diff --git a/psalm.xml b/psalm.xml
index 510148d..feccc34 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -14,4 +14,7 @@
             <directory name="vendor" />
         </ignoreFiles>
     </projectFiles>
+    <issueHandlers>
+        <UndefinedAttributeClass errorLevel="suppress" />
+    </issueHandlers>
 </psalm>
diff --git a/src/Expansion.php b/src/Expansion.php
index 7c6f372..ef22bac 100644
--- a/src/Expansion.php
+++ b/src/Expansion.php
@@ -37,6 +37,7 @@ private function __construct(
      *
      * @param Sequence<Expression> $expressions
      */
+    #[\NoDiscard]
     public static function of(Str $template, Sequence $expressions): self
     {
         return new self(
@@ -53,6 +54,7 @@ public static function of(Str $template, Sequence $expressions): self
      *
      * @param non-empty-string $name
      */
+    #[\NoDiscard]
     public function with(string $name, string ...$values): self
     {
         if (\count($values) === 1) {
@@ -80,6 +82,7 @@ public function with(string $name, string ...$values): self
      * @param non-empty-string $name
      * @param array{string, string} ...$keys
      */
+    #[\NoDiscard]
     public function withKeys(string $name, array ...$keys): self
     {
         return new self(
@@ -94,6 +97,7 @@ public function withKeys(string $name, array ...$keys): self
         );
     }
 
+    #[\NoDiscard]
     public function expand(): Url
     {
         $url = $this->expressions->reduce(
diff --git a/src/Expression.php b/src/Expression.php
index 9c6c6a2..cdfb7e9 100644
--- a/src/Expression.php
+++ b/src/Expression.php
@@ -15,6 +15,7 @@
  */
 interface Expression
 {
+    #[\NoDiscard]
     public function expansion(): Expression\Expansion;
 
     /**
@@ -22,11 +23,15 @@ public function expansion(): Expression\Expansion;
      * @param Map<non-empty-string, list<string>> $lists
      * @param Map<non-empty-string, list<array{Name, string}>> $keys
      */
+    #[\NoDiscard]
     public function expand(Map $values, Map $lists, Map $keys): string;
 
     /**
      * @return Attempt<string>
      */
+    #[\NoDiscard]
     public function regex(): Attempt;
+
+    #[\NoDiscard]
     public function toString(): string;
 }
diff --git a/src/Expression/Expansion.php b/src/Expression/Expansion.php
index 310cc2f..385448f 100644
--- a/src/Expression/Expansion.php
+++ b/src/Expression/Expansion.php
@@ -23,6 +23,7 @@ enum Expansion
     /**
      * @psalm-pure
      */
+    #[\NoDiscard]
     public static function matchesLevel4(Str $value): bool
     {
         return $value->matches(\sprintf(
@@ -32,6 +33,7 @@ public static function matchesLevel4(Str $value): bool
         ));
     }
 
+    #[\NoDiscard]
     public function clean(Str $value): Str
     {
         $drop = match ($this) {
@@ -42,11 +44,13 @@ public function clean(Str $value): Str
         return $value->drop($drop)->dropEnd(1);
     }
 
+    #[\NoDiscard]
     public function cleanExplode(Str $value): Str
     {
         return $this->clean($value)->dropEnd(1);
     }
 
+    #[\NoDiscard]
     public function matches(Str $value): bool
     {
         return $value->matches(\sprintf(
@@ -56,6 +60,7 @@ public function matches(Str $value): bool
         ));
     }
 
+    #[\NoDiscard]
     public function matchesExplode(Str $value): bool
     {
         return $value->matches(\sprintf(
@@ -65,6 +70,7 @@ public function matchesExplode(Str $value): bool
         ));
     }
 
+    #[\NoDiscard]
     public function matchesLimit(Str $value): bool
     {
         return $value->matches(\sprintf(
@@ -74,6 +80,7 @@ public function matchesLimit(Str $value): bool
         ));
     }
 
+    #[\NoDiscard]
     public function matchesMany(Str $value): bool
     {
         return $value->matches(\sprintf(
@@ -84,6 +91,7 @@ public function matchesMany(Str $value): bool
         ));
     }
 
+    #[\NoDiscard]
     public function continuation(): self
     {
         return match ($this) {
@@ -92,6 +100,7 @@ public function continuation(): self
         };
     }
 
+    #[\NoDiscard]
     public function separator(): string
     {
         return match ($this) {
@@ -102,6 +111,7 @@ public function separator(): string
         };
     }
 
+    #[\NoDiscard]
     public function separatorRegex(): string
     {
         return match ($this->separator()) {
@@ -110,6 +120,7 @@ public function separatorRegex(): string
         };
     }
 
+    #[\NoDiscard]
     public function explodeSeparator(): string
     {
         return match ($this) {
@@ -119,6 +130,7 @@ public function explodeSeparator(): string
         };
     }
 
+    #[\NoDiscard]
     public function regex(): string
     {
         return match ($this) {
@@ -127,6 +139,7 @@ public function regex(): string
         };
     }
 
+    #[\NoDiscard]
     public function toString(): string
     {
         return match ($this) {
diff --git a/src/Expression/Level3/NamedValues.php b/src/Expression/Level3/NamedValues.php
index 10f3b24..702431c 100644
--- a/src/Expression/Level3/NamedValues.php
+++ b/src/Expression/Level3/NamedValues.php
@@ -36,6 +36,7 @@ private function __construct(
      *
      * @param Sequence<Name> $names
      */
+    #[\NoDiscard]
     public static function parameters(Sequence $names): self
     {
         return new self(Expansion::parameter, $names, true);
@@ -46,6 +47,7 @@ public static function parameters(Sequence $names): self
      *
      * @param Sequence<Name> $names
      */
+    #[\NoDiscard]
     public static function query(Sequence $names): self
     {
         return new self(Expansion::query, $names, false);
@@ -56,6 +58,7 @@ public static function query(Sequence $names): self
      *
      * @param Sequence<Name> $names
      */
+    #[\NoDiscard]
     public static function queryContinuation(Sequence $names): self
     {
         return new self(Expansion::queryContinuation, $names, false);
@@ -66,6 +69,7 @@ public static function queryContinuation(Sequence $names): self
      * @param Map<non-empty-string, list<string>> $lists
      * @param Map<non-empty-string, list<array{Name, string}>> $keys
      */
+    #[\NoDiscard]
     public function expand(Map $values, Map $lists, Map $keys): string
     {
         $expanded = $this
@@ -93,6 +97,7 @@ public function expand(Map $values, Map $lists, Map $keys): string
     /**
      * @return Attempt<string>
      */
+    #[\NoDiscard]
     public function regex(): Attempt
     {
         return $this
@@ -111,6 +116,7 @@ public function regex(): Attempt
             ->map(fn($regex) => $regex->prepend($this->expansion->regex())->toString());
     }
 
+    #[\NoDiscard]
     public function toString(): string
     {
         /** @psalm-suppress InvalidArgument */
diff --git a/src/Expression/Level4/Parse.php b/src/Expression/Level4/Parse.php
index aead883..36ce7e8 100644
--- a/src/Expression/Level4/Parse.php
+++ b/src/Expression/Level4/Parse.php
@@ -29,6 +29,7 @@ final class Parse
      *
      * @return Attempt<T>
      */
+    #[\NoDiscard]
     public static function of(
         Str $string,
         callable $standard,
diff --git a/src/Expression/Name.php b/src/Expression/Name.php
index 932b7ad..f6dee93 100644
--- a/src/Expression/Name.php
+++ b/src/Expression/Name.php
@@ -28,6 +28,7 @@ private function __construct(private string $value)
      *
      * @throws \DomainException
      */
+    #[\NoDiscard]
     public static function of(string $value): self
     {
         $characters = self::characters();
@@ -45,6 +46,7 @@ public static function of(string $value): self
      *
      * @return Attempt<self>
      */
+    #[\NoDiscard]
     public static function one(
         Str $value,
         Expansion $expansion,
@@ -67,6 +69,7 @@ public static function one(
      *
      * @return Attempt<self>
      */
+    #[\NoDiscard]
     public static function explode(
         Str $value,
         Expansion $expansion,
@@ -89,6 +92,7 @@ public static function explode(
      *
      * @return Attempt<array{self, int<1, max>}>
      */
+    #[\NoDiscard]
     public static function limit(
         Str $value,
         Expansion $expansion,
@@ -127,6 +131,7 @@ public static function limit(
      *
      * @return Attempt<Sequence<self>>
      */
+    #[\NoDiscard]
     public static function many(
         Str $value,
         Expansion $expansion,
@@ -151,6 +156,7 @@ public static function many(
     /**
      * @psalm-pure
      */
+    #[\NoDiscard]
     public static function characters(): string
     {
         return '[a-zA-Z0-9_]+';
@@ -159,6 +165,7 @@ public static function characters(): string
     /**
      * @return non-empty-string
      */
+    #[\NoDiscard]
     public function toString(): string
     {
         return $this->value;
diff --git a/src/Expressions.php b/src/Expressions.php
index 0ea5d50..bd96b9f 100644
--- a/src/Expressions.php
+++ b/src/Expressions.php
@@ -20,6 +20,7 @@ final class Expressions
      *
      * @return Attempt<Expression>
      */
+    #[\NoDiscard]
     public static function of(Str $string): Attempt
     {
         return self::expressions()
diff --git a/src/Template.php b/src/Template.php
index 16b20a9..4883da8 100644
--- a/src/Template.php
+++ b/src/Template.php
@@ -33,6 +33,7 @@ private function __construct(
      *
      * @throws \Exception
      */
+    #[\NoDiscard]
     public static function of(string $template): self
     {
         return self::attempt($template)->unwrap();
@@ -43,6 +44,7 @@ public static function of(string $template): self
      *
      *  @return Attempt<self>
      */
+    #[\NoDiscard]
     public static function attempt(string $template): Attempt
     {
         $template = Str::of($template);
@@ -57,11 +59,13 @@ public static function attempt(string $template): Attempt
      *
      *  @return Maybe<self>
      */
+    #[\NoDiscard]
     public static function maybe(string $template): Maybe
     {
         return self::attempt($template)->maybe();
     }
 
+    #[\NoDiscard]
     public function expansion(): Expansion
     {
         return Expansion::of($this->template, $this->expressions);
@@ -73,6 +77,7 @@ public function expansion(): Expansion
      *
      * @return Attempt<Map<string, string>>
      */
+    #[\NoDiscard]
     public function extract(Url $url): Attempt
     {
         /** @var Attempt<Map<string, string>> */
@@ -92,6 +97,7 @@ public function extract(Url $url): Attempt
      *
      * @return Attempt<bool>
      */
+    #[\NoDiscard]
     public function matches(Url $url): Attempt
     {
         return $this->regex()->map(
@@ -99,6 +105,7 @@ public function matches(Url $url): Attempt
         );
     }
 
+    #[\NoDiscard]
     public function toString(): string
     {
         return $this->template->toString();
diff --git a/src/UrlEncode.php b/src/UrlEncode.php
index 9d2357d..fc269ad 100644
--- a/src/UrlEncode.php
+++ b/src/UrlEncode.php
@@ -17,6 +17,7 @@ enum UrlEncode
     case everything;
     case allowReservedCharacters;
 
+    #[\NoDiscard]
     public function encode(string $string): string
     {
         if ($this === self::everything) {
@@ -35,6 +36,7 @@ public function encode(string $string): string
     /**
      * @psalm-pure
      */
+    #[\NoDiscard]
     private static function map(string $char): string
     {
         $allowed = [
diff --git a/tests/Expression/NameTest.php b/tests/Expression/NameTest.php
index b69c2c2..22f0aef 100644
--- a/tests/Expression/NameTest.php
+++ b/tests/Expression/NameTest.php
@@ -44,7 +44,7 @@ public function testThrowWhenInvalidName(): BlackBox\Proof
                 $this->expectException(\DomainException::class);
                 $this->expectExceptionMessage($string);
 
-                Name::of($string);
+                $_ = Name::of($string);
             });
     }
 }