diff --git a/crates/solidity/inputs/language/src/definition.rs b/crates/solidity/inputs/language/src/definition.rs
index 7603bbe4fd..48bb4f20a9 100644
--- a/crates/solidity/inputs/language/src/definition.rs
+++ b/crates/solidity/inputs/language/src/definition.rs
@@ -2699,6 +2699,7 @@ codegen_language_macros::compile!(Language(
                                 EnumVariant(reference = ExternalKeyword),
                                 EnumVariant(reference = PrivateKeyword),
                                 EnumVariant(reference = PublicKeyword),
+                                EnumVariant(reference = ConstantKeyword, enabled = Till("0.5.0")),
                                 EnumVariant(reference = PureKeyword, enabled = From("0.4.16")),
                                 EnumVariant(reference = ViewKeyword, enabled = From("0.4.16")),
                                 EnumVariant(reference = PayableKeyword)
diff --git a/crates/solidity/outputs/cargo/slang_solidity/src/generated/language.rs b/crates/solidity/outputs/cargo/slang_solidity/src/generated/language.rs
index 8ed57ec55b..9785cc5aeb 100644
--- a/crates/solidity/outputs/cargo/slang_solidity/src/generated/language.rs
+++ b/crates/solidity/outputs/cargo/slang_solidity/src/generated/language.rs
@@ -2709,6 +2709,13 @@ impl Language {
                 TokenKind::PublicKeyword,
             );
             choice.consider(input, result)?;
+            if !self.version_is_at_least_0_5_0 {
+                let result = self.parse_token_with_trivia::<LexicalContextType::Default>(
+                    input,
+                    TokenKind::ConstantKeyword,
+                );
+                choice.consider(input, result)?;
+            }
             if self.version_is_at_least_0_4_16 {
                 let result = self.parse_token_with_trivia::<LexicalContextType::Default>(
                     input,
diff --git a/crates/solidity/outputs/cargo/slang_solidity/src/generated/napi_interface/ast_selectors.rs b/crates/solidity/outputs/cargo/slang_solidity/src/generated/napi_interface/ast_selectors.rs
index 04d13810d6..13c7f46e39 100644
--- a/crates/solidity/outputs/cargo/slang_solidity/src/generated/napi_interface/ast_selectors.rs
+++ b/crates/solidity/outputs/cargo/slang_solidity/src/generated/napi_interface/ast_selectors.rs
@@ -1818,6 +1818,7 @@ impl Selector {
                 TokenKind::ExternalKeyword,
                 TokenKind::PrivateKeyword,
                 TokenKind::PublicKeyword,
+                TokenKind::ConstantKeyword,
                 TokenKind::PureKeyword,
                 TokenKind::ViewKeyword,
                 TokenKind::PayableKeyword,
diff --git a/crates/solidity/outputs/npm/package/src/ast/generated/ast_types.ts b/crates/solidity/outputs/npm/package/src/ast/generated/ast_types.ts
index cdb6517166..b85a9e15b2 100644
--- a/crates/solidity/outputs/npm/package/src/ast/generated/ast_types.ts
+++ b/crates/solidity/outputs/npm/package/src/ast/generated/ast_types.ts
@@ -4383,6 +4383,7 @@ export class FunctionTypeAttribute {
       case TokenKind.ExternalKeyword:
       case TokenKind.PrivateKeyword:
       case TokenKind.PublicKeyword:
+      case TokenKind.ConstantKeyword:
       case TokenKind.PureKeyword:
       case TokenKind.ViewKeyword:
       case TokenKind.PayableKeyword:
diff --git a/crates/solidity/outputs/spec/generated/grammar.ebnf b/crates/solidity/outputs/spec/generated/grammar.ebnf
index 35acad19e6..46fa682d30 100644
--- a/crates/solidity/outputs/spec/generated/grammar.ebnf
+++ b/crates/solidity/outputs/spec/generated/grammar.ebnf
@@ -890,6 +890,7 @@ FunctionTypeAttribute = INTERNAL_KEYWORD
                       | EXTERNAL_KEYWORD
                       | PRIVATE_KEYWORD
                       | PUBLIC_KEYWORD
+                      | CONSTANT_KEYWORD (* Deprecated in 0.5.0 *)
                       | PURE_KEYWORD (* Introduced in 0.4.16 *)
                       | VIEW_KEYWORD (* Introduced in 0.4.16 *)
                       | PAYABLE_KEYWORD;
diff --git a/crates/solidity/outputs/spec/generated/public/03-types/01-advanced-types.md b/crates/solidity/outputs/spec/generated/public/03-types/01-advanced-types.md
index 055227b757..6e0d93977d 100644
--- a/crates/solidity/outputs/spec/generated/public/03-types/01-advanced-types.md
+++ b/crates/solidity/outputs/spec/generated/public/03-types/01-advanced-types.md
@@ -26,7 +26,7 @@
 
 ```
 
-<pre ebnf-snippet="FunctionTypeAttribute" style="display: none;"><a href="#FunctionTypeAttribute"><span class="k">FunctionTypeAttribute</span></a><span class="o"> = </span><a href="../../01-file-structure/08-keywords#InternalKeyword"><span class="k">INTERNAL_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#ExternalKeyword"><span class="k">EXTERNAL_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PrivateKeyword"><span class="k">PRIVATE_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PublicKeyword"><span class="k">PUBLIC_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PureKeyword"><span class="k">PURE_KEYWORD</span></a><span class="o"> </span><span class="cm">(* Introduced in 0.4.16 *)</span><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#ViewKeyword"><span class="k">VIEW_KEYWORD</span></a><span class="o"> </span><span class="cm">(* Introduced in 0.4.16 *)</span><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PayableKeyword"><span class="k">PAYABLE_KEYWORD</span></a><span class="o">;</span></pre>
+<pre ebnf-snippet="FunctionTypeAttribute" style="display: none;"><a href="#FunctionTypeAttribute"><span class="k">FunctionTypeAttribute</span></a><span class="o"> = </span><a href="../../01-file-structure/08-keywords#InternalKeyword"><span class="k">INTERNAL_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#ExternalKeyword"><span class="k">EXTERNAL_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PrivateKeyword"><span class="k">PRIVATE_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PublicKeyword"><span class="k">PUBLIC_KEYWORD</span></a><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#ConstantKeyword"><span class="k">CONSTANT_KEYWORD</span></a><span class="o"> </span><span class="cm">(* Deprecated in 0.5.0 *)</span><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PureKeyword"><span class="k">PURE_KEYWORD</span></a><span class="o"> </span><span class="cm">(* Introduced in 0.4.16 *)</span><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#ViewKeyword"><span class="k">VIEW_KEYWORD</span></a><span class="o"> </span><span class="cm">(* Introduced in 0.4.16 *)</span><br /><span class="o">                      | </span><a href="../../01-file-structure/08-keywords#PayableKeyword"><span class="k">PAYABLE_KEYWORD</span></a><span class="o">;</span></pre>
 
 ```{ .ebnf #MappingType }
 
diff --git a/crates/solidity/testing/snapshots/cst_output/FunctionType/constant_state_mutability/generated/0.4.11-success.yml b/crates/solidity/testing/snapshots/cst_output/FunctionType/constant_state_mutability/generated/0.4.11-success.yml
new file mode 100644
index 0000000000..26479f5115
--- /dev/null
+++ b/crates/solidity/testing/snapshots/cst_output/FunctionType/constant_state_mutability/generated/0.4.11-success.yml
@@ -0,0 +1,32 @@
+# This file is generated automatically by infrastructure scripts. Please don't edit by hand.
+
+Source: >
+  1  │ function () constant internal returns (uint)                                     │ 0..44
+
+Errors: []
+
+Tree:
+  - (FunctionType): # "function () constant internal returns (uint)\n" (0..45)
+      - (function_keyword꞉ FunctionKeyword): "function" # (0..8)
+      - (parameters꞉ ParametersDeclaration): # " ()" (8..11)
+          - (leading_trivia꞉ Whitespace): " " # (8..9)
+          - (open_paren꞉ OpenParen): "(" # (9..10)
+          - (parameters꞉ Parameters): [] # (10..10)
+          - (close_paren꞉ CloseParen): ")" # (10..11)
+      - (attributes꞉ FunctionTypeAttributes): # " constant internal" (11..29)
+          - (item꞉ FunctionTypeAttribute): # " constant" (11..20)
+              - (leading_trivia꞉ Whitespace): " " # (11..12)
+              - (variant꞉ ConstantKeyword): "constant" # (12..20)
+          - (item꞉ FunctionTypeAttribute): # " internal" (20..29)
+              - (leading_trivia꞉ Whitespace): " " # (20..21)
+              - (variant꞉ InternalKeyword): "internal" # (21..29)
+      - (returns꞉ ReturnsDeclaration): # " returns (uint)\n" (29..45)
+          - (leading_trivia꞉ Whitespace): " " # (29..30)
+          - (returns_keyword꞉ ReturnsKeyword): "returns" # (30..37)
+          - (variables꞉ ParametersDeclaration): # " (uint)\n" (37..45)
+              - (leading_trivia꞉ Whitespace): " " # (37..38)
+              - (open_paren꞉ OpenParen): "(" # (38..39)
+              - (parameters꞉ Parameters): # "uint" (39..43)
+                  - (item꞉ Parameter) ► (type_name꞉ TypeName) ► (variant꞉ ElementaryType) ► (variant꞉ UintKeyword): "uint" # (39..43)
+              - (close_paren꞉ CloseParen): ")" # (43..44)
+              - (trailing_trivia꞉ EndOfLine): "\n" # (44..45)
diff --git a/crates/solidity/testing/snapshots/cst_output/FunctionType/constant_state_mutability/generated/0.4.11-failure.yml b/crates/solidity/testing/snapshots/cst_output/FunctionType/constant_state_mutability/generated/0.5.0-failure.yml
similarity index 100%
rename from crates/solidity/testing/snapshots/cst_output/FunctionType/constant_state_mutability/generated/0.4.11-failure.yml
rename to crates/solidity/testing/snapshots/cst_output/FunctionType/constant_state_mutability/generated/0.5.0-failure.yml