diff --git a/tools/psalm/psalm-baseline.xml b/tools/psalm/psalm-baseline.xml
new file mode 100644
index 0000000..b905da4
--- /dev/null
+++ b/tools/psalm/psalm-baseline.xml
@@ -0,0 +1,60 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<files psalm-version="dev-master@b4fab67f3b98be02c9f7e18cf9912c4d941f5a59">
+  <file src="src/Psl/Filesystem/create_temporary_file.php">
+    <MixedArgument occurrences="2">
+      <code>SEPARATOR</code>
+      <code>SEPARATOR</code>
+    </MixedArgument>
+  </file>
+  <file src="src/Psl/Hash/Context.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>hash_update</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/Math/base_convert.php">
+    <UnnecessaryVarAnnotation occurrences="2">
+      <code>numeric-string</code>
+      <code>string</code>
+    </UnnecessaryVarAnnotation>
+  </file>
+  <file src="src/Psl/Result/Success.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>Psl\invariant_violation</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/Str/Byte/contains.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>Psl\Internal\validate_offset</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/Str/Byte/contains_ci.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>Psl\Internal\validate_offset</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/Str/Grapheme/contains.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>Psl\Internal\validate_offset</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/Str/Grapheme/contains_ci.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>Psl\Internal\validate_offset</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/Str/contains.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>Psl\Internal\validate_offset</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/Str/contains_ci.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>Psl\Internal\validate_offset</code>
+    </UnusedFunctionCall>
+  </file>
+  <file src="src/Psl/invariant.php">
+    <UnusedFunctionCall occurrences="1">
+      <code>invariant_violation</code>
+    </UnusedFunctionCall>
+  </file>
+</files>
diff --git a/tools/psalm/psalm.xml b/tools/psalm/psalm.xml
index e84fccf..ed6add8 100644
--- a/tools/psalm/psalm.xml
+++ b/tools/psalm/psalm.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<psalm totallyTyped="true" resolveFromConfigFile="true" forbidEcho="true" strictBinaryOperands="true" phpVersion="7.4" allowPhpStormGenerics="true" allowStringToStandInForClass="true" rememberPropertyAssignmentsAfterCall="false" skipChecksOnUnresolvableIncludes="false" checkForThrowsDocblock="true" checkForThrowsInGlobalScope="true" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="https://getpsalm.org/schema/config" xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd">
+<psalm totallyTyped="true" resolveFromConfigFile="true" forbidEcho="true" strictBinaryOperands="true" phpVersion="7.4" allowPhpStormGenerics="true" allowStringToStandInForClass="true" rememberPropertyAssignmentsAfterCall="false" skipChecksOnUnresolvableIncludes="false" checkForThrowsDocblock="true" checkForThrowsInGlobalScope="true" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="https://getpsalm.org/schema/config" xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
+        errorBaseline="psalm-baseline.xml">
     <projectFiles>
         <directory name="../../src" />
         <directory name="../../integration" />
@@ -7,6 +8,7 @@
             <file name="../../src/bootstrap.php" />
             <file name="../../src/preload.php" />
             <file name="../../src/Psl/Internal/Loader.php" />
+            <file name="../../src/Psl/Filesystem/create_temporary_file.php" />
         </ignoreFiles>
     </projectFiles>
 
@@ -44,8 +46,4 @@
         <RedundantCast errorLevel="suppress" />
         <RedundantCastGivenDocblockType errorLevel="suppress" />
     </issueHandlers>
-
-    <plugins>
-        <pluginClass class="Psl\Psalm\Plugin" />
-    </plugins>
 </psalm>