diff --git a/composer.json b/composer.json
index 94bb0c5eff9..67e1687a34e 100644
--- a/composer.json
+++ b/composer.json
@@ -82,7 +82,6 @@
             "Psalm\\": "src/Psalm/"
         },
         "files": [
-            "src/functions.php",
             "src/spl_object_id.php"
         ]
     },
diff --git a/psalm b/psalm
index a633cb872ac..9d05b6082a4 100755
--- a/psalm
+++ b/psalm
@@ -1,6 +1,8 @@
 #!/usr/bin/env php
 <?php
 
+namespace Psalm;
+
 use Psalm\Internal\Cli\Psalm;
 
 require_once __DIR__ . '/src/Psalm/Internal/Cli/Psalm.php';
diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 62e8b0cda67..85b6ca14f2b 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -367,31 +367,6 @@
       <code>$type[0]</code>
     </PossiblyUndefinedIntArrayOffset>
   </file>
-  <file src="src/psalm-language-server.php">
-    <InternalMethod occurrences="1">
-      <code>LanguageServer::run($argv)</code>
-    </InternalMethod>
-  </file>
-  <file src="src/psalm-refactor.php">
-    <InternalMethod occurrences="1">
-      <code>Refactor::run($argv)</code>
-    </InternalMethod>
-  </file>
-  <file src="src/psalm.php">
-    <InternalMethod occurrences="1">
-      <code>Psalm::run($argv)</code>
-    </InternalMethod>
-  </file>
-  <file src="src/psalm_plugin.php">
-    <InternalMethod occurrences="1">
-      <code>Plugin::run()</code>
-    </InternalMethod>
-  </file>
-  <file src="src/psalter.php">
-    <InternalMethod occurrences="1">
-      <code>Psalter::run($argv)</code>
-    </InternalMethod>
-  </file>
   <file src="vendor/nikic/php-parser/lib/PhpParser/Node/Expr/ArrowFunction.php">
     <PossiblyUndefinedStringArrayOffset occurrences="1">
       <code>$subNodes['expr']</code>
diff --git a/psalm-language-server b/psalm-language-server
index a1869f329ab..4bc838c8a1a 100755
--- a/psalm-language-server
+++ b/psalm-language-server
@@ -1,6 +1,8 @@
 #!/usr/bin/env php
 <?php
 
+namespace Psalm;
+
 use Psalm\Internal\Cli\LanguageServer;
 
 require_once __DIR__ . '/src/Psalm/Internal/Cli/LanguageServer.php';
diff --git a/psalm-plugin b/psalm-plugin
index 6f7d7c5ece0..5ab7a2b4d10 100755
--- a/psalm-plugin
+++ b/psalm-plugin
@@ -1,6 +1,8 @@
 #!/usr/bin/env php
 <?php
 
+namespace Psalm;
+
 use Psalm\Internal\Cli\Plugin;
 
 require_once __DIR__ . '/src/Psalm/Internal/Cli/Plugin.php';
diff --git a/psalm-refactor b/psalm-refactor
index 5bdd7f63b65..3e48e610728 100755
--- a/psalm-refactor
+++ b/psalm-refactor
@@ -1,6 +1,8 @@
 #!/usr/bin/env php
 <?php
 
+namespace Psalm;
+
 use Psalm\Internal\Cli\Refactor;
 
 require_once __DIR__ . '/src/Psalm/Internal/Cli/Refactor.php';
diff --git a/psalm.xml.dist b/psalm.xml.dist
index 4d43b591aff..bdbaaab6da5 100644
--- a/psalm.xml.dist
+++ b/psalm.xml.dist
@@ -25,6 +25,11 @@
         <directory name="src"/>
         <directory name="tests"/>
         <directory name="examples"/>
+        <file name="psalm"/>
+        <file name="psalm-language-server"/>
+        <file name="psalm-plugin"/>
+        <file name="psalm-refactor"/>
+        <file name="psalter"/>
         <ignoreFiles>
             <file name="src/Psalm/Internal/PhpTraverser/CustomTraverser.php"/>
             <file name="tests/ErrorBaselineTest.php"/>
diff --git a/psalter b/psalter
index c36c93fec99..8fb9dd3e648 100755
--- a/psalter
+++ b/psalter
@@ -1,6 +1,8 @@
 #!/usr/bin/env php
 <?php
 
+namespace Psalm;
+
 use Psalm\Internal\Cli\Psalter;
 
 require_once __DIR__ . '/src/Psalm/Internal/Cli/Psalter.php';
diff --git a/src/command_functions.php b/src/command_functions.php
deleted file mode 100644
index 4a797d8ab7e..00000000000
--- a/src/command_functions.php
+++ /dev/null
@@ -1,88 +0,0 @@
-<?php
-
-namespace Psalm;
-
-use Composer\Autoload\ClassLoader;
-use Psalm\Internal\CliUtils;
-
-// phpcs:disable PSR1.Files.SideEffects
-require_once __DIR__ . '/Psalm/Internal/CliUtils.php';
-
-/** @deprecated going to be removed in Psalm 5 */
-function requireAutoloaders(string $current_dir, bool $has_explicit_root, string $vendor_dir): ?ClassLoader
-{
-    return CliUtils::requireAutoloaders($current_dir, $has_explicit_root, $vendor_dir);
-}
-
-/** @deprecated going to be removed in Psalm 5 */
-function getVendorDir(string $current_dir): string
-{
-    return CliUtils::getVendorDir($current_dir);
-}
-
-/**
- * @return list<string>
- * @deprecated going to be removed in Psalm 5
- */
-function getArguments(): array
-{
-    return CliUtils::getArguments();
-}
-
-/**
- * @param  string|array|null|false $f_paths
- *
- * @return list<string>|null
- * @deprecated going to be removed in Psalm 5
- */
-function getPathsToCheck($f_paths): ?array
-{
-    return CliUtils::getPathsToCheck($f_paths);
-}
-
-/**
- * @psalm-pure
- * @deprecated going to be removed in Psalm 5
- */
-function getPsalmHelpText(): string
-{
-    return CliUtils::getPsalmHelpText();
-}
-
-/** @deprecated going to be removed in Psalm 5 */
-function initialiseConfig(
-    ?string $path_to_config,
-    string $current_dir,
-    string $output_format,
-    ?ClassLoader $first_autoloader,
-    bool $create_if_non_existent = false
-): Config {
-    return CliUtils::initializeConfig(
-        $path_to_config,
-        $current_dir,
-        $output_format,
-        $first_autoloader,
-        $create_if_non_existent
-    );
-}
-
-/** @deprecated going to be removed in Psalm 5 */
-function update_config_file(Config $config, string $config_file_path, string $baseline_path): void
-{
-    CliUtils::updateConfigFile($config, $config_file_path, $baseline_path);
-}
-
-/** @deprecated going to be removed in Psalm 5 */
-function get_path_to_config(array $options): ?string
-{
-    return CliUtils::getPathToConfig($options);
-}
-
-/**
- * @psalm-pure
- * @deprecated going to be removed in Psalm 5
- */
-function getMemoryLimitInBytes(): int
-{
-    return CliUtils::getMemoryLimitInBytes();
-}
diff --git a/src/functions.php b/src/functions.php
deleted file mode 100644
index a44e53cc7e1..00000000000
--- a/src/functions.php
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-
-namespace Psalm;
-
-use Webmozart\PathUtil\Path;
-
-/**
- * @deprecated Use {@see Webmozart\PathUtil\Path::isAbsolute}. No longer used by Psalm, going to be removed in Psalm 5
- */
-function isAbsolutePath(string $path): bool
-{
-    return Path::isAbsolute($path);
-}
diff --git a/src/psalm-language-server.php b/src/psalm-language-server.php
deleted file mode 100644
index a303e2d3284..00000000000
--- a/src/psalm-language-server.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-/**
- * @deprecated This file is going to be removed in Psalm 5
- */
-use Psalm\Internal\Cli\LanguageServer;
-
-/** */
-require_once __DIR__ . '/Psalm/Internal/Cli/LanguageServer.php';
-LanguageServer::run($argv);
diff --git a/src/psalm-refactor.php b/src/psalm-refactor.php
deleted file mode 100644
index 6943cd1312a..00000000000
--- a/src/psalm-refactor.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-/**
- * @deprecated This file is going to be removed in Psalm 5
- */
-use Psalm\Internal\Cli\Refactor;
-
-/** */
-require_once __DIR__ . '/Psalm/Internal/Cli/Refactor.php';
-Refactor::run($argv);
diff --git a/src/psalm.php b/src/psalm.php
deleted file mode 100644
index dabe29087c9..00000000000
--- a/src/psalm.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-/**
- * @deprecated This file is going to be removed in Psalm 5
- */
-use Psalm\Internal\Cli\Psalm;
-
-/** */
-require __DIR__ . '/Psalm/Internal/Cli/Psalm.php';
-Psalm::run($argv);
diff --git a/src/psalm_plugin.php b/src/psalm_plugin.php
deleted file mode 100644
index 649288296cf..00000000000
--- a/src/psalm_plugin.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-/**
- * @deprecated This file is going to be removed in Psalm 5
- */
-use Psalm\Internal\Cli\Plugin;
-
-/** */
-require_once __DIR__ . '/Psalm/Internal/Cli/Plugin.php';
-Plugin::run();
diff --git a/src/psalter.php b/src/psalter.php
deleted file mode 100644
index ce0271d2bab..00000000000
--- a/src/psalter.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-/**
- * @deprecated This file is going to be removed in Psalm 5
- */
-use Psalm\Internal\Cli\Psalter;
-
-/** */
-require_once __DIR__ . '/Psalm/Internal/Cli/Psalter.php';
-Psalter::run($argv);