diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 00000000..1ef8ea08
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,4 @@
+/build/
+/composer.lock
+/.php_cs.cache
+/vendor/
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 6158748d..399f0328 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -16,20 +16,18 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php_version: [7.1, 7.2, 7.3, 7.4]
-        task: ['test', 'test-lowest']
+        php_version: ["7.1", "7.2", "7.3", "7.4"]
     steps:
       - uses: actions/checkout@v4
       - name: Run tests
-        run: make PHP_VERSION=${{ matrix.php_version }} ${{ matrix.task }}
+        run: make PHP_VERSION=${{ matrix.php_version }} test
   tests-future-versions:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php_version: [8.0, 8.1, 8.2, 8.3]
-        task: ['test', 'test-lowest']
+        php_version: ["8.0", "8.1", "8.2", "8.3"]
     steps:
       - uses: actions/checkout@v4
       - name: Run tests against all major versions of PHP
-        run: make PHP_VERSION=${{ matrix.php_version }} ${{ matrix.task }}
+        run: make PHP_VERSION=${{ matrix.php_version }} test
         continue-on-error: true
diff --git a/Dockerfile b/Dockerfile
index 3bd78acb..3ed8688e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,12 @@
-ARG PHP_VERSION=7.4
+ARG PHP_VERSION=latest
 FROM php:${PHP_VERSION}
 
 RUN apt-get update && apt-get install -y git unzip && rm -rf /var/lib/apt/lists/*
 COPY --from=composer:2.2 /usr/bin/composer /usr/bin/composer
+
+WORKDIR /code
+
+COPY composer.json composer.json
+RUN composer install
+
+COPY . .
diff --git a/Makefile b/Makefile
index 5cef6930..2fabf9f0 100644
--- a/Makefile
+++ b/Makefile
@@ -4,31 +4,27 @@ build:
 	docker buildx build --build-arg=PHP_VERSION=$(PHP_VERSION) -t php-composer:$(PHP_VERSION) .
 
 lint: build
-	docker run --rm -v ./:/code -v/code/vendor php-composer:$(PHP_VERSION) bash -c 'cd /code && composer update && vendor/bin/phpcs --standard=phpcs.xml.dist --warning-severity=0 -p src/ test/'
+	docker run --rm -v ./:/code -v/code/vendor php-composer:$(PHP_VERSION) bash -c 'vendor/bin/phpcs --standard=phpcs.xml.dist --warning-severity=0 -p src/ scripts/ test/'
 
 test: build lint
-	docker run --rm -v ./:/code -e dependencies=highest -v/code/vendor php-composer:$(PHP_VERSION) bash -c 'cd /code && composer update && ./project_tests.sh'
-
-test-lowest: build lint
-	docker run --rm -v ./:/code -e dependencies=lowest -v/code/vendor php-composer:$(PHP_VERSION) bash -c 'cd /code && ./project_tests.sh'
-
+	docker run --rm -v ./:/code -v/code/vendor php-composer:$(PHP_VERSION) bash -c './project_tests.sh'
 
 test-7.1:
-	@$(MAKE) PHP_VERSION=7.1 test test-lowest
+	@$(MAKE) PHP_VERSION=7.1 test
 test-7.2:
-	@$(MAKE) PHP_VERSION=7.2 test test-lowest
+	@$(MAKE) PHP_VERSION=7.2 test
 test-7.3:
-	@$(MAKE) PHP_VERSION=7.3 test test-lowest
+	@$(MAKE) PHP_VERSION=7.3 test
 test-7.4:
-	@$(MAKE) PHP_VERSION=7.4 test test-lowest
+	@$(MAKE) PHP_VERSION=7.4 test
 test-8.0:
-	@$(MAKE) PHP_VERSION=8.0 test test-lowest
+	@$(MAKE) PHP_VERSION=8.0 test
 test-8.1:
-	@$(MAKE) PHP_VERSION=8.1 test test-lowest
+	@$(MAKE) PHP_VERSION=8.1 test
 test-8.2:
-	@$(MAKE) PHP_VERSION=8.2 test test-lowest
+	@$(MAKE) PHP_VERSION=8.2 test
 test-8.3:
-	@$(MAKE) PHP_VERSION=8.3 test test-lowest
+	@$(MAKE) PHP_VERSION=8.3 test
 
 test-all: test-7.1 test-7.2 test-7.3 test-7.4 test-8.0 test-8.1 test-8.2 test-8.3
 
diff --git a/project_tests.sh b/project_tests.sh
index 4470a220..6a639985 100755
--- a/project_tests.sh
+++ b/project_tests.sh
@@ -2,12 +2,5 @@
 #!/bin/bash
 set -e
 
-: "${dependencies:?Need to set dependencies environment variable}"
-if [ "$dependencies" = "lowest" ]; then
-    composer update --prefer-lowest --no-interaction
-    vendor/bin/phpcs --standard=phpcs.xml.dist --warning-severity=0 -p src/
-    vendor/bin/phpcs --standard=phpcs.xml.dist --warning-severity=0 -p scripts/ test/
-else
-    composer update --no-interaction
-fi
+vendor/bin/phpcs --standard=phpcs.xml.dist --warning-severity=0 -p src/ scripts/ test/
 vendor/bin/phpunit --log-junit="build/${dependencies}-phpunit.xml"