diff --git a/crates/fuse-parser/tests/cases/pass/variable-declaration-03/ast.snap b/crates/fuse-parser/tests/cases/pass/variable-declaration-03/ast.snap
new file mode 100644
index 0000000..ca51d42
--- /dev/null
+++ b/crates/fuse-parser/tests/cases/pass/variable-declaration-03/ast.snap
@@ -0,0 +1,43 @@
+---
+source: crates/fuse-parser/tests/cases/mod.rs
+expression: parsed.chunk
+input_file: crates/fuse-parser/tests/cases/pass/variable-declaration-03/case.fuse
+---
+Some(Chunk(
+  span: Span(
+    start: 0,
+    end: 18,
+  ),
+  body: Block(
+    statements: [
+      VariableDeclaration(VariableDeclaration(
+        span: Span(
+          start: 0,
+          end: 17,
+        ),
+        kind: Let,
+        binding: BindingPattern(
+          kind: Identifier(BindingIdentifier(
+            span: Span(
+              start: 4,
+              end: 11,
+            ),
+            atom: Atom("num"),
+            mutable: true,
+          )),
+          type_annotation: None,
+          optional: false,
+        ),
+        expression: Some(NumberLiteral(NumberLiteral(
+          span: Span(
+            start: 14,
+            end: 17,
+          ),
+          raw: Atom("123"),
+          value: 123.0,
+          kind: Decimal,
+        ))),
+      )),
+    ],
+  ),
+))
diff --git a/crates/fuse-parser/tests/cases/pass/variable-declaration-03/case.fuse b/crates/fuse-parser/tests/cases/pass/variable-declaration-03/case.fuse
new file mode 100644
index 0000000..f380e0c
--- /dev/null
+++ b/crates/fuse-parser/tests/cases/pass/variable-declaration-03/case.fuse
@@ -0,0 +1 @@
+let mut num = 123
diff --git a/crates/fuse-parser/tests/cases/pass/variable-declaration-03/tokens.snap b/crates/fuse-parser/tests/cases/pass/variable-declaration-03/tokens.snap
new file mode 100644
index 0000000..014ed18
--- /dev/null
+++ b/crates/fuse-parser/tests/cases/pass/variable-declaration-03/tokens.snap
@@ -0,0 +1,102 @@
+---
+source: crates/fuse-parser/tests/cases/mod.rs
+expression: tokens
+input_file: crates/fuse-parser/tests/cases/pass/variable-declaration-03/case.fuse
+---
+[
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 0,
+        end: 3,
+      ),
+      kind: Let,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 3,
+          end: 4,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 4,
+        end: 7,
+      ),
+      kind: Mut,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 7,
+          end: 8,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 8,
+        end: 11,
+      ),
+      kind: Identifier,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 11,
+          end: 12,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 12,
+        end: 13,
+      ),
+      kind: Eq,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 13,
+          end: 14,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 14,
+        end: 17,
+      ),
+      kind: NumberLiteral,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 17,
+          end: 18,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+]
diff --git a/crates/fuse-parser/tests/cases/pass/variable-declaration-04/ast.snap b/crates/fuse-parser/tests/cases/pass/variable-declaration-04/ast.snap
new file mode 100644
index 0000000..93f509e
--- /dev/null
+++ b/crates/fuse-parser/tests/cases/pass/variable-declaration-04/ast.snap
@@ -0,0 +1,43 @@
+---
+source: crates/fuse-parser/tests/cases/mod.rs
+expression: parsed.chunk
+input_file: crates/fuse-parser/tests/cases/pass/variable-declaration-04/case.fuse
+---
+Some(Chunk(
+  span: Span(
+    start: 0,
+    end: 16,
+  ),
+  body: Block(
+    statements: [
+      VariableDeclaration(VariableDeclaration(
+        span: Span(
+          start: 0,
+          end: 15,
+        ),
+        kind: Const,
+        binding: BindingPattern(
+          kind: Identifier(BindingIdentifier(
+            span: Span(
+              start: 6,
+              end: 8,
+            ),
+            atom: Atom("PI"),
+            mutable: false,
+          )),
+          type_annotation: None,
+          optional: false,
+        ),
+        expression: Some(NumberLiteral(NumberLiteral(
+          span: Span(
+            start: 11,
+            end: 15,
+          ),
+          raw: Atom("3.14"),
+          value: 3.14,
+          kind: Float,
+        ))),
+      )),
+    ],
+  ),
+))
diff --git a/crates/fuse-parser/tests/cases/pass/variable-declaration-04/case.fuse b/crates/fuse-parser/tests/cases/pass/variable-declaration-04/case.fuse
new file mode 100644
index 0000000..85fd632
--- /dev/null
+++ b/crates/fuse-parser/tests/cases/pass/variable-declaration-04/case.fuse
@@ -0,0 +1 @@
+const PI = 3.14
diff --git a/crates/fuse-parser/tests/cases/pass/variable-declaration-04/tokens.snap b/crates/fuse-parser/tests/cases/pass/variable-declaration-04/tokens.snap
new file mode 100644
index 0000000..b1985c4
--- /dev/null
+++ b/crates/fuse-parser/tests/cases/pass/variable-declaration-04/tokens.snap
@@ -0,0 +1,83 @@
+---
+source: crates/fuse-parser/tests/cases/mod.rs
+expression: tokens
+input_file: crates/fuse-parser/tests/cases/pass/variable-declaration-04/case.fuse
+---
+[
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 0,
+        end: 5,
+      ),
+      kind: Const,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 5,
+          end: 6,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 6,
+        end: 8,
+      ),
+      kind: Identifier,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 8,
+          end: 9,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 9,
+        end: 10,
+      ),
+      kind: Eq,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 10,
+          end: 11,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+  TokenReference(
+    token: Token(
+      span: Span(
+        start: 11,
+        end: 15,
+      ),
+      kind: NumberLiteral,
+    ),
+    leading_trivia: [],
+    trailing_trivia: [
+      Token(
+        span: Span(
+          start: 15,
+          end: 16,
+        ),
+        kind: Whitespace,
+      ),
+    ],
+  ),
+]