diff --git a/features/reinstall-extensions.feature b/features/reinstall-extensions.feature
new file mode 100644
index 00000000..f5b643be
--- /dev/null
+++ b/features/reinstall-extensions.feature
@@ -0,0 +1,25 @@
+Feature: Extensions can be re-installed with PIE, but only if needed
+
+  # pie download <ext> && pie install <ext>
+  Example: Installing a previously downloaded extension should install the extension
+    Given an extension was previously downloaded but not built
+    When I run a command to install an extension
+    Then the extension should have been installed and enabled
+
+  # pie build <ext> && pie install <ext>
+  Example: Installing a previously built extension should install the extension
+    Given an extension was previously built but not installed
+    When I run a command to install an extension
+    Then the extension should have been installed and enabled
+
+  # pie install <ext> && pie install <ext>
+  Example: Re-installing an existing extension is a no-op
+    Given an extension was previously installed and enabled
+    When I run a command to install an extension
+    Then the extension should not have been re-installed
+
+  # pie install <ext> && pie install --force <ext>
+  Example: Forcefully re-installing an existing extension should re-install the extension
+    Given an extension was previously installed and enabled
+    When I run a command to forcefully install an extension
+    Then the extension should have been installed and enabled
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 7a81d09b..19da6192 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -240,18 +240,6 @@ parameters:
 			count: 2
 			path: test/integration/Command/InstallCommandTest.php
 
-		-
-			message: '#^Call to function assert\(\) with true will always evaluate to true\.$#'
-			identifier: function.alreadyNarrowedType
-			count: 1
-			path: test/integration/Command/InstallCommandTest.php
-
-		-
-			message: '#^Call to function is_string\(\) with non\-empty\-string will always evaluate to true\.$#'
-			identifier: function.alreadyNarrowedType
-			count: 1
-			path: test/integration/Command/InstallCommandTest.php
-
 		-
 			message: '#^Call to function assert\(\) with true will always evaluate to true\.$#'
 			identifier: function.alreadyNarrowedType
diff --git a/src/Command/ShowCommand.php b/src/Command/ShowCommand.php
index c291dc6a..ec457f09 100644
--- a/src/Command/ShowCommand.php
+++ b/src/Command/ShowCommand.php
@@ -8,7 +8,6 @@
 use Composer\IO\NullIO;
 use Php\Pie\ComposerIntegration\PieComposerFactory;
 use Php\Pie\ComposerIntegration\PieComposerRequest;
-use Php\Pie\ComposerIntegration\PieInstalledJsonMetadataKeys;
 use Php\Pie\DependencyResolver\BundledPhpExtensionRefusal;
 use Php\Pie\DependencyResolver\Package;
 use Php\Pie\DependencyResolver\RequestedPackageAndVersion;
@@ -33,7 +32,6 @@
 use function rtrim;
 use function sprintf;
 
-/** @phpstan-import-type PieMetadata from PieInstalledJsonMetadataKeys */
 #[AsCommand(
     name: 'show',
     description: 'List the installed modules and their versions.',
diff --git a/src/ComposerIntegration/AddInstalledJsonMetadata.php b/src/ComposerIntegration/AddInstalledJsonMetadata.php
new file mode 100644
index 00000000..b829d2e0
--- /dev/null
+++ b/src/ComposerIntegration/AddInstalledJsonMetadata.php
@@ -0,0 +1,130 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Php\Pie\ComposerIntegration;
+
+use Composer\Package\CompleteAliasPackage;
+use Composer\Package\CompletePackageInterface;
+use Composer\PartialComposer;
+use Php\Pie\File\BinaryFile;
+use Webmozart\Assert\Assert;
+
+use function array_merge;
+use function implode;
+
+/** @internal This is not public API for PIE, so should not be depended upon unless you accept the risk of BC breaks */
+class AddInstalledJsonMetadata
+{
+    public function addDownloadMetadata(
+        PartialComposer $composer,
+        PieComposerRequest $composerRequest,
+        CompletePackageInterface $composerPackage,
+    ): void {
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_TARGET_PLATFORM_PHP_PATH,
+            $composerRequest->targetPlatform->phpBinaryPath->phpBinaryPath,
+        );
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_TARGET_PLATFORM_PHP_CONFIG_PATH,
+            $composerRequest->targetPlatform->phpBinaryPath->phpConfigPath(),
+        );
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_TARGET_PLATFORM_PHP_VERSION,
+            $composerRequest->targetPlatform->phpBinaryPath->version(),
+        );
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_TARGET_PLATFORM_PHP_THREAD_SAFETY,
+            $composerRequest->targetPlatform->threadSafety->name,
+        );
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_TARGET_PLATFORM_PHP_WINDOWS_COMPILER,
+            $composerRequest->targetPlatform->windowsCompiler?->name,
+        );
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_TARGET_PLATFORM_ARCHITECTURE,
+            $composerRequest->targetPlatform->architecture->name,
+        );
+    }
+
+    public function addBuildMetadata(
+        PartialComposer $composer,
+        PieComposerRequest $composerRequest,
+        CompletePackageInterface $composerPackage,
+        BinaryFile $builtBinary,
+    ): void {
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_CONFIGURE_OPTIONS,
+            implode(' ', $composerRequest->configureOptions),
+        );
+
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_PHPIZE_BINARY,
+            $composerRequest->targetPlatform->phpizePath->phpizeBinaryPath ?? null,
+        );
+
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_BUILT_BINARY,
+            $builtBinary->filePath,
+        );
+
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_BINARY_CHECKSUM,
+            $builtBinary->checksum,
+        );
+    }
+
+    public function addInstallMetadata(
+        PartialComposer $composer,
+        CompletePackageInterface $composerPackage,
+        BinaryFile $installedBinary,
+    ): void {
+        $this->addPieMetadata(
+            $composer,
+            $composerPackage,
+            InstalledJsonMetadata::KEY_INSTALLED_BINARY,
+            $installedBinary->filePath,
+        );
+    }
+
+    /** @param InstalledJsonMetadata::KEY_* $key */
+    private function addPieMetadata(
+        PartialComposer $composer,
+        CompletePackageInterface $composerPackage,
+        string $key,
+        string|null $value,
+    ): void {
+        $localRepositoryPackage = $composer
+            ->getRepositoryManager()
+            ->getLocalRepository()
+            ->findPackages($composerPackage->getName())[0];
+
+        if ($localRepositoryPackage instanceof CompleteAliasPackage) {
+            $localRepositoryPackage = $localRepositoryPackage->getAliasOf();
+        }
+
+        Assert::methodExists($localRepositoryPackage, 'setExtra');
+
+        $localRepositoryPackage->setExtra(array_merge($localRepositoryPackage->getExtra(), [$key => $value]));
+    }
+}
diff --git a/src/ComposerIntegration/ComposerIntegrationHandler.php b/src/ComposerIntegration/ComposerIntegrationHandler.php
index 6a13b6b3..6557487f 100644
--- a/src/ComposerIntegration/ComposerIntegrationHandler.php
+++ b/src/ComposerIntegration/ComposerIntegrationHandler.php
@@ -7,13 +7,20 @@
 use Composer\Composer;
 use Composer\Filter\PlatformRequirementFilter\PlatformRequirementFilterFactory;
 use Composer\Installer;
+use Composer\IO\IOInterface;
+use Composer\Package\CompleteAliasPackage;
+use Composer\Package\CompletePackageInterface;
 use Php\Pie\DependencyResolver\Package;
 use Php\Pie\DependencyResolver\RequestedPackageAndVersion;
+use Php\Pie\ExtensionName;
 use Php\Pie\Platform;
 use Php\Pie\Platform\TargetPlatform;
+use Php\Pie\Util\Emoji;
 use Psr\Container\ContainerInterface;
 
+use function assert;
 use function file_exists;
+use function sprintf;
 
 /** @internal This is not public API for PIE, so should not be depended upon unless you accept the risk of BC breaks */
 class ComposerIntegrationHandler
@@ -63,9 +70,61 @@ public function runInstall(
         // Refresh the Composer instance so it re-reads the updated pie.json
         $composer = PieComposerFactory::recreatePieComposer($this->container, $composer);
 
-        // Removing the package from the local repository will trick Composer into "re-installing" it :)
-        foreach ($composer->getRepositoryManager()->getLocalRepository()->findPackages($requestedPackageAndVersion->package) as $pkg) {
-            $composer->getRepositoryManager()->getLocalRepository()->removePackage($pkg);
+        foreach ($composer->getRepositoryManager()->getLocalRepository()->getPackages() as $localRepoPackage) {
+            $extName = ExtensionName::determineFromComposerPackage($localRepoPackage);
+
+            if ($localRepoPackage instanceof CompleteAliasPackage) {
+                $localRepoPackage = $localRepoPackage->getAliasOf();
+            }
+
+            assert($localRepoPackage instanceof CompletePackageInterface);
+            $piePackage            = Package::fromComposerCompletePackage($localRepoPackage);
+            $installedJsonMetadata = $piePackage->installedJsonMetadata();
+            $status                = $piePackage->verifyPackageStatus($targetPlatform);
+
+            $this->arrayCollectionIo->write(sprintf(
+                'Install status %s (%s) status=%s',
+                $localRepoPackage->getName(),
+                $extName->name(),
+                $status->description(),
+            ), verbosity: IOInterface::VERY_VERBOSE);
+
+            if ($status->isVerified() && ! $forceInstallPackageVersion) {
+                $this->arrayCollectionIo->write(sprintf(
+                    '%s PIE package %s (%s) is already installed and verified.',
+                    Emoji::GREEN_CHECKMARK,
+                    $localRepoPackage->getName(),
+                    $extName->name(),
+                ), verbosity: IOInterface::QUIET);
+                continue;
+            }
+
+            if (! $installedJsonMetadata->isInstalled() && $installedJsonMetadata->isBuilt()) {
+                $this->arrayCollectionIo->write(sprintf(
+                    '%s PIE package %s (%s) was previously built but not installed.',
+                    Emoji::INFO,
+                    $localRepoPackage->getName(),
+                    $extName->name(),
+                ), verbosity: IOInterface::VERBOSE);
+            }
+
+            if (! $installedJsonMetadata->isInstalled() && ! $installedJsonMetadata->isBuilt() && $installedJsonMetadata->isDownloaded()) {
+                $this->arrayCollectionIo->write(sprintf(
+                    '%s PIE package %s (%s) was previously downloaded but not built.',
+                    Emoji::INFO,
+                    $localRepoPackage->getName(),
+                    $extName->name(),
+                ), verbosity: IOInterface::VERBOSE);
+            }
+
+            $this->arrayCollectionIo->write(sprintf(
+                '%s Package status of %s (%s) is not yet verified, adding to install candidates: %s',
+                Emoji::WARNING,
+                $localRepoPackage->getName(),
+                $extName->name(),
+                $status->description(),
+            ));
+            $composer->getRepositoryManager()->getLocalRepository()->removePackage($localRepoPackage);
         }
 
         $composerInstaller = PieComposerInstaller::createWithPhpBinary(
diff --git a/src/ComposerIntegration/InstallAndBuildProcess.php b/src/ComposerIntegration/InstallAndBuildProcess.php
index 69985a78..45a97ab3 100644
--- a/src/ComposerIntegration/InstallAndBuildProcess.php
+++ b/src/ComposerIntegration/InstallAndBuildProcess.php
@@ -20,7 +20,7 @@ class InstallAndBuildProcess
     public function __construct(
         private readonly Build $pieBuild,
         private readonly Install $pieInstall,
-        private readonly InstalledJsonMetadata $installedJsonMetadata,
+        private readonly AddInstalledJsonMetadata $addInstalledJsonMetadata,
         private readonly PlaceholderReplacer $placeholderReplacer,
     ) {
     }
@@ -50,7 +50,7 @@ public function __invoke(
             $downloadedPackage,
         );
 
-        $this->installedJsonMetadata->addDownloadMetadata(
+        $this->addInstalledJsonMetadata->addDownloadMetadata(
             $composer,
             $composerRequest,
             $composerPackage,
@@ -65,7 +65,7 @@ public function __invoke(
                 $io,
             );
 
-            $this->installedJsonMetadata->addBuildMetadata(
+            $this->addInstalledJsonMetadata->addBuildMetadata(
                 $composer,
                 $composerRequest,
                 $composerPackage,
@@ -77,7 +77,7 @@ public function __invoke(
             return;
         }
 
-        $this->installedJsonMetadata->addInstallMetadata(
+        $this->addInstalledJsonMetadata->addInstallMetadata(
             $composer,
             $composerPackage,
             ($this->pieInstall)(
diff --git a/src/ComposerIntegration/InstalledJsonMetadata.php b/src/ComposerIntegration/InstalledJsonMetadata.php
index 77a35fb5..35d81159 100644
--- a/src/ComposerIntegration/InstalledJsonMetadata.php
+++ b/src/ComposerIntegration/InstalledJsonMetadata.php
@@ -5,120 +5,182 @@
 namespace Php\Pie\ComposerIntegration;
 
 use Composer\Package\CompletePackageInterface;
-use Composer\PartialComposer;
-use Php\Pie\ComposerIntegration\PieInstalledJsonMetadataKeys as MetadataKey;
-use Php\Pie\File\BinaryFile;
-use Webmozart\Assert\Assert;
 
-use function array_merge;
-use function implode;
+use function array_key_exists;
+use function is_string;
 
-/** @internal This is not public API for PIE, so should not be depended upon unless you accept the risk of BC breaks */
-class InstalledJsonMetadata
+/**
+ * @internal This is not public API for PIE, so should not be depended upon unless you accept the risk of BC breaks
+ *
+ * @phpstan-type PieMetadata = array{
+ *     pie-target-platform-php-path?: non-empty-string,
+ *     pie-target-platform-php-config-path?: non-empty-string,
+ *     pie-target-platform-php-version?: non-empty-string,
+ *     pie-target-platform-php-thread-safety?: non-empty-string,
+ *     pie-target-platform-php-windows-compiler?: non-empty-string,
+ *     pie-target-platform-architecture?: non-empty-string,
+ *     pie-configure-options?: non-empty-string,
+ *     pie-built-binary?: non-empty-string,
+ *     pie-installed-binary-checksum?: non-empty-string,
+ *     pie-installed-binary?: non-empty-string,
+ *     pie-phpize-binary?: non-empty-string,
+ * }
+ */
+final class InstalledJsonMetadata
 {
-    public function addDownloadMetadata(
-        PartialComposer $composer,
-        PieComposerRequest $composerRequest,
-        CompletePackageInterface $composerPackage,
-    ): void {
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::TargetPlatformPhpPath,
-            $composerRequest->targetPlatform->phpBinaryPath->phpBinaryPath,
-        );
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::TargetPlatformPhpConfigPath,
-            $composerRequest->targetPlatform->phpBinaryPath->phpConfigPath(),
-        );
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::TargetPlatformPhpVersion,
-            $composerRequest->targetPlatform->phpBinaryPath->version(),
-        );
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::TargetPlatformPhpThreadSafety,
-            $composerRequest->targetPlatform->threadSafety->name,
-        );
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::TargetPlatformPhpWindowsCompiler,
-            $composerRequest->targetPlatform->windowsCompiler?->name,
-        );
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::TargetPlatformArchitecture,
-            $composerRequest->targetPlatform->architecture->name,
-        );
-    }
-
-    public function addBuildMetadata(
-        PartialComposer $composer,
-        PieComposerRequest $composerRequest,
-        CompletePackageInterface $composerPackage,
-        BinaryFile $builtBinary,
-    ): void {
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::ConfigureOptions,
-            implode(' ', $composerRequest->configureOptions),
-        );
-
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::PhpizeBinary,
-            $composerRequest->targetPlatform->phpizePath->phpizeBinaryPath ?? null,
-        );
-
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::BuiltBinary,
-            $builtBinary->filePath,
-        );
-
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::BinaryChecksum,
-            $builtBinary->checksum,
-        );
-    }
-
-    public function addInstallMetadata(
-        PartialComposer $composer,
-        CompletePackageInterface $composerPackage,
-        BinaryFile $installedBinary,
-    ): void {
-        $this->addPieMetadata(
-            $composer,
-            $composerPackage,
-            MetadataKey::InstalledBinary,
-            $installedBinary->filePath,
-        );
-    }
-
-    private function addPieMetadata(
-        PartialComposer $composer,
-        CompletePackageInterface $composerPackage,
-        MetadataKey $key,
-        string|null $value,
-    ): void {
-        $localRepositoryPackage = $composer
-            ->getRepositoryManager()
-            ->getLocalRepository()
-            ->findPackages($composerPackage->getName())[0];
-        Assert::methodExists($localRepositoryPackage, 'setExtra');
-
-        $localRepositoryPackage->setExtra(array_merge($localRepositoryPackage->getExtra(), [$key->value => $value]));
+    public const KEY_TARGET_PLATFORM_PHP_PATH             = 'pie-target-platform-php-path';
+    public const KEY_TARGET_PLATFORM_PHP_CONFIG_PATH      = 'pie-target-platform-php-config-path';
+    public const KEY_TARGET_PLATFORM_PHP_VERSION          = 'pie-target-platform-php-version';
+    public const KEY_TARGET_PLATFORM_PHP_THREAD_SAFETY    = 'pie-target-platform-php-thread-safety';
+    public const KEY_TARGET_PLATFORM_PHP_WINDOWS_COMPILER = 'pie-target-platform-php-windows-compiler';
+    public const KEY_TARGET_PLATFORM_ARCHITECTURE         = 'pie-target-platform-architecture';
+    public const KEY_CONFIGURE_OPTIONS                    = 'pie-configure-options';
+    public const KEY_BUILT_BINARY                         = 'pie-built-binary';
+    public const KEY_BINARY_CHECKSUM                      = 'pie-installed-binary-checksum';
+    public const KEY_INSTALLED_BINARY                     = 'pie-installed-binary';
+    public const KEY_PHPIZE_BINARY                        = 'pie-phpize-binary';
+
+    private const ALL_KEYS = [
+        self::KEY_TARGET_PLATFORM_PHP_PATH,
+        self::KEY_TARGET_PLATFORM_PHP_CONFIG_PATH,
+        self::KEY_TARGET_PLATFORM_PHP_VERSION,
+        self::KEY_TARGET_PLATFORM_PHP_THREAD_SAFETY,
+        self::KEY_TARGET_PLATFORM_PHP_WINDOWS_COMPILER,
+        self::KEY_TARGET_PLATFORM_ARCHITECTURE,
+        self::KEY_CONFIGURE_OPTIONS,
+        self::KEY_BUILT_BINARY,
+        self::KEY_BINARY_CHECKSUM,
+        self::KEY_INSTALLED_BINARY,
+        self::KEY_PHPIZE_BINARY,
+    ];
+
+    /** @param PieMetadata $values */
+    private function __construct(private readonly array $values)
+    {
+    }
+
+    /** @param PieMetadata $values */
+    public static function fromArray(array $values): self
+    {
+        return new self($values);
+    }
+
+    public static function fromComposerPackage(CompletePackageInterface $composerPackage): self
+    {
+        $composerPackageExtras = $composerPackage->getExtra();
+
+        $onlyPieExtras = [];
+
+        foreach (self::ALL_KEYS as $key) {
+            if (
+                ! array_key_exists($key, $composerPackageExtras)
+                || ! is_string($composerPackageExtras[$key])
+                || $composerPackageExtras[$key] === ''
+            ) {
+                continue;
+            }
+
+            $onlyPieExtras[$key] = $composerPackageExtras[$key];
+        }
+
+        return new self($onlyPieExtras);
+    }
+
+    /** @return PieMetadata */
+    public function all(): array
+    {
+        return $this->values;
+    }
+
+    /** @return non-empty-string|null */
+    private function nonEmptyStringOrNull(string $key): string|null
+    {
+        return array_key_exists($key, $this->values)
+            ? $this->values[$key]
+            : null;
+    }
+
+    /** @return non-empty-string|null */
+    public function targetPlatformPhpPath(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_TARGET_PLATFORM_PHP_PATH);
+    }
+
+    /** @return non-empty-string|null */
+    public function targetPlatformPhpConfigPath(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_TARGET_PLATFORM_PHP_CONFIG_PATH);
+    }
+
+    /** @return non-empty-string|null */
+    public function targetPlatformPhpVersion(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_TARGET_PLATFORM_PHP_VERSION);
+    }
+
+    /** @return non-empty-string|null */
+    public function targetPlatformPhpThreadSafety(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_TARGET_PLATFORM_PHP_THREAD_SAFETY);
+    }
+
+    /** @return non-empty-string|null */
+    public function targetPlatformPhpWindowsCompiler(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_TARGET_PLATFORM_PHP_WINDOWS_COMPILER);
+    }
+
+    /** @return non-empty-string|null */
+    public function targetPlatformArchitecture(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_TARGET_PLATFORM_ARCHITECTURE);
+    }
+
+    /** @return non-empty-string|null */
+    public function configureOptions(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_CONFIGURE_OPTIONS);
+    }
+
+    /** @return non-empty-string|null */
+    public function builtBinary(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_BUILT_BINARY);
+    }
+
+    /** @return non-empty-string|null */
+    public function binaryChecksum(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_BINARY_CHECKSUM);
+    }
+
+    /** @return non-empty-string|null */
+    public function installedBinary(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_INSTALLED_BINARY);
+    }
+
+    /** @return non-empty-string|null */
+    public function phpizeBinary(): string|null
+    {
+        return $this->nonEmptyStringOrNull(self::KEY_PHPIZE_BINARY);
+    }
+
+    /** Has this package been downloaded, according to the metadata? (note: does not verifiy it is STILL downloaded - especially if vendor cleanup happened!) */
+    public function isDownloaded(): bool
+    {
+        return $this->targetPlatformPhpVersion() !== null;
+    }
+
+    /** Has this package been built, according to the metadata? (note: does not verify it is STILL built) */
+    public function isBuilt(): bool
+    {
+        return $this->isDownloaded() && $this->builtBinary() !== null;
+    }
+
+    /** Has this package been installed, according to the metadata (note: not verify it is STILL installed/verified) */
+    public function isInstalled(): bool
+    {
+        return $this->isBuilt() && $this->installedBinary() !== null;
     }
 }
diff --git a/src/ComposerIntegration/PieInstalledJsonMetadataKeys.php b/src/ComposerIntegration/PieInstalledJsonMetadataKeys.php
deleted file mode 100644
index e93210f8..00000000
--- a/src/ComposerIntegration/PieInstalledJsonMetadataKeys.php
+++ /dev/null
@@ -1,65 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Php\Pie\ComposerIntegration;
-
-use Composer\Package\CompletePackageInterface;
-
-use function array_column;
-use function array_key_exists;
-use function is_string;
-
-/**
- * @internal This is not public API for PIE, so should not be depended upon unless you accept the risk of BC breaks
- *
- * @phpstan-type PieMetadata = array{
- *     pie-target-platform-php-path?: non-empty-string,
- *     pie-target-platform-php-config-path?: non-empty-string,
- *     pie-target-platform-php-version?: non-empty-string,
- *     pie-target-platform-php-thread-safety?: non-empty-string,
- *     pie-target-platform-php-windows-compiler?: non-empty-string,
- *     pie-target-platform-architecture?: non-empty-string,
- *     pie-configure-options?: non-empty-string,
- *     pie-built-binary?: non-empty-string,
- *     pie-installed-binary-checksum?: non-empty-string,
- *     pie-installed-binary?: non-empty-string,
- *     pie-phpize-binary?: non-empty-string,
- * }
- */
-enum PieInstalledJsonMetadataKeys: string
-{
-    case TargetPlatformPhpPath            = 'pie-target-platform-php-path';
-    case TargetPlatformPhpConfigPath      = 'pie-target-platform-php-config-path';
-    case TargetPlatformPhpVersion         = 'pie-target-platform-php-version';
-    case TargetPlatformPhpThreadSafety    = 'pie-target-platform-php-thread-safety';
-    case TargetPlatformPhpWindowsCompiler = 'pie-target-platform-php-windows-compiler';
-    case TargetPlatformArchitecture       = 'pie-target-platform-architecture';
-    case ConfigureOptions                 = 'pie-configure-options';
-    case BuiltBinary                      = 'pie-built-binary';
-    case BinaryChecksum                   = 'pie-installed-binary-checksum';
-    case InstalledBinary                  = 'pie-installed-binary';
-    case PhpizeBinary                     = 'pie-phpize-binary';
-
-    /** @return PieMetadata */
-    public static function pieMetadataFromComposerPackage(CompletePackageInterface $composerPackage): array
-    {
-        $composerPackageExtras = $composerPackage->getExtra();
-
-        $onlyPieExtras = [];
-
-        foreach (array_column(self::cases(), 'value') as $pieMetadataKey) {
-            if (
-                ! array_key_exists($pieMetadataKey, $composerPackageExtras)
-                || ! is_string($composerPackageExtras[$pieMetadataKey])
-                || $composerPackageExtras[$pieMetadataKey] === ''
-            ) {
-                continue;
-            }
-
-            $onlyPieExtras[$pieMetadataKey] = $composerPackageExtras[$pieMetadataKey];
-        }
-
-        return $onlyPieExtras;
-    }
-}
diff --git a/src/ComposerIntegration/UninstallProcess.php b/src/ComposerIntegration/UninstallProcess.php
index cce50f73..80b10489 100644
--- a/src/ComposerIntegration/UninstallProcess.php
+++ b/src/ComposerIntegration/UninstallProcess.php
@@ -33,7 +33,15 @@ public function __invoke(
 
         $piePackage = Package::fromComposerCompletePackage($composerPackage);
 
-        $affectedIniFiles = ($this->removeIniEntry)($piePackage, $targetPlatform, $io);
+        $status = $piePackage->verifyPackageStatus($composerRequest->targetPlatform);
+
+        if ($status->isVerified()) {
+            $io->write(sprintf('👋 <info>Removed extension:</info> %s', ($this->uninstall)($targetPlatform, $piePackage)->filePath));
+        } else {
+            $io->writeError(sprintf('<warning>Did not remove extension file:</warning> %s', $status->description()));
+        }
+
+        $affectedIniFiles = ($this->removeIniEntry)($piePackage, $composerRequest->targetPlatform, $io);
 
         if (count($affectedIniFiles) === 1) {
             $io->write(
@@ -52,7 +60,5 @@ public function __invoke(
             );
             array_walk($affectedIniFiles, static fn (string $ini) => $io->write(' - ' . $ini));
         }
-
-        $io->write(sprintf('👋 <info>Removed extension:</info> %s', ($this->uninstall)($targetPlatform, $piePackage)->filePath));
     }
 }
diff --git a/src/DependencyResolver/Package.php b/src/DependencyResolver/Package.php
index 513b3ffb..6a33ca24 100644
--- a/src/DependencyResolver/Package.php
+++ b/src/DependencyResolver/Package.php
@@ -6,7 +6,7 @@
 
 use Composer\Package\CompletePackageInterface;
 use InvalidArgumentException;
-use Php\Pie\ComposerIntegration\PieInstalledJsonMetadataKeys;
+use Php\Pie\ComposerIntegration\InstalledJsonMetadata;
 use Php\Pie\ConfigureOption;
 use Php\Pie\Downloading\DownloadUrlMethod;
 use Php\Pie\ExtensionName;
@@ -56,6 +56,7 @@ final class Package
     private bool $supportNts                   = true;
     /** @var non-empty-list<DownloadUrlMethod>|null */
     private array|null $supportedDownloadUrlMethods = null;
+    private readonly InstalledJsonMetadata $installedJsonMetadata;
 
     public function __construct(
         private readonly CompletePackageInterface $composerPackage,
@@ -65,6 +66,7 @@ public function __construct(
         private readonly string $version,
         private readonly string|null $downloadUrl,
     ) {
+        $this->installedJsonMetadata = InstalledJsonMetadata::fromComposerPackage($this->composerPackage);
     }
 
     public static function fromComposerCompletePackage(CompletePackageInterface $completePackage): self
@@ -269,6 +271,11 @@ public function supportedDownloadUrlMethods(): array|null
         return $this->supportedDownloadUrlMethods;
     }
 
+    public function installedJsonMetadata(): InstalledJsonMetadata
+    {
+        return $this->installedJsonMetadata;
+    }
+
     public function verifyPackageStatus(TargetPlatform $targetPlatform): PackageVerificationStatus
     {
         $extensionPath    = $targetPlatform->phpBinaryPath->extensionPath();
@@ -282,9 +289,8 @@ public function verifyPackageStatus(TargetPlatform $targetPlatform): PackageVeri
             return PackageVerificationStatus::ActualBinaryNotFound;
         }
 
-        $installedJsonMetadata = PieInstalledJsonMetadataKeys::pieMetadataFromComposerPackage($this->composerPackage());
-        $pieExpectedBinaryPath = array_key_exists(PieInstalledJsonMetadataKeys::InstalledBinary->value, $installedJsonMetadata) ? $installedJsonMetadata[PieInstalledJsonMetadataKeys::InstalledBinary->value] : null;
-        $pieExpectedChecksum   = array_key_exists(PieInstalledJsonMetadataKeys::BinaryChecksum->value, $installedJsonMetadata) ? $installedJsonMetadata[PieInstalledJsonMetadataKeys::BinaryChecksum->value] : null;
+        $pieExpectedBinaryPath = $this->installedJsonMetadata()->installedBinary();
+        $pieExpectedChecksum   = $this->installedJsonMetadata()->binaryChecksum();
 
         if ($pieExpectedBinaryPath === null) {
             return PackageVerificationStatus::InstalledBinaryMetadataMissing;
diff --git a/src/Installing/PackageMetadataMissing.php b/src/Installing/PackageMetadataMissing.php
index 50c5ff7a..1509e3d1 100644
--- a/src/Installing/PackageMetadataMissing.php
+++ b/src/Installing/PackageMetadataMissing.php
@@ -4,6 +4,7 @@
 
 namespace Php\Pie\Installing;
 
+use Php\Pie\ComposerIntegration\InstalledJsonMetadata;
 use Php\Pie\DependencyResolver\Package;
 use RuntimeException;
 
@@ -15,13 +16,10 @@
 
 class PackageMetadataMissing extends RuntimeException
 {
-    /**
-     * @param array<string, mixed> $actualMetadata
-     * @param list<string>         $wantedKeys
-     */
-    public static function duringUninstall(Package $package, array $actualMetadata, array $wantedKeys): self
+    /** @param list<string> $wantedKeys */
+    public static function duringUninstall(Package $package, InstalledJsonMetadata $actualMetadata, array $wantedKeys): self
     {
-        $missingKeys = array_diff($wantedKeys, array_keys($actualMetadata));
+        $missingKeys = array_diff($wantedKeys, array_keys($actualMetadata->all()));
 
         return new self(sprintf(
             'PIE metadata was missing for package %s. Missing metadata key%s: %s',
diff --git a/src/Installing/UninstallUsingUnlink.php b/src/Installing/UninstallUsingUnlink.php
index 23b8abfd..80369d0e 100644
--- a/src/Installing/UninstallUsingUnlink.php
+++ b/src/Installing/UninstallUsingUnlink.php
@@ -5,7 +5,7 @@
 namespace Php\Pie\Installing;
 
 use Composer\Util\Platform as ComposerPlatform;
-use Php\Pie\ComposerIntegration\PieInstalledJsonMetadataKeys;
+use Php\Pie\ComposerIntegration\InstalledJsonMetadata;
 use Php\Pie\DependencyResolver\Package;
 use Php\Pie\File\BinaryFile;
 use Php\Pie\File\FailedToUnlinkFile;
@@ -16,7 +16,6 @@
 use Php\Pie\Util\Process;
 use RuntimeException;
 
-use function array_key_exists;
 use function file_exists;
 use function is_writable;
 use function sprintf;
@@ -28,18 +27,17 @@ class UninstallUsingUnlink implements Uninstall
 {
     public function __invoke(TargetPlatform $targetPlatform, Package $package): BinaryFile
     {
-        $pieMetadata = PieInstalledJsonMetadataKeys::pieMetadataFromComposerPackage($package->composerPackage());
+        $pieMetadata           = $package->installedJsonMetadata();
+        $pieExpectedBinaryPath = $pieMetadata->installedBinary();
+        $pieExpectedChecksum   = $pieMetadata->binaryChecksum();
 
-        if (
-            ! array_key_exists(PieInstalledJsonMetadataKeys::InstalledBinary->value, $pieMetadata)
-            || ! array_key_exists(PieInstalledJsonMetadataKeys::BinaryChecksum->value, $pieMetadata)
-        ) {
+        if ($pieExpectedBinaryPath === null || $pieExpectedChecksum === null) {
             throw PackageMetadataMissing::duringUninstall(
                 $package,
                 $pieMetadata,
                 [
-                    PieInstalledJsonMetadataKeys::InstalledBinary->value,
-                    PieInstalledJsonMetadataKeys::BinaryChecksum->value,
+                    InstalledJsonMetadata::KEY_INSTALLED_BINARY,
+                    InstalledJsonMetadata::KEY_BINARY_CHECKSUM,
                 ],
             );
         }
@@ -52,19 +50,15 @@ public function __invoke(TargetPlatform $targetPlatform, Package $package): Bina
             . ($targetPlatform->operatingSystem === OperatingSystem::Windows ? 'php_' : '')
             . $package->extensionName()->name()
             . ($targetPlatform->operatingSystem === OperatingSystem::Windows ? '.dll' : '.so');
-        if ($extensionPathByConvention !== $pieMetadata[PieInstalledJsonMetadataKeys::InstalledBinary->value]) {
+        if ($extensionPathByConvention !== $pieExpectedBinaryPath) {
             throw new RuntimeException(sprintf(
                 'Stored metadata path "%s" did not match expected path "%s"',
-                $pieMetadata[PieInstalledJsonMetadataKeys::InstalledBinary->value],
+                $pieExpectedBinaryPath,
                 $extensionPathByConvention,
             ));
         }
 
-        $expectedBinaryFile = new BinaryFile(
-            $pieMetadata[PieInstalledJsonMetadataKeys::InstalledBinary->value],
-            $pieMetadata[PieInstalledJsonMetadataKeys::BinaryChecksum->value],
-        );
-
+        $expectedBinaryFile = new BinaryFile($pieExpectedBinaryPath, $pieExpectedChecksum);
         $expectedBinaryFile->verify();
 
         // If the target directory isn't writable, or a .so file already exists and isn't writable, try to use sudo
diff --git a/src/Util/Emoji.php b/src/Util/Emoji.php
index 8e980019..7c160266 100644
--- a/src/Util/Emoji.php
+++ b/src/Util/Emoji.php
@@ -11,4 +11,5 @@ final class Emoji
     public const WARNING         = '⚠️ ';
     public const PROHIBITED      = '🚫';
     public const CROSS           = '❌';
+    public const INFO            = 'ℹ️ ';
 }
diff --git a/src/Util/PackageVerificationStatus.php b/src/Util/PackageVerificationStatus.php
index d0048194..272d8646 100644
--- a/src/Util/PackageVerificationStatus.php
+++ b/src/Util/PackageVerificationStatus.php
@@ -24,4 +24,9 @@ public function description(): string
             self::InstalledBinaryPathDoesNotMatchActualBinaryPath => Emoji::WARNING . ' - binary path mismatch',
         };
     }
+
+    public function isVerified(): bool
+    {
+        return $this === self::Verified;
+    }
 }
diff --git a/test/behaviour/CliContext.php b/test/behaviour/CliContext.php
index 2620c476..fb8b1b59 100644
--- a/test/behaviour/CliContext.php
+++ b/test/behaviour/CliContext.php
@@ -5,16 +5,18 @@
 namespace Php\PieBehaviourTest;
 
 use Behat\Behat\Context\Context;
+use Behat\Hook\AfterScenario;
 use Behat\Step\Given;
 use Behat\Step\Then;
 use Behat\Step\When;
 use Composer\Util\Platform;
+use Safe\Exceptions\PcreException;
 use Symfony\Component\Process\Process;
 use Webmozart\Assert\Assert;
 
 use function array_merge;
-use function assert;
 use function Safe\copy;
+use function Safe\preg_match_all;
 use function Safe\realpath;
 use function sprintf;
 use function str_contains;
@@ -28,12 +30,32 @@ class CliContext implements Context
     private string|null $errorOutput = null;
     private int|null $exitCode       = null;
     /** @var list<string> */
-    private array $phpArguments           = [];
-    private string $theExtension          = 'example_pie_extension';
+    private array $phpArguments  = [];
+    private string $theExtension = 'example_pie_extension';
+    /** @var non-empty-string */
     private string $thePackage            = 'asgrim/example-pie-extension';
     private string|null $workingDirectory = null;
 
+    /** @throws PcreException */
+    #[AfterScenario]
+    public function removeInstalledExtensions(): void
+    {
+        $this->runPieCommand(['show']);
+        if (! preg_match_all('#([a-zA-Z0-9-_]+/[a-zA-Z0-9-_]+):#', (string) $this->output, $installedExtensionPackageNames)) {
+            return;
+        }
+
+        foreach ($installedExtensionPackageNames[1] as $extensionPackageName) {
+            if ($extensionPackageName === 'xdebug/xdebug') {
+                continue;
+            }
+
+            $this->runPieCommand(['uninstall', $extensionPackageName]);
+        }
+    }
+
     #[When('I run a command to download the latest version of an extension')]
+    #[Given('an extension was previously downloaded but not built')]
     public function iRunACommandToDownloadTheLatestVersionOfAnExtension(): void
     {
         $this->runPieCommand(['download', 'asgrim/example-pie-extension']);
@@ -104,6 +126,7 @@ public function versionOfTheExtensionShouldHaveBeen(string $version): void
     }
 
     #[When('I run a command to build an extension')]
+    #[Given('an extension was previously built but not installed')]
     public function iRunACommandToBuildAnExtension(): void
     {
         $this->runPieCommand(['build', 'asgrim/example-pie-extension']);
@@ -170,6 +193,14 @@ public function iRunACommandToInstallAnExtension(): void
         $this->runPieCommand(['install', $this->thePackage]);
     }
 
+    #[When('I run a command to forcefully install an extension')]
+    public function iRunACommandToForcefullyInstallAnExtension(): void
+    {
+        $this->theExtension = 'example_pie_extension';
+        $this->thePackage   = 'asgrim/example-pie-extension';
+        $this->runPieCommand(['install', '--force', $this->thePackage]);
+    }
+
     #[When('I run a command to install an extension without enabling it')]
     public function iRunACommandToInstallAnExtensionWithoutEnabling(): void
     {
@@ -181,7 +212,6 @@ public function iRunACommandToInstallAnExtensionWithoutEnabling(): void
     #[When('I run a command to uninstall an extension')]
     public function iRunACommandToUninstallAnExtension(): void
     {
-        assert($this->thePackage !== '');
         $this->runPieCommand(['uninstall', $this->thePackage]);
     }
 
@@ -245,6 +275,20 @@ public function theExtensionShouldHaveBeenInstalledAndEnabled(): void
         Assert::same($isExtEnabled, 'yes');
     }
 
+    #[Then('the extension should not have been re-installed')]
+    public function theExtensionShouldNotHaveBeenReinstalled(): void
+    {
+        $this->assertCommandSuccessful();
+
+        Assert::contains($this->output, 'PIE package asgrim/example-pie-extension (example_pie_extension) is already installed and verified.');
+
+        $isExtEnabled = (new Process([self::PHP_BINARY, '-r', 'echo extension_loaded("' . $this->theExtension . '")?"yes":"no";']))
+            ->mustRun()
+            ->getOutput();
+
+        Assert::same($isExtEnabled, 'yes');
+    }
+
     #[Given('I have an invalid extension installed')]
     public function iHaveAnInvalidExtensionInstalled(): void
     {
diff --git a/test/integration/Command/BuildCommandTest.php b/test/integration/Command/BuildCommandTest.php
index 342e81ee..6db411a1 100644
--- a/test/integration/Command/BuildCommandTest.php
+++ b/test/integration/Command/BuildCommandTest.php
@@ -8,12 +8,11 @@
 use Php\Pie\Command\BuildCommand;
 use Php\Pie\Container;
 use PHPUnit\Framework\Attributes\CoversClass;
-use PHPUnit\Framework\TestCase;
 
 use function str_contains;
 
 #[CoversClass(BuildCommand::class)]
-class BuildCommandTest extends TestCase
+class BuildCommandTest extends IsolatedWorkingDirectoryTestCase
 {
     private const TEST_PACKAGE = 'asgrim/example-pie-extension';
 
@@ -21,6 +20,8 @@ class BuildCommandTest extends TestCase
 
     public function setUp(): void
     {
+        parent::setUp();
+
         $this->commandTester = new CommandTester(Container::testFactory()->get(BuildCommand::class));
     }
 
diff --git a/test/integration/Command/DownloadCommandTest.php b/test/integration/Command/DownloadCommandTest.php
index fb580fe8..7ce923c6 100644
--- a/test/integration/Command/DownloadCommandTest.php
+++ b/test/integration/Command/DownloadCommandTest.php
@@ -11,7 +11,6 @@
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\RequiresOperatingSystemFamily;
 use PHPUnit\Framework\Attributes\RequiresPhp;
-use PHPUnit\Framework\TestCase;
 
 use function array_combine;
 use function array_map;
@@ -21,7 +20,7 @@
 use const PHP_VERSION_ID;
 
 #[CoversClass(DownloadCommand::class)]
-class DownloadCommandTest extends TestCase
+class DownloadCommandTest extends IsolatedWorkingDirectoryTestCase
 {
     private const TEST_PACKAGE_LATEST = '2.0.9';
     private const TEST_PACKAGE        = 'asgrim/example-pie-extension';
@@ -30,6 +29,8 @@ class DownloadCommandTest extends TestCase
 
     public function setUp(): void
     {
+        parent::setUp();
+
         $this->commandTester = new CommandTester(Container::testFactory()->get(DownloadCommand::class));
     }
 
diff --git a/test/integration/Command/InfoCommandTest.php b/test/integration/Command/InfoCommandTest.php
index a0f520d8..5871f1f3 100644
--- a/test/integration/Command/InfoCommandTest.php
+++ b/test/integration/Command/InfoCommandTest.php
@@ -7,15 +7,16 @@
 use Php\Pie\Command\InfoCommand;
 use Php\Pie\Container;
 use PHPUnit\Framework\Attributes\CoversClass;
-use PHPUnit\Framework\TestCase;
 
 #[CoversClass(InfoCommand::class)]
-final class InfoCommandTest extends TestCase
+final class InfoCommandTest extends IsolatedWorkingDirectoryTestCase
 {
     private CommandTester $commandTester;
 
     public function setUp(): void
     {
+        parent::setUp();
+
         $this->commandTester = new CommandTester(Container::testFactory()->get(InfoCommand::class));
     }
 
diff --git a/test/integration/Command/InstallCommandTest.php b/test/integration/Command/InstallCommandTest.php
index 9ba63c84..631325bc 100644
--- a/test/integration/Command/InstallCommandTest.php
+++ b/test/integration/Command/InstallCommandTest.php
@@ -10,7 +10,6 @@
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\RequiresOperatingSystemFamily;
-use PHPUnit\Framework\TestCase;
 use Symfony\Component\Console\Output\BufferedOutput;
 use Symfony\Component\Process\Process;
 
@@ -19,26 +18,40 @@
 use function array_key_exists;
 use function array_map;
 use function array_unshift;
-use function assert;
 use function file_exists;
 use function is_executable;
-use function is_file;
-use function is_string;
 use function is_writable;
 use function Safe\preg_match;
 
 #[CoversClass(InstallCommand::class)]
-class InstallCommandTest extends TestCase
+class InstallCommandTest extends IsolatedWorkingDirectoryTestCase
 {
     private const TEST_PACKAGE = 'asgrim/example-pie-extension';
 
     private CommandTester $commandTester;
+    private string|null $lastInstalledBinary = null;
 
     public function setUp(): void
     {
+        parent::setUp();
+
         $this->commandTester = new CommandTester(Container::testFactory()->get(InstallCommand::class));
     }
 
+    protected function tearDown(): void
+    {
+        if ($this->lastInstalledBinary !== null && file_exists($this->lastInstalledBinary)) {
+            $rmCommand = ['rm', $this->lastInstalledBinary];
+            if (! is_writable($this->lastInstalledBinary)) {
+                array_unshift($rmCommand, 'sudo');
+            }
+
+            (new Process($rmCommand))->run();
+        }
+
+        parent::tearDown();
+    }
+
     /** @return array<string, array{0: string}> */
     public static function phpPathProvider(): array
     {
@@ -87,27 +100,17 @@ public function testInstallCommandWillInstallCompatibleExtensionNonWindows(strin
         $this->commandTester->assertCommandIsSuccessful();
 
         $outputString = $this->commandTester->getDisplay();
-        self::assertStringContainsString('Install complete: ', $outputString);
-        self::assertStringContainsString('You must now add "extension=example_pie_extension" to your php.ini', $outputString);
 
         if (
-            ! preg_match('#^Install complete: (.*)$#m', $outputString, $matches)
-            || ! array_key_exists(1, $matches)
-            || $matches[1] === ''
-            || ! file_exists($matches[1])
-            || ! is_file($matches[1])
+            preg_match('#^Install complete: (.*)$#m', $outputString, $matches)
+            && array_key_exists(1, $matches)
+            && $matches[1] !== ''
         ) {
-            return;
+            $this->lastInstalledBinary = $matches[1];
         }
 
-        $fileToRemove = $matches[1];
-        assert(is_string($fileToRemove));
-        $rmCommand = ['rm', $fileToRemove];
-        if (! is_writable($fileToRemove)) {
-            array_unshift($rmCommand, 'sudo');
-        }
-
-        (new Process($rmCommand))->mustRun();
+        self::assertStringContainsString('Install complete: ', $outputString);
+        self::assertStringContainsString('You must now add "extension=example_pie_extension" to your php.ini', $outputString);
     }
 
     #[RequiresOperatingSystemFamily('Windows')]
@@ -121,19 +124,16 @@ public function testInstallCommandWillInstallCompatibleExtensionWindows(): void
         $this->commandTester->assertCommandIsSuccessful();
 
         $outputString = $this->commandTester->getDisplay();
-        self::assertStringContainsString('Copied DLL to: ', $outputString);
-        self::assertStringContainsString('You must now add "extension=example_pie_extension" to your php.ini', $outputString);
 
         if (
-            ! preg_match('#^Copied DLL to: (.*)$#m', $outputString, $matches)
-            || ! array_key_exists(1, $matches)
-            || $matches[1] === ''
-            || ! file_exists($matches[1])
-            || ! is_file($matches[1])
+            preg_match('#^Copied DLL to: (.*)$#m', $outputString, $matches)
+            && array_key_exists(1, $matches)
+            && $matches[1] !== ''
         ) {
-            return;
+            $this->lastInstalledBinary = $matches[1];
         }
 
-        (new Process(['rm', $matches[1]]))->mustRun();
+        self::assertStringContainsString('Copied DLL to: ', $outputString);
+        self::assertStringContainsString('You must now add "extension=example_pie_extension" to your php.ini', $outputString);
     }
 }
diff --git a/test/integration/Command/IsolatedWorkingDirectoryTestCase.php b/test/integration/Command/IsolatedWorkingDirectoryTestCase.php
new file mode 100644
index 00000000..e3d7dec8
--- /dev/null
+++ b/test/integration/Command/IsolatedWorkingDirectoryTestCase.php
@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Php\PieIntegrationTest\Command;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Process\Process;
+
+use function file_exists;
+use function Safe\putenv;
+use function sys_get_temp_dir;
+use function uniqid;
+
+class IsolatedWorkingDirectoryTestCase extends TestCase
+{
+    private string $tempPieDir;
+
+    public function setUp(): void
+    {
+        $this->tempPieDir = sys_get_temp_dir() . '/pie-test-' . uniqid();
+        putenv('PIE_WORKING_DIRECTORY=' . $this->tempPieDir);
+    }
+
+    protected function tearDown(): void
+    {
+        if (file_exists($this->tempPieDir)) {
+            (new Process(['rm', '-rf', $this->tempPieDir]))->run();
+        }
+
+        putenv('PIE_WORKING_DIRECTORY');
+    }
+}
diff --git a/test/integration/Command/RepositoryManagementCommandsTest.php b/test/integration/Command/RepositoryManagementCommandsTest.php
index b93c411e..3e31148b 100644
--- a/test/integration/Command/RepositoryManagementCommandsTest.php
+++ b/test/integration/Command/RepositoryManagementCommandsTest.php
@@ -9,7 +9,6 @@
 use Php\Pie\Command\RepositoryRemoveCommand;
 use Php\Pie\Container;
 use PHPUnit\Framework\Attributes\CoversClass;
-use PHPUnit\Framework\TestCase;
 
 use function array_filter;
 use function array_map;
@@ -23,7 +22,7 @@
 #[CoversClass(RepositoryListCommand::class)]
 #[CoversClass(RepositoryAddCommand::class)]
 #[CoversClass(RepositoryRemoveCommand::class)]
-final class RepositoryManagementCommandsTest extends TestCase
+final class RepositoryManagementCommandsTest extends IsolatedWorkingDirectoryTestCase
 {
     private const EXAMPLE_PATH_REPOSITORY_URL = __DIR__;
     private const EXAMPLE_VCS_REPOSITORY_URL  = 'https://github.com/asgrim/example-pie-extension';
@@ -35,6 +34,8 @@ final class RepositoryManagementCommandsTest extends TestCase
 
     public function setUp(): void
     {
+        parent::setUp();
+
         $this->listCommand   = new CommandTester(Container::testFactory()->get(RepositoryListCommand::class));
         $this->addCommand    = new CommandTester(Container::testFactory()->get(RepositoryAddCommand::class));
         $this->removeCommand = new CommandTester(Container::testFactory()->get(RepositoryRemoveCommand::class));
diff --git a/test/unit/ComposerIntegration/InstalledJsonMetadataTest.php b/test/unit/ComposerIntegration/AddInstalledJsonMetadataTest.php
similarity index 93%
rename from test/unit/ComposerIntegration/InstalledJsonMetadataTest.php
rename to test/unit/ComposerIntegration/AddInstalledJsonMetadataTest.php
index 20234dff..111f2324 100644
--- a/test/unit/ComposerIntegration/InstalledJsonMetadataTest.php
+++ b/test/unit/ComposerIntegration/AddInstalledJsonMetadataTest.php
@@ -10,7 +10,7 @@
 use Composer\Package\CompletePackageInterface;
 use Composer\Repository\InstalledArrayRepository;
 use Composer\Repository\RepositoryManager;
-use Php\Pie\ComposerIntegration\InstalledJsonMetadata;
+use Php\Pie\ComposerIntegration\AddInstalledJsonMetadata;
 use Php\Pie\ComposerIntegration\PieComposerRequest;
 use Php\Pie\ComposerIntegration\PieOperation;
 use Php\Pie\DependencyResolver\RequestedPackageAndVersion;
@@ -26,8 +26,8 @@
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
 
-#[CoversClass(InstalledJsonMetadata::class)]
-final class InstalledJsonMetadataTest extends TestCase
+#[CoversClass(AddInstalledJsonMetadata::class)]
+final class AddInstalledJsonMetadataTest extends TestCase
 {
     private function mockComposerInstalledRepositoryWith(CompletePackageInterface $package): Composer&MockObject
     {
@@ -48,7 +48,7 @@ public function testMetadataForDownloads(): void
 
         $phpBinary = PhpBinaryPath::fromCurrentProcess();
 
-        (new InstalledJsonMetadata())->addDownloadMetadata(
+        (new AddInstalledJsonMetadata())->addDownloadMetadata(
             $this->mockComposerInstalledRepositoryWith($package),
             new PieComposerRequest(
                 $this->createMock(IOInterface::class),
@@ -87,7 +87,7 @@ public function testMetadataForBuilds(): void
     {
         $package = new CompletePackage('foo/bar', '1.2.3.0', '1.2.3');
 
-        (new InstalledJsonMetadata())->addBuildMetadata(
+        (new AddInstalledJsonMetadata())->addBuildMetadata(
             $this->mockComposerInstalledRepositoryWith($package),
             new PieComposerRequest(
                 $this->createMock(IOInterface::class),
@@ -125,7 +125,7 @@ public function testMetadataForInstalls(): void
     {
         $package = new CompletePackage('foo/bar', '1.2.3.0', '1.2.3');
 
-        (new InstalledJsonMetadata())->addInstallMetadata(
+        (new AddInstalledJsonMetadata())->addInstallMetadata(
             $this->mockComposerInstalledRepositoryWith($package),
             clone $package,
             new BinaryFile('/path/to/installed', 'ignore'),
diff --git a/test/unit/ComposerIntegration/InstallAndBuildProcessTest.php b/test/unit/ComposerIntegration/InstallAndBuildProcessTest.php
index 6318ba6e..be713a05 100644
--- a/test/unit/ComposerIntegration/InstallAndBuildProcessTest.php
+++ b/test/unit/ComposerIntegration/InstallAndBuildProcessTest.php
@@ -9,8 +9,8 @@
 use Composer\PartialComposer;
 use Php\Pie\Building\Build;
 use Php\Pie\Building\PlaceholderReplacer;
+use Php\Pie\ComposerIntegration\AddInstalledJsonMetadata;
 use Php\Pie\ComposerIntegration\InstallAndBuildProcess;
-use Php\Pie\ComposerIntegration\InstalledJsonMetadata;
 use Php\Pie\ComposerIntegration\PieComposerRequest;
 use Php\Pie\ComposerIntegration\PieOperation;
 use Php\Pie\DependencyResolver\RequestedPackageAndVersion;
@@ -31,7 +31,7 @@ final class InstallAndBuildProcessTest extends TestCase
 {
     private Build&MockObject $pieBuild;
     private Install&MockObject $pieInstall;
-    private InstalledJsonMetadata&MockObject $installedJsonMetadata;
+    private AddInstalledJsonMetadata&MockObject $addInstalledJsonMetadata;
 
     private InstallAndBuildProcess $installAndBuildProcess;
 
@@ -39,14 +39,14 @@ public function setUp(): void
     {
         parent::setUp();
 
-        $this->pieBuild              = $this->createMock(Build::class);
-        $this->pieInstall            = $this->createMock(Install::class);
-        $this->installedJsonMetadata = $this->createMock(InstalledJsonMetadata::class);
+        $this->pieBuild                 = $this->createMock(Build::class);
+        $this->pieInstall               = $this->createMock(Install::class);
+        $this->addInstalledJsonMetadata = $this->createMock(AddInstalledJsonMetadata::class);
 
         $this->installAndBuildProcess = new InstallAndBuildProcess(
             $this->pieBuild,
             $this->pieInstall,
-            $this->installedJsonMetadata,
+            $this->addInstalledJsonMetadata,
             $this->createMock(PlaceholderReplacer::class),
         );
     }
@@ -74,11 +74,11 @@ public function testDownloadWithoutBuildAndInstall(): void
         $composerPackage = new CompletePackage('foo/bar', '1.2.3.0', '1.2.3');
         $installPath     = '/path/to/install';
 
-        $this->installedJsonMetadata->expects(self::once())->method('addDownloadMetadata');
+        $this->addInstalledJsonMetadata->expects(self::once())->method('addDownloadMetadata');
 
-        $this->installedJsonMetadata->expects(self::never())->method('addBuildMetadata');
+        $this->addInstalledJsonMetadata->expects(self::never())->method('addBuildMetadata');
 
-        $this->installedJsonMetadata->expects(self::never())->method('addInstallMetadata');
+        $this->addInstalledJsonMetadata->expects(self::never())->method('addInstallMetadata');
 
         $this->pieBuild->expects(self::never())->method('__invoke');
 
@@ -115,11 +115,11 @@ public function testDownloadAndBuildWithoutInstall(): void
         $composerPackage = new CompletePackage('foo/bar', '1.2.3.0', '1.2.3');
         $installPath     = '/path/to/install';
 
-        $this->installedJsonMetadata->expects(self::once())->method('addDownloadMetadata');
+        $this->addInstalledJsonMetadata->expects(self::once())->method('addDownloadMetadata');
 
-        $this->installedJsonMetadata->expects(self::once())->method('addBuildMetadata');
+        $this->addInstalledJsonMetadata->expects(self::once())->method('addBuildMetadata');
 
-        $this->installedJsonMetadata->expects(self::never())->method('addInstallMetadata');
+        $this->addInstalledJsonMetadata->expects(self::never())->method('addInstallMetadata');
 
         $this->pieBuild
             ->expects(self::once())
@@ -159,11 +159,11 @@ public function testDownloadBuildAndInstall(): void
         $composerPackage = new CompletePackage('foo/bar', '1.2.3.0', '1.2.3');
         $installPath     = '/path/to/install';
 
-        $this->installedJsonMetadata->expects(self::once())->method('addDownloadMetadata');
+        $this->addInstalledJsonMetadata->expects(self::once())->method('addDownloadMetadata');
 
-        $this->installedJsonMetadata->expects(self::once())->method('addBuildMetadata');
+        $this->addInstalledJsonMetadata->expects(self::once())->method('addBuildMetadata');
 
-        $this->installedJsonMetadata->expects(self::once())->method('addInstallMetadata');
+        $this->addInstalledJsonMetadata->expects(self::once())->method('addInstallMetadata');
 
         $this->pieBuild
             ->expects(self::once())
diff --git a/test/unit/ComposerIntegration/PieInstalledJsonMetadataKeysTest.php b/test/unit/ComposerIntegration/PieInstalledJsonMetadataKeysTest.php
deleted file mode 100644
index e689d09e..00000000
--- a/test/unit/ComposerIntegration/PieInstalledJsonMetadataKeysTest.php
+++ /dev/null
@@ -1,44 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Php\PieUnitTest\ComposerIntegration;
-
-use Composer\Package\CompletePackageInterface;
-use Php\Pie\ComposerIntegration\PieInstalledJsonMetadataKeys;
-use PHPUnit\Framework\Attributes\CoversClass;
-use PHPUnit\Framework\TestCase;
-
-#[CoversClass(PieInstalledJsonMetadataKeys::class)]
-final class PieInstalledJsonMetadataKeysTest extends TestCase
-{
-    public function testPieMetadataFromComposerPackageWithEmptyExtra(): void
-    {
-        $composerPackage = $this->createMock(CompletePackageInterface::class);
-        $composerPackage->expects(self::once())
-            ->method('getExtra')
-            ->willReturn([]);
-
-        self::assertSame([], PieInstalledJsonMetadataKeys::pieMetadataFromComposerPackage($composerPackage));
-    }
-
-    public function testPieMetadataFromComposerPackageWithPopulatedExtra(): void
-    {
-        $composerPackage = $this->createMock(CompletePackageInterface::class);
-        $composerPackage->expects(self::once())
-            ->method('getExtra')
-            ->willReturn([
-                PieInstalledJsonMetadataKeys::InstalledBinary->value => '/path/to/some/file',
-                PieInstalledJsonMetadataKeys::BinaryChecksum->value => 'some-checksum-value',
-                'something else' => 'hopefully this does not make it in',
-            ]);
-
-        self::assertEqualsCanonicalizing(
-            [
-                PieInstalledJsonMetadataKeys::InstalledBinary->value => '/path/to/some/file',
-                PieInstalledJsonMetadataKeys::BinaryChecksum->value => 'some-checksum-value',
-            ],
-            PieInstalledJsonMetadataKeys::pieMetadataFromComposerPackage($composerPackage),
-        );
-    }
-}
diff --git a/test/unit/Installing/PackageMetadataMissingTest.php b/test/unit/Installing/PackageMetadataMissingTest.php
index 5fdc5a78..bb282980 100644
--- a/test/unit/Installing/PackageMetadataMissingTest.php
+++ b/test/unit/Installing/PackageMetadataMissingTest.php
@@ -5,6 +5,7 @@
 namespace Php\PieUnitTest\Installing;
 
 use Composer\Package\CompletePackageInterface;
+use Php\Pie\ComposerIntegration\InstalledJsonMetadata;
 use Php\Pie\DependencyResolver\Package;
 use Php\Pie\ExtensionName;
 use Php\Pie\ExtensionType;
@@ -28,10 +29,10 @@ public function testDuringUninstall(): void
 
         $exception = PackageMetadataMissing::duringUninstall(
             $package,
-            [
+            InstalledJsonMetadata::fromArray([
                 'a' => 'something',
                 'b' => 'something else',
-            ],
+            ]),
             ['b', 'c', 'd'],
         );
 
diff --git a/test/unit/Installing/UninstallUsingUnlinkTest.php b/test/unit/Installing/UninstallUsingUnlinkTest.php
index 66d4c8cb..f81ebd3e 100644
--- a/test/unit/Installing/UninstallUsingUnlinkTest.php
+++ b/test/unit/Installing/UninstallUsingUnlinkTest.php
@@ -6,7 +6,7 @@
 
 use Composer\Package\CompletePackageInterface;
 use Composer\Util\Filesystem;
-use Php\Pie\ComposerIntegration\PieInstalledJsonMetadataKeys;
+use Php\Pie\ComposerIntegration\InstalledJsonMetadata;
 use Php\Pie\DependencyResolver\Package;
 use Php\Pie\ExtensionName;
 use Php\Pie\ExtensionType;
@@ -100,8 +100,8 @@ public function testBinaryFileIsRemoved(): void
         $composerPackage
             ->method('getExtra')
             ->willReturn([
-                PieInstalledJsonMetadataKeys::InstalledBinary->value => $extensionFile,
-                PieInstalledJsonMetadataKeys::BinaryChecksum->value => $testHash,
+                InstalledJsonMetadata::KEY_INSTALLED_BINARY => $extensionFile,
+                InstalledJsonMetadata::KEY_BINARY_CHECKSUM => $testHash,
             ]);
 
         $package = new Package(
@@ -148,8 +148,8 @@ public function testBinaryFileIsRemovedOnWindows(): void
         $composerPackage
             ->method('getExtra')
             ->willReturn([
-                PieInstalledJsonMetadataKeys::InstalledBinary->value => $extensionFile,
-                PieInstalledJsonMetadataKeys::BinaryChecksum->value => $testHash,
+                InstalledJsonMetadata::KEY_INSTALLED_BINARY => $extensionFile,
+                InstalledJsonMetadata::KEY_BINARY_CHECKSUM => $testHash,
             ]);
 
         $package = new Package(
@@ -200,8 +200,8 @@ public function testBinaryFileIsRemovedWhenInstallRootUsed(): void
         $composerPackage
             ->method('getExtra')
             ->willReturn([
-                PieInstalledJsonMetadataKeys::InstalledBinary->value => $extensionFile,
-                PieInstalledJsonMetadataKeys::BinaryChecksum->value => $testHash,
+                InstalledJsonMetadata::KEY_INSTALLED_BINARY => $extensionFile,
+                InstalledJsonMetadata::KEY_BINARY_CHECKSUM => $testHash,
             ]);
 
         $package = new Package(
@@ -251,8 +251,8 @@ public function testExtensionPathInMetadataNotMatchingConventionWillThrowExcepti
         $composerPackage
             ->method('getExtra')
             ->willReturn([
-                PieInstalledJsonMetadataKeys::InstalledBinary->value => $extensionFile,
-                PieInstalledJsonMetadataKeys::BinaryChecksum->value => $testHash,
+                InstalledJsonMetadata::KEY_INSTALLED_BINARY => $extensionFile,
+                InstalledJsonMetadata::KEY_BINARY_CHECKSUM => $testHash,
             ]);
 
         $package = new Package(