diff --git a/composer.json b/composer.json
index ea6d26328971..c109bbd5be55 100644
--- a/composer.json
+++ b/composer.json
@@ -123,7 +123,6 @@
             "Rector\\NodeNestingScope\\": "packages/node-nesting-scope/src",
             "Rector\\Sensio\\": "rules/sensio/src",
             "Rector\\Shopware\\": "rules/shopware/src",
-            "Rector\\Silverstripe\\": "rules/silverstripe/src",
             "Rector\\StaticTypeMapper\\": "packages/static-type-mapper/src",
             "Rector\\StrictCodeQuality\\": "rules/strict-code-quality/src",
             "Rector\\Sylius\\": "rules/sylius/src",
@@ -194,7 +193,6 @@
             "Rector\\SOLID\\Tests\\": "rules/solid/tests",
             "Rector\\Sensio\\Tests\\": "rules/sensio/tests",
             "Rector\\Shopware\\Tests\\": "rules/shopware/tests",
-            "Rector\\Silverstripe\\Tests\\": "rules/silverstripe/tests",
             "Rector\\StrictCodeQuality\\Tests\\": "rules/strict-code-quality/tests",
             "Rector\\Sylius\\Tests\\": "rules/sylius/tests",
             "Rector\\SymfonyCodeQuality\\Tests\\": "rules/symfony-code-quality/tests",
diff --git a/config/set/silverstripe/silverstripe.yaml b/config/set/silverstripe/silverstripe.yaml
deleted file mode 100644
index dfe16729967f..000000000000
--- a/config/set/silverstripe/silverstripe.yaml
+++ /dev/null
@@ -1,5 +0,0 @@
-# various versions
-services:
-    # https://github.com/silverstripe/silverstripe-upgrader/issues/76
-    Rector\Silverstripe\Rector\ConstantToStaticCallRector: null
-    Rector\Silverstripe\Rector\DefineConstantToStaticCallRector: null
diff --git a/docs/how_it_works.md b/docs/how_it_works.md
index 82caf8cc9e99..c3f3b4e71870 100644
--- a/docs/how_it_works.md
+++ b/docs/how_it_works.md
@@ -87,6 +87,7 @@ services:
 ### Similar Projects
 
 - [ClangMR](https://static.googleusercontent.com/media/research.google.com/en//pubs/archive/41342.pdf) for C++ by Google (closed source) - almost idential workflow, developed independently though
+- [hhast](https://github.com/hhvm/hhast) - HHVM AST + format preserving + mirations
 - [facebook/jscodeshift](https://github.com/facebook/jscodeshift) for Javascript
 - [silverstripe/silverstripe-upgrader](https://github.com/silverstripe/silverstripe-upgrader) for PHP CMS, Silverstripe
 - [dereuromark/upgrade](https://github.com/dereuromark/upgrade) for PHP Framework, CakePHP
diff --git a/docs/rector_rules_overview.md b/docs/rector_rules_overview.md
index 7a168a9961ee..0e8334822811 100644
--- a/docs/rector_rules_overview.md
+++ b/docs/rector_rules_overview.md
@@ -1,4 +1,4 @@
-# All 490 Rectors Overview
+# All 488 Rectors Overview
 
 - [Projects](#projects)
 - [General](#general)
@@ -59,7 +59,6 @@
 - [SOLID](#solid) (11)
 - [Sensio](#sensio) (1)
 - [Shopware](#shopware) (3)
-- [Silverstripe](#silverstripe) (2)
 - [StrictCodeQuality](#strictcodequality) (1)
 - [Sylius](#sylius) (1)
 - [Symfony](#symfony) (29)
@@ -4147,7 +4146,7 @@ Change singleton class to normal class that can be registered as a service
 
 ### `FunctionToStaticMethodRector`
 
-- class: [`Rector\Legacy\Rector\Node\FunctionToStaticMethodRector`](/../master/rules/legacy/src/Rector/Node/FunctionToStaticMethodRector.php)
+- class: [`Rector\Legacy\Rector\FileSystem\FunctionToStaticMethodRector`](/../master/rules/legacy/src/Rector/FileSystem/FunctionToStaticMethodRector.php)
 
 Change functions to static calls, so composer can autoload them
 
@@ -9282,36 +9281,6 @@ Use version from di parameter
 
 <br>
 
-## Silverstripe
-
-### `ConstantToStaticCallRector`
-
-- class: [`Rector\Silverstripe\Rector\ConstantToStaticCallRector`](/../master/rules/silverstripe/src/Rector/ConstantToStaticCallRector.php)
-- [test fixtures](/../master/rules/silverstripe/tests/Rector/ConstantToStaticCallRector/Fixture)
-
-Turns defined constant to static method call.
-
-```diff
--SS_DATABASE_NAME;
-+Environment::getEnv("SS_DATABASE_NAME");
-```
-
-<br>
-
-### `DefineConstantToStaticCallRector`
-
-- class: [`Rector\Silverstripe\Rector\DefineConstantToStaticCallRector`](/../master/rules/silverstripe/src/Rector/DefineConstantToStaticCallRector.php)
-- [test fixtures](/../master/rules/silverstripe/tests/Rector/DefineConstantToStaticCallRector/Fixture)
-
-Turns defined function call to static method call.
-
-```diff
--defined("SS_DATABASE_NAME");
-+Environment::getEnv("SS_DATABASE_NAME");
-```
-
-<br>
-
 ## StrictCodeQuality
 
 ### `VarInlineAnnotationToAssertRector`
diff --git a/rules/silverstripe/src/Rector/ConstantToStaticCallRector.php b/rules/silverstripe/src/Rector/ConstantToStaticCallRector.php
deleted file mode 100644
index 36680c7cf4bf..000000000000
--- a/rules/silverstripe/src/Rector/ConstantToStaticCallRector.php
+++ /dev/null
@@ -1,51 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Rector\Silverstripe\Rector;
-
-use Nette\Utils\Strings;
-use PhpParser\Node;
-use PhpParser\Node\Expr\ConstFetch;
-use PhpParser\Node\Scalar\String_;
-use Rector\Core\Rector\AbstractRector;
-use Rector\Core\RectorDefinition\CodeSample;
-use Rector\Core\RectorDefinition\RectorDefinition;
-
-/**
- * @see \Rector\Silverstripe\Tests\Rector\ConstantToStaticCallRector\ConstantToStaticCallRectorTest
- */
-final class ConstantToStaticCallRector extends AbstractRector
-{
-    public function getDefinition(): RectorDefinition
-    {
-        return new RectorDefinition('Turns defined constant to static method call.', [
-            new CodeSample('SS_DATABASE_NAME;', 'Environment::getEnv("SS_DATABASE_NAME");'),
-        ]);
-    }
-
-    /**
-     * @return string[]
-     */
-    public function getNodeTypes(): array
-    {
-        return [ConstFetch::class];
-    }
-
-    /**
-     * @param ConstFetch $node
-     */
-    public function refactor(Node $node): ?Node
-    {
-        $constantName = $this->getName($node);
-        if ($constantName === null) {
-            return null;
-        }
-
-        if (! Strings::startsWith($constantName, 'SS_')) {
-            return null;
-        }
-
-        return $this->createStaticCall('Environment', 'getEnv', [new String_($constantName)]);
-    }
-}
diff --git a/rules/silverstripe/src/Rector/DefineConstantToStaticCallRector.php b/rules/silverstripe/src/Rector/DefineConstantToStaticCallRector.php
deleted file mode 100644
index c8a248905f56..000000000000
--- a/rules/silverstripe/src/Rector/DefineConstantToStaticCallRector.php
+++ /dev/null
@@ -1,59 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Rector\Silverstripe\Rector;
-
-use Nette\Utils\Strings;
-use PhpParser\Node;
-use PhpParser\Node\Expr\FuncCall;
-use PhpParser\Node\Scalar\String_;
-use Rector\Core\Rector\AbstractRector;
-use Rector\Core\RectorDefinition\CodeSample;
-use Rector\Core\RectorDefinition\RectorDefinition;
-
-/**
- * @see \Rector\Silverstripe\Tests\Rector\DefineConstantToStaticCallRector\DefineConstantToStaticCallRectorTest
- */
-final class DefineConstantToStaticCallRector extends AbstractRector
-{
-    public function getDefinition(): RectorDefinition
-    {
-        return new RectorDefinition('Turns defined function call to static method call.', [
-            new CodeSample('defined("SS_DATABASE_NAME");', 'Environment::getEnv("SS_DATABASE_NAME");'),
-        ]);
-    }
-
-    /**
-     * @return string[]
-     */
-    public function getNodeTypes(): array
-    {
-        return [FuncCall::class];
-    }
-
-    /**
-     * @param FuncCall $node
-     */
-    public function refactor(Node $node): ?Node
-    {
-        if (count($node->args) !== 1) {
-            return null;
-        }
-
-        if (! $this->isName($node, 'defined')) {
-            return null;
-        }
-
-        $argumentValue = $node->args[0]->value;
-        if (! $argumentValue instanceof String_) {
-            return null;
-        }
-
-        if (! Strings::startsWith($argumentValue->value, 'SS_')) {
-            return null;
-        }
-
-        return $this->createStaticCall('Environment', 'getEnv', $node->args);
-    }
-}
diff --git a/rules/silverstripe/tests/Rector/ConstantToStaticCallRector/ConstantToStaticCallRectorTest.php b/rules/silverstripe/tests/Rector/ConstantToStaticCallRector/ConstantToStaticCallRectorTest.php
deleted file mode 100644
index fd115d460326..000000000000
--- a/rules/silverstripe/tests/Rector/ConstantToStaticCallRector/ConstantToStaticCallRectorTest.php
+++ /dev/null
@@ -1,30 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Rector\Silverstripe\Tests\Rector\ConstantToStaticCallRector;
-
-use Iterator;
-use Rector\Core\Testing\PHPUnit\AbstractRectorTestCase;
-use Rector\Silverstripe\Rector\ConstantToStaticCallRector;
-
-final class ConstantToStaticCallRectorTest extends AbstractRectorTestCase
-{
-    /**
-     * @dataProvider provideData()
-     */
-    public function test(string $file): void
-    {
-        $this->doTestFile($file);
-    }
-
-    public function provideData(): Iterator
-    {
-        return $this->yieldFilesFromDirectory(__DIR__ . '/Fixture');
-    }
-
-    protected function getRectorClass(): string
-    {
-        return ConstantToStaticCallRector::class;
-    }
-}
diff --git a/rules/silverstripe/tests/Rector/ConstantToStaticCallRector/Fixture/fixture.php.inc b/rules/silverstripe/tests/Rector/ConstantToStaticCallRector/Fixture/fixture.php.inc
deleted file mode 100644
index 0de6ba3b43a8..000000000000
--- a/rules/silverstripe/tests/Rector/ConstantToStaticCallRector/Fixture/fixture.php.inc
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-function constantToStaticCall()
-{
-    if (defined('SS_DATABASE_NAME')) {
-        echo SS_DATABASENAME;
-    }
-}
-
-?>
------
-<?php
-
-function constantToStaticCall()
-{
-    if (defined('SS_DATABASE_NAME')) {
-        echo \Environment::getEnv('SS_DATABASENAME');
-    }
-}
-
-?>
diff --git a/rules/silverstripe/tests/Rector/DefineConstantToStaticCallRector/DefineConstantToStaticCallRectorTest.php b/rules/silverstripe/tests/Rector/DefineConstantToStaticCallRector/DefineConstantToStaticCallRectorTest.php
deleted file mode 100644
index 1f05b042c26c..000000000000
--- a/rules/silverstripe/tests/Rector/DefineConstantToStaticCallRector/DefineConstantToStaticCallRectorTest.php
+++ /dev/null
@@ -1,30 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Rector\Silverstripe\Tests\Rector\DefineConstantToStaticCallRector;
-
-use Iterator;
-use Rector\Core\Testing\PHPUnit\AbstractRectorTestCase;
-use Rector\Silverstripe\Rector\DefineConstantToStaticCallRector;
-
-final class DefineConstantToStaticCallRectorTest extends AbstractRectorTestCase
-{
-    /**
-     * @dataProvider provideData()
-     */
-    public function test(string $file): void
-    {
-        $this->doTestFile($file);
-    }
-
-    public function provideData(): Iterator
-    {
-        return $this->yieldFilesFromDirectory(__DIR__ . '/Fixture');
-    }
-
-    protected function getRectorClass(): string
-    {
-        return DefineConstantToStaticCallRector::class;
-    }
-}
diff --git a/rules/silverstripe/tests/Rector/DefineConstantToStaticCallRector/Fixture/fixture.php.inc b/rules/silverstripe/tests/Rector/DefineConstantToStaticCallRector/Fixture/fixture.php.inc
deleted file mode 100644
index 091dae8b3d83..000000000000
--- a/rules/silverstripe/tests/Rector/DefineConstantToStaticCallRector/Fixture/fixture.php.inc
+++ /dev/null
@@ -1,25 +0,0 @@
-<?php
-
-namespace Rector\Silverstripe\Tests\Rector\DefineConstantToStaticCallRector\Fixture;
-
-function defineConstantToStaticCall()
-{
-    if (defined('SS_DATABASE_NAME')) {
-        echo SS_DATABASENAME;
-    }
-}
-
-?>
------
-<?php
-
-namespace Rector\Silverstripe\Tests\Rector\DefineConstantToStaticCallRector\Fixture;
-
-function defineConstantToStaticCall()
-{
-    if (\Environment::getEnv('SS_DATABASE_NAME')) {
-        echo SS_DATABASENAME;
-    }
-}
-
-?>
diff --git a/sonar-project.properties b/sonar-project.properties
index 97f2c4162a21..a87e4f733ac7 100644
--- a/sonar-project.properties
+++ b/sonar-project.properties
@@ -4,9 +4,9 @@ sonar.projectKey=rectorphp_rector
 
 # relative paths to source
 # wildcards don't work :(
-sonar.sources=compiler/src,src,rules/autodiscovery/src,rules/architecture/src,packages/attribute-aware-php-doc/src,packages/better-php-doc-parser/src,rules/cakephp/src,rules/celebrity/src,rules/code-quality/src,rules/coding-style/src,packages/console-differ/src,rules/dead-code/src,rules/doctrine/src,rules/doctrine-code-quality/src,rules/framework-migration/src,packages/file-system-rector/src,rules/elastic-search-dsl/src,rules/guzzle/src,rules/laravel/src,rules/legacy/src,rules/mysql-to-mysqli/src,rules/nette-tester-to-phpunit/src,rules/nette-to-symfony/src,rules/nette/src,packages/node-collector/src,packages/node-type-resolver/src,packages/node-name-resolver/src,rules/phpstan/src,packages/phpstan-static-type-mapper/src,rules/phpunit-symfony/src,rules/phpunit/src,rules/psr4/src,rules/php-spec-to-phpunit/src,rules/php52/src,rules/php53/src,rules/php54/src,rules/php55/src,rules/php56/src,rules/php70/src,rules/php71/src,rules/php72/src,rules/php73/src,rules/php74/src,rules/php80/src,rules/removing-static/src,rules/renaming/src,rules/restoration/src,packages/refactoring/src,rules/solid/src,rules/sensio/src,rules/shopware/src,rules/silverstripe/src,packages/static-type-mapper/src,rules/sylius/src,rules/symfony-code-quality/src,rules/symfony-phpunit/src,rules/symfony/src,rules/twig/src,rules/type-declaration/src,packages/vendor-locker/src,packages/rector-generator/src,rules/strict-code-quality/src,packages/dynamic-type-analysis/src,rules/php-deglobalize/src,rules/phalcon/src,rules/doctrine-gedmo-to-knplabs/src,packages/polyfill/src
+sonar.sources=compiler/src,src,rules/autodiscovery/src,rules/architecture/src,packages/attribute-aware-php-doc/src,packages/better-php-doc-parser/src,rules/cakephp/src,rules/celebrity/src,rules/code-quality/src,rules/coding-style/src,packages/console-differ/src,rules/dead-code/src,rules/doctrine/src,rules/doctrine-code-quality/src,rules/framework-migration/src,packages/file-system-rector/src,rules/elastic-search-dsl/src,rules/guzzle/src,rules/laravel/src,rules/legacy/src,rules/mysql-to-mysqli/src,rules/nette-tester-to-phpunit/src,rules/nette-to-symfony/src,rules/nette/src,packages/node-collector/src,packages/node-type-resolver/src,packages/node-name-resolver/src,rules/phpstan/src,packages/phpstan-static-type-mapper/src,rules/phpunit-symfony/src,rules/phpunit/src,rules/psr4/src,rules/php-spec-to-phpunit/src,rules/php52/src,rules/php53/src,rules/php54/src,rules/php55/src,rules/php56/src,rules/php70/src,rules/php71/src,rules/php72/src,rules/php73/src,rules/php74/src,rules/php80/src,rules/removing-static/src,rules/renaming/src,rules/restoration/src,packages/refactoring/src,rules/solid/src,rules/sensio/src,rules/shopware/src,packages/static-type-mapper/src,rules/sylius/src,rules/symfony-code-quality/src,rules/symfony-phpunit/src,rules/symfony/src,rules/twig/src,rules/type-declaration/src,packages/vendor-locker/src,packages/rector-generator/src,rules/strict-code-quality/src,packages/dynamic-type-analysis/src,rules/php-deglobalize/src,rules/phalcon/src,rules/doctrine-gedmo-to-knplabs/src,packages/polyfill/src
 
-sonar.tests=tests,rules/autodiscovery/tests,rules/architecture/tests,packages/better-php-doc-parser/tests,rules/cakephp/tests,rules/celebrity/tests,rules/code-quality/tests,rules/coding-style/tests,rules/dead-code/tests,rules/doctrine/tests,rules/doctrine-code-quality/tests,rules/elastic-search-dsl/tests,rules/guzzle/tests,rules/laravel/tests,rules/legacy/tests,rules/mysql-to-mysqli/tests,rules/nette-tester-to-phpunit/tests,rules/nette-to-symfony/tests,rules/nette/tests,packages/node-type-resolver/tests,utils/phpstan-extensions/src,rules/phpstan/tests,rules/phpunit-symfony/tests,rules/phpunit/tests,rules/psr4/tests,rules/php-spec-to-phpunit/tests,rules/php52/tests,rules/php53/tests,rules/php54/tests,rules/php55/tests,rules/php56/tests,rules/php70/tests,rules/php71/tests,rules/php72/tests,rules/php73/tests,rules/php74/tests,rules/php80/tests,rules/removing-static/tests,rules/renaming/tests,rules/restoration/tests,rules/solid/tests,rules/sensio/tests,rules/shopware/tests,rules/silverstripe/tests,rules/sylius/tests,rules/symfony-code-quality/tests,rules/symfony-phpunit/tests,rules/symfony/tests,rules/twig/tests,rules/type-declaration/tests,rules/strict-code-quality/tests,packages/dynamic-type-analysis/tests,rules/php-deglobalize/tests,rules/phalcon/tests,utils/documentation-generator/src,utils/phpstan-attribute-type-syncer/src,utils/phpstan-static-type-mapper-checker/src,rules/doctrine-gedmo-to-knplabs/tests,packages/polyfill/tests
+sonar.tests=tests,rules/autodiscovery/tests,rules/architecture/tests,packages/better-php-doc-parser/tests,rules/cakephp/tests,rules/celebrity/tests,rules/code-quality/tests,rules/coding-style/tests,rules/dead-code/tests,rules/doctrine/tests,rules/doctrine-code-quality/tests,rules/elastic-search-dsl/tests,rules/guzzle/tests,rules/laravel/tests,rules/legacy/tests,rules/mysql-to-mysqli/tests,rules/nette-tester-to-phpunit/tests,rules/nette-to-symfony/tests,rules/nette/tests,packages/node-type-resolver/tests,utils/phpstan-extensions/src,rules/phpstan/tests,rules/phpunit-symfony/tests,rules/phpunit/tests,rules/psr4/tests,rules/php-spec-to-phpunit/tests,rules/php52/tests,rules/php53/tests,rules/php54/tests,rules/php55/tests,rules/php56/tests,rules/php70/tests,rules/php71/tests,rules/php72/tests,rules/php73/tests,rules/php74/tests,rules/php80/tests,rules/removing-static/tests,rules/renaming/tests,rules/restoration/tests,rules/solid/tests,rules/sensio/tests,rules/shopware/tests,rules/sylius/tests,rules/symfony-code-quality/tests,rules/symfony-phpunit/tests,rules/symfony/tests,rules/twig/tests,rules/type-declaration/tests,rules/strict-code-quality/tests,packages/dynamic-type-analysis/tests,rules/php-deglobalize/tests,rules/phalcon/tests,utils/documentation-generator/src,utils/phpstan-attribute-type-syncer/src,utils/phpstan-static-type-mapper-checker/src,rules/doctrine-gedmo-to-knplabs/tests,packages/polyfill/tests
 
 # see https://docs.sonarqube.org/latest/project-administration/narrowing-the-focus/#NarrowingtheFocus-patterns
 sonar.exclusions=src/**/*.php.inc,rules/**/*.php.inc,packages/**/*.php.inc,packages/**/Fixture/**/*,rules/**/Fixture/**/*,tests/**/Source/**/*