('Bar', $file->getHeaderLine('foo'));
+        self::assertSame('name', $file->getName());
+        self::assertSame('filename', $file->getClientFilename());
+        self::assertSame('Bar', $file->getHeaderLine('foo'));
     }
 
     public function testWithHeader(): void
@@ -24,9 +24,9 @@ public function testWithHeader(): void
         $file = new File(['Foo' => 'Bar'], 'name', 'filename');
         $new = $file->withHeader('foo', 'baz');
 
-        $this->assertNotSame($file, $new);
-        $this->assertSame('Bar', $file->getHeaderLine('foo'));
-        $this->assertSame('baz', $new->getHeaderLine('foo'));
+        self::assertNotSame($file, $new);
+        self::assertSame('Bar', $file->getHeaderLine('foo'));
+        self::assertSame('baz', $new->getHeaderLine('foo'));
     }
 
     public function testFromArray(): void
@@ -37,11 +37,11 @@ public function testFromArray(): void
             'size' => 10,
         ]);
 
-        $this->assertNull($field->getName());
-        $this->assertSame(10, $field->getSize());
-        $this->assertSame('bar.jpg', $field->getClientFilename());
-        $this->assertSame('image/jpeg', $field->getClientMediaType());
-        $this->assertSame(['Bar', 'Baz'], $field->getHeader('foo'));
+        self::assertNull($field->getName());
+        self::assertSame(10, $field->getSize());
+        self::assertSame('bar.jpg', $field->getClientFilename());
+        self::assertSame('image/jpeg', $field->getClientMediaType());
+        self::assertSame(['Bar', 'Baz'], $field->getHeader('foo'));
     }
 
     public function testSerializeAndUnserialize(): void
@@ -53,9 +53,9 @@ public function testSerializeAndUnserialize(): void
 
         $to = File::fromArray($from->jsonSerialize());
 
-        $this->assertSame($from->getHeaders(), $to->getHeaders());
-        $this->assertSame($from->getSize(), $to->getSize());
-        $this->assertSame($from->getClientFilename(), $to->getClientFilename());
-        $this->assertSame($from->getClientMediaType(), $to->getClientMediaType());
+        self::assertSame($from->getHeaders(), $to->getHeaders());
+        self::assertSame($from->getSize(), $to->getSize());
+        self::assertSame($from->getClientFilename(), $to->getClientFilename());
+        self::assertSame($from->getClientMediaType(), $to->getClientMediaType());
     }
 }
diff --git a/tests/Unit/Traffic/Parser/HttpParserTest.php b/tests/Unit/Traffic/Parser/HttpParserTest.php
index aa562d71..fbc27293 100644
--- a/tests/Unit/Traffic/Parser/HttpParserTest.php
+++ b/tests/Unit/Traffic/Parser/HttpParserTest.php
@@ -39,12 +39,12 @@ public function testSimpleGet(): void
 
         $request = $this->parseStream($body);
 
-        $this->assertSame('GET', $request->getMethod());
-        $this->assertSame('/foo/bar', $request->getUri()->getPath());
-        $this->assertSame('1.1', $request->getProtocolVersion());
-        $this->assertSame(['127.0.0.1:9912'], $request->getHeader('host'));
-        $this->assertSame(['ru-RU,ru;q=0.8,en-US;q=0.5,en;q=0.3'], $request->getHeader('accept-language'));
-        $this->assertSame([
+        self::assertSame('GET', $request->getMethod());
+        self::assertSame('/foo/bar', $request->getUri()->getPath());
+        self::assertSame('1.1', $request->getProtocolVersion());
+        self::assertSame(['127.0.0.1:9912'], $request->getHeader('host'));
+        self::assertSame(['ru-RU,ru;q=0.8,en-US;q=0.5,en;q=0.3'], $request->getHeader('accept-language'));
+        self::assertSame([
             'koa.sess' => 'Ijo4NjQwMDAwMH0=',
             'koa.sess.sig' => 'liV7oStLo',
             'csrf-token' => 'Gmch9',
@@ -75,12 +75,12 @@ public function testWrongCookie(): void
 
         $request = $this->parseStream($body);
 
-        $this->assertSame('GET', $request->getMethod());
-        $this->assertSame('/foo/bar', $request->getUri()->getPath());
-        $this->assertSame('1.1', $request->getProtocolVersion());
-        $this->assertSame(['127.0.0.1:9912'], $request->getHeader('host'));
-        $this->assertSame(['ru-RU,ru;q=0.8,en-US;q=0.5,en;q=0.3'], $request->getHeader('accept-language'));
-        $this->assertSame([
+        self::assertSame('GET', $request->getMethod());
+        self::assertSame('/foo/bar', $request->getUri()->getPath());
+        self::assertSame('1.1', $request->getProtocolVersion());
+        self::assertSame(['127.0.0.1:9912'], $request->getHeader('host'));
+        self::assertSame(['ru-RU,ru;q=0.8,en-US;q=0.5,en;q=0.3'], $request->getHeader('accept-language'));
+        self::assertSame([
             'csrf-token.sig' => 'X0fR',
         ], $request->getCookieParams());
     }
@@ -111,12 +111,12 @@ public function testPostUrlEncoded(): void
 
         $request = $this->parseStream($body);
 
-        $this->assertSame('POST', $request->getMethod());
-        $this->assertSame('/foo/bar', $request->getUri()->getPath());
-        $this->assertSame('1.1', $request->getProtocolVersion());
-        $this->assertSame(['foo.bar.com'], $request->getHeader('host'));
-        $this->assertSame('foo=bar&baz=qux&quux=corge+grault', $request->getBody()->__toString());
-        $this->assertSame(['foo' => 'bar', 'baz' => 'qux', 'quux' => 'corge grault'], $request->getParsedBody());
+        self::assertSame('POST', $request->getMethod());
+        self::assertSame('/foo/bar', $request->getUri()->getPath());
+        self::assertSame('1.1', $request->getProtocolVersion());
+        self::assertSame(['foo.bar.com'], $request->getHeader('host'));
+        self::assertSame('foo=bar&baz=qux&quux=corge+grault', $request->getBody()->__toString());
+        self::assertSame(['foo' => 'bar', 'baz' => 'qux', 'quux' => 'corge grault'], $request->getParsedBody());
     }
 
     public function testPostMultipartFormData(): void
@@ -161,26 +161,26 @@ public function testPostMultipartFormData(): void
 
         $request = $this->parseStream($headers . $body);
 
-        $this->assertSame('POST', $request->getMethod());
-        $this->assertSame('/send-message.html', $request->getUri()->getPath());
-        $this->assertSame('1.1', $request->getProtocolVersion());
-        $this->assertSame(['webmail.example.com'], $request->getHeader('host'));
+        self::assertSame('POST', $request->getMethod());
+        self::assertSame('/send-message.html', $request->getUri()->getPath());
+        self::assertSame('1.1', $request->getProtocolVersion());
+        self::assertSame(['webmail.example.com'], $request->getHeader('host'));
         // POST data
-        $this->assertEquals([
+        self::assertEquals([
             'Authors' => '@roxblnfk and @butschster',
             'MessageTitle' => 'Hello guys! The Buggregator is a great tool!',
             'MessageText' => 'Do you know that Buggregator could be called Deburger? But we decided to name it Buggregator.',
         ], $request->getParsedBody());
         // Uploaded files
-        $this->assertCount(2, $files = $request->getUploadedFiles());
+        self::assertCount(2, $files = $request->getUploadedFiles());
         /** @var UploadedFileInterface[] $files */
-        $this->assertSame('deburger.png', $files['AttachedFile1'][0]->getClientFilename());
-        $this->assertSame('image/png', $files['AttachedFile1'][0]->getClientMediaType());
-        $this->assertSame($file1, $files['AttachedFile1'][0]->getStream()->__toString());
+        self::assertSame('deburger.png', $files['AttachedFile1'][0]->getClientFilename());
+        self::assertSame('image/png', $files['AttachedFile1'][0]->getClientMediaType());
+        self::assertSame($file1, $files['AttachedFile1'][0]->getStream()->__toString());
 
-        $this->assertSame('buggregator.png', $files['AttachedFile2'][0]->getClientFilename());
-        $this->assertSame('image/png', $files['AttachedFile2'][0]->getClientMediaType());
-        $this->assertSame($file2, $files['AttachedFile2'][0]->getStream()->__toString());
+        self::assertSame('buggregator.png', $files['AttachedFile2'][0]->getClientFilename());
+        self::assertSame('image/png', $files['AttachedFile2'][0]->getClientMediaType());
+        self::assertSame($file2, $files['AttachedFile2'][0]->getStream()->__toString());
     }
 
     public function testGzippedBody(): void
diff --git a/tests/Unit/Traffic/Parser/MultipartBodyParserTest.php b/tests/Unit/Traffic/Parser/MultipartBodyParserTest.php
index b21e274a..001efcd8 100644
--- a/tests/Unit/Traffic/Parser/MultipartBodyParserTest.php
+++ b/tests/Unit/Traffic/Parser/MultipartBodyParserTest.php
@@ -43,9 +43,9 @@ public function testParse(): void
 
         $result = $this->parse($body, 'your-boundary');
 
-        $this->assertCount(2, $result);
-        $this->assertInstanceOf(Field::class, $result[0]);
-        $this->assertInstanceOf(Field::class, $result[1]);
+        self::assertCount(2, $result);
+        self::assertInstanceOf(Field::class, $result[0]);
+        self::assertInstanceOf(Field::class, $result[1]);
     }
 
     public function testWithFileAttach(): void
@@ -82,35 +82,35 @@ public function testWithFileAttach(): void
 
         $result = $this->parse($body, 'Asrf456BGe4h');
 
-        $this->assertCount(5, $result);
-        $this->assertInstanceOf(Field::class, $result[0]);
-        $this->assertInstanceOf(Field::class, $result[1]);
+        self::assertCount(5, $result);
+        self::assertInstanceOf(Field::class, $result[0]);
+        self::assertInstanceOf(Field::class, $result[1]);
 
         // POST data
-        $this->assertSame('Authors', $result[0]->getName());
-        $this->assertSame('@roxblnfk and @butschster', $result[0]->getValue());
-        $this->assertSame('MessageTitle', $result[1]->getName());
-        $this->assertSame('Hello guys! The Buggregator is a great tool!', $result[1]->getValue());
-        $this->assertSame('MessageText', $result[2]->getName());
-        $this->assertSame(
+        self::assertSame('Authors', $result[0]->getName());
+        self::assertSame('@roxblnfk and @butschster', $result[0]->getValue());
+        self::assertSame('MessageTitle', $result[1]->getName());
+        self::assertSame('Hello guys! The Buggregator is a great tool!', $result[1]->getValue());
+        self::assertSame('MessageText', $result[2]->getName());
+        self::assertSame(
             'Do you know that Buggregator could be called Deburger? But we decided to name it Buggregator.',
             $result[2]->getValue(),
         );
 
         $file = $result[3];
         // Uploaded files
-        $this->assertInstanceOf(File::class, $file);
-        $this->assertSame('AttachedFile1', $file->getName());
-        $this->assertSame('deburger.png', $file->getClientFilename());
-        $this->assertSame('image/png', $file->getClientMediaType());
-        $this->assertSame($file1, $file->getStream()->__toString());
+        self::assertInstanceOf(File::class, $file);
+        self::assertSame('AttachedFile1', $file->getName());
+        self::assertSame('deburger.png', $file->getClientFilename());
+        self::assertSame('image/png', $file->getClientMediaType());
+        self::assertSame($file1, $file->getStream()->__toString());
 
         $file = $result[4];
-        $this->assertInstanceOf(File::class, $file);
-        $this->assertSame('AttachedFile2', $file->getName());
-        $this->assertSame('buggregator.png', $file->getClientFilename());
-        $this->assertSame('image/png', $file->getClientMediaType());
-        $this->assertSame($file2, $file->getStream()->__toString());
+        self::assertInstanceOf(File::class, $file);
+        self::assertSame('AttachedFile2', $file->getName());
+        self::assertSame('buggregator.png', $file->getClientFilename());
+        self::assertSame('image/png', $file->getClientMediaType());
+        self::assertSame($file2, $file->getStream()->__toString());
     }
 
     private function makeStream(string $body): StreamInterface
diff --git a/tests/Unit/Traffic/Parser/SmtpParserTest.php b/tests/Unit/Traffic/Parser/SmtpParserTest.php
index f07b9137..7dd2b8fb 100644
--- a/tests/Unit/Traffic/Parser/SmtpParserTest.php
+++ b/tests/Unit/Traffic/Parser/SmtpParserTest.php
@@ -27,17 +27,17 @@ public function testParseSimpleBody(): void
             SMTP, 10);
         $message = $this->parse($data);
 
-        $this->assertSame(\implode('', $data), (string) $message->getBody());
-        $this->assertCount(1, $message->getMessages());
+        self::assertSame(\implode('', $data), (string) $message->getBody());
+        self::assertCount(1, $message->getMessages());
         // Check headers
-        $this->assertEquals([
+        self::assertEquals([
             'From' => ['Some User <someusername@somecompany.ru>'],
             'To' => ['User1 <user1@company.tld>'],
             'Subject' => ['Very important theme'],
             'Content-Type' => ['text/plain'],
         ], $message->getHeaders());
         // Check body
-        $this->assertSame('Hi!', $message->getMessages()[0]->getValue());
+        self::assertSame('Hi!', $message->getMessages()[0]->getValue());
     }
 
     public function testParseMultipart(): void
@@ -88,22 +88,22 @@ public function testParseMultipart(): void
         // Check contacts
 
         // Sender
-        $this->assertCount(2, $message->getSender());
-        $this->assertNull($message->getSender()[0]->name);
-        $this->assertSame('someusername@foo.bar', $message->getSender()[0]->email);
-        $this->assertNull($message->getSender()[1]->name);
-        $this->assertSame('sender@example.com', $message->getSender()[1]->email);
+        self::assertCount(2, $message->getSender());
+        self::assertNull($message->getSender()[0]->name);
+        self::assertSame('someusername@foo.bar', $message->getSender()[0]->email);
+        self::assertNull($message->getSender()[1]->name);
+        self::assertSame('sender@example.com', $message->getSender()[1]->email);
         // BCC
-        $this->assertCount(2, $message->getBcc());
-        $this->assertNull($message->getBcc()[0]->name);
-        $this->assertSame('user1@company.tld', $message->getBcc()[0]->email);
-        $this->assertNull($message->getBcc()[1]->name);
-        $this->assertSame('user2@company.tld', $message->getBcc()[1]->email);
-
-        $this->assertSame(\implode('', $data), (string) $message->getBody());
-        $this->assertCount(3, $message->getMessages());
+        self::assertCount(2, $message->getBcc());
+        self::assertNull($message->getBcc()[0]->name);
+        self::assertSame('user1@company.tld', $message->getBcc()[0]->email);
+        self::assertNull($message->getBcc()[1]->name);
+        self::assertSame('user2@company.tld', $message->getBcc()[1]->email);
+
+        self::assertSame(\implode('', $data), (string) $message->getBody());
+        self::assertCount(3, $message->getMessages());
         // Check headers
-        $this->assertEquals([
+        self::assertEquals([
             'From' => ['sender@example.com'],
             'To' => ['recipient@example.com'],
             'Subject' => ['Multipart Email Example'],
@@ -113,40 +113,40 @@ public function testParseMultipart(): void
         // Check bodies
 
         // Body 0
-        $this->assertSame(
+        self::assertSame(
             "Plain text email goes here!\r\nThis is the fallback if email client does not support HTML\r\n",
             $message->getMessages()[0]->getValue(),
         );
-        $this->assertEquals([
+        self::assertEquals([
             'Content-Type' => ['text/plain; charset="utf-8"'],
             'Content-Transfer-Encoding' => ['quoted-printable'],
             'Content-Disposition' => ['inline'],
         ], $message->getMessages()[0]->getHeaders());
 
         // Body 1
-        $this->assertSame(
+        self::assertSame(
             "<h1>This is the HTML Section!</h1>\r\n<p>This is what displays in most modern email clients</p>\r\n",
             $message->getMessages()[1]->getValue(),
         );
-        $this->assertEquals([
+        self::assertEquals([
             'Content-Type' => ['text/html; charset="utf-8"'],
             'Content-Transfer-Encoding' => ['quoted-printable'],
             'Content-Disposition' => ['inline'],
         ], $message->getMessages()[1]->getHeaders());
 
         // Body 2
-        $this->assertSame(
+        self::assertSame(
             "<b>Apple Watch formatted content</b>\r\n",
             $message->getMessages()[2]->getValue(),
         );
-        $this->assertEquals([
+        self::assertEquals([
             'Content-Type' => ['text/watch-html; charset="utf-8"'],
             'Content-Transfer-Encoding' => ['quoted-printable'],
             'Content-Disposition' => ['inline'],
         ], $message->getMessages()[2]->getHeaders());
 
         // Check attachments
-        $this->assertCount(1, $message->getAttachments());
+        self::assertCount(1, $message->getAttachments());
     }
 
     private function parse(array|string $body, array $protocol = []): Message\Smtp
diff --git a/tests/Unit/Traffic/Proto/Server/Version/V1Test.php b/tests/Unit/Traffic/Proto/Server/Version/V1Test.php
index 15b002fc..b456efba 100644
--- a/tests/Unit/Traffic/Proto/Server/Version/V1Test.php
+++ b/tests/Unit/Traffic/Proto/Server/Version/V1Test.php
@@ -24,7 +24,7 @@ public function testIsSuppoerted(string $payload, bool $isSupported): void
     {
         $decoder = new V1();
 
-        $this->assertSame($isSupported, $decoder->isSupport($payload));
+        self::assertSame($isSupported, $decoder->isSupport($payload));
     }
 
     public function testDecode(): void
@@ -33,9 +33,9 @@ public function testDecode(): void
 
         $request = $decoder->decode('1|0.1|9a06581c-3bec-4cf1-8412-b2a40bb36a76|[{},{}]');
 
-        $this->assertSame(1, $request->protocol);
-        $this->assertSame('0.1', $request->client);
-        $this->assertSame('9a06581c-3bec-4cf1-8412-b2a40bb36a76', $request->uuid);
-        $this->assertSame('[{},{}]', $request->payload);
+        self::assertSame(1, $request->protocol);
+        self::assertSame('0.1', $request->client);
+        self::assertSame('9a06581c-3bec-4cf1-8412-b2a40bb36a76', $request->uuid);
+        self::assertSame('[{},{}]', $request->payload);
     }
 }