diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__generics.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__generics.snap
index 55ac598c..9cadc4db 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__generics.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__generics.snap
@@ -1,9 +1,15 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\ntype Either<left, right> {\n    Left(left)\n    Right(right)\n}\n\ntype Interval<a> {\n    Finite(a)\n    Infinite\n}\n\nvalidator {\n  fn generics(redeemer: Either<ByteArray, Interval<Int>>, ctx: Void) {\n    True\n  }\n}\n"
+description: "Code:\n\npub type Either<left, right> {\n    Left(left)\n    Right(right)\n}\n\npub type Interval<a> {\n    Finite(a)\n    Infinite\n}\n\nvalidator generics {\n  spend(datum: Option<Data>, redeemer: Either<ByteArray, Interval<Int>>, output_reference: Data, transaction: Data) {\n    True\n  }\n}\n"
 ---
 {
-  "title": "test_module.generics",
+  "title": "test_module.generics_spend",
+  "datum": {
+    "title": "datum",
+    "schema": {
+      "$ref": "#/definitions/Data"
+    }
+  },
   "redeemer": {
     "title": "redeemer",
     "schema": {
@@ -16,6 +22,10 @@ description: "Code:\n\ntype Either<left, right> {\n    Left(left)\n    Right(rig
     "ByteArray": {
       "dataType": "bytes"
     },
+    "Data": {
+      "title": "Data",
+      "description": "Any Plutus data."
+    },
     "Int": {
       "dataType": "integer"
     },
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__list_2_tuples_as_list.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__list_2_tuples_as_list.snap
index ed44c249..6932765c 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__list_2_tuples_as_list.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__list_2_tuples_as_list.snap
@@ -1,9 +1,9 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\ntype Dict<key, value> {\n    inner: List<(ByteArray, value)>\n}\n\ntype UUID { UUID }\n\nvalidator {\n  fn list_2_tuples_as_list(redeemer: Dict<UUID, Int>, ctx: Void) {\n    True\n  }\n}\n"
+description: "Code:\n\npub type Dict<key, value> {\n    inner: List<(ByteArray, value)>\n}\n\npub type UUID { UUID }\n\nvalidator list_2_tuples_as_list {\n  mint(redeemer: Dict<UUID, Int>, policy_id: ByteArray, transaction: Data) {\n    True\n  }\n}\n"
 ---
 {
-  "title": "test_module.list_2_tuples_as_list",
+  "title": "test_module.list_2_tuples_as_list_mint",
   "redeemer": {
     "title": "redeemer",
     "schema": {
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__mint_parameterized.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__mint_parameterized.snap
index 125395a1..882d5820 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__mint_parameterized.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__mint_parameterized.snap
@@ -1,9 +1,9 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\nvalidator(utxo_ref: Int) {\n  fn mint(redeemer: Data, ctx: Data) {\n    True\n  }\n}\n// "
+description: "Code:\n\nvalidator thing(utxo_ref: Int) {\n  mint(redeemer: Data, policy_id: ByteArray, transaction: Data) {\n    True\n  }\n}\n// "
 ---
 {
-  "title": "test_module.mint",
+  "title": "test_module.thing_mint",
   "redeemer": {
     "title": "redeemer",
     "schema": {
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__nested_data.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__nested_data.snap
index e97ecaed..fd3b7257 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__nested_data.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__nested_data.snap
@@ -1,9 +1,9 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\npub type Foo {\n    foo: Data\n}\n\nvalidator {\n  fn nested_data(datum: Foo, redeemer: Int, ctx: Void) {\n    True\n  }\n}\n"
+description: "Code:\n\npub type Foo {\n    foo: Data\n}\n\nvalidator nested_data {\n  spend(datum: Option<Foo>, redeemer: Int, output_reference: Data, transaction: Data) {\n    True\n  }\n}\n"
 ---
 {
-  "title": "test_module.nested_data",
+  "title": "test_module.nested_data_spend",
   "datum": {
     "title": "datum",
     "schema": {
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__opaque_singleton_multi_variants.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__opaque_singleton_multi_variants.snap
index d3565900..247a3abe 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__opaque_singleton_multi_variants.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__opaque_singleton_multi_variants.snap
@@ -1,6 +1,6 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\npub opaque type Rational {\n  numerator: Int,\n  denominator: Int,\n}\n\nvalidator opaque_singleton_multi_variants {\n  spend(redeemer: Rational, oref: Data, ctx: Void) {\n    True\n  }\n}\n"
+description: "Code:\n\npub opaque type Rational {\n  numerator: Int,\n  denominator: Int,\n}\n\nvalidator opaque_singleton_multi_variants {\n  spend(datum: Option<Data>, redeemer: Rational, oref: Data, transaction: Data) {\n    True\n  }\n}\n"
 ---
 Schema {
     error: Error {
@@ -16,7 +16,7 @@ Schema {
             },
         ],
     },
-    location: 120..138,
+    location: 141..159,
     source_code: NamedSource {
         name: "",
         source: "<redacted>",
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_generic_types.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_generic_types.snap
index 6b20e160..d4408e21 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_generic_types.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_generic_types.snap
@@ -1,9 +1,9 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\npub type LinkedList<a> {\n  Cons(a, LinkedList<a>)\n  Nil\n}\n\npub type Foo {\n    Foo {\n        foo: LinkedList<Bool>,\n    }\n    Bar {\n        bar: Int,\n        baz: (ByteArray, List<LinkedList<Int>>)\n    }\n}\n\nvalidator {\n  fn recursive_generic_types(datum: Foo, redeemer: LinkedList<Int>, ctx: Void) {\n    True\n  }\n}\n"
+description: "Code:\n\npub type LinkedList<a> {\n  Cons(a, LinkedList<a>)\n  Nil\n}\n\npub type Foo {\n    Foo {\n        foo: LinkedList<Bool>,\n    }\n    Bar {\n        bar: Int,\n        baz: (ByteArray, List<LinkedList<Int>>)\n    }\n}\n\nvalidator recursive_generic_types {\n  spend(datum: Option<Foo>, redeemer: LinkedList<Int>, output_reference: Data, transaction: Data) {\n    True\n  }\n}\n"
 ---
 {
-  "title": "test_module.recursive_generic_types",
+  "title": "test_module.recursive_generic_types_spend",
   "datum": {
     "title": "datum",
     "schema": {
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_types.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_types.snap
index 9a931f7f..7cc67148 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_types.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__recursive_types.snap
@@ -1,9 +1,15 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\npub type Expr {\n  Val(Int)\n  Sum(Expr, Expr)\n  Mul(Expr, Expr)\n}\n\nvalidator {\n  fn recursive_types(redeemer: Expr, ctx: Void) {\n    True\n  }\n}\n"
+description: "Code:\n\npub type Expr {\n  Val(Int)\n  Sum(Expr, Expr)\n  Mul(Expr, Expr)\n}\n\nvalidator recursive_types {\n  spend(datum: Option<Data>, redeemer: Expr, output_reference: Data, transaction: Data) {\n    True\n  }\n}\n"
 ---
 {
-  "title": "test_module.recursive_types",
+  "title": "test_module.recursive_types_spend",
+  "datum": {
+    "title": "datum",
+    "schema": {
+      "$ref": "#/definitions/Data"
+    }
+  },
   "redeemer": {
     "title": "redeemer",
     "schema": {
@@ -13,6 +19,10 @@ description: "Code:\n\npub type Expr {\n  Val(Int)\n  Sum(Expr, Expr)\n  Mul(Exp
   "compiledCode": "<redacted>",
   "hash": "<redacted>",
   "definitions": {
+    "Data": {
+      "title": "Data",
+      "description": "Any Plutus data."
+    },
     "Int": {
       "dataType": "integer"
     },
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__simplified_hydra.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__simplified_hydra.snap
index 0fefe40f..f715b907 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__simplified_hydra.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__simplified_hydra.snap
@@ -1,9 +1,9 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\n/// On-chain state\ntype State {\n    /// The contestation period as a number of seconds\n    contestationPeriod: ContestationPeriod,\n    /// List of public key hashes of all participants\n    parties: List<Party>,\n    utxoHash: Hash<Blake2b_256>,\n}\n\n/// A Hash digest for a given algorithm.\ntype Hash<alg> = ByteArray\n\ntype Blake2b_256 { Blake2b_256 }\n\n/// Whatever\ntype ContestationPeriod {\n  /// A positive, non-zero number of seconds.\n  ContestationPeriod(Int)\n}\n\ntype Party =\n  ByteArray\n\ntype Input {\n    CollectCom\n    Close\n    /// Abort a transaction\n    Abort\n}\n\nvalidator {\n  fn simplified_hydra(datum: State, redeemer: Input, ctx: Data) {\n    True\n  }\n}\n"
+description: "Code:\n\n/// On-chain state\npub type State {\n    /// The contestation period as a number of seconds\n    contestationPeriod: ContestationPeriod,\n    /// List of public key hashes of all participants\n    parties: List<Party>,\n    utxoHash: Hash<Blake2b_256>,\n}\n\n/// A Hash digest for a given algorithm.\npub type Hash<alg> = ByteArray\n\npub type Blake2b_256 { Blake2b_256 }\n\n/// Whatever\npub type ContestationPeriod {\n  /// A positive, non-zero number of seconds.\n  ContestationPeriod(Int)\n}\n\npub type Party =\n  ByteArray\n\npub type Input {\n    CollectCom\n    Close\n    /// Abort a transaction\n    Abort\n}\n\nvalidator simplified_hydra {\n  spend(datum: Option<State>, redeemer: Input, output_reference: Data, transaction: Data) {\n    True\n  }\n}\n"
 ---
 {
-  "title": "test_module.simplified_hydra",
+  "title": "test_module.simplified_hydra_spend",
   "datum": {
     "title": "datum",
     "schema": {
diff --git a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__tuples.snap b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__tuples.snap
index 309e9c7b..ecaab8dd 100644
--- a/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__tuples.snap
+++ b/crates/aiken-project/src/blueprint/snapshots/aiken_project__blueprint__validator__tests__tuples.snap
@@ -1,9 +1,9 @@
 ---
 source: crates/aiken-project/src/blueprint/validator.rs
-description: "Code:\n\nvalidator {\n  fn tuples(datum: (Int, ByteArray), redeemer: (Int, Int, Int), ctx: Void) {\n    True\n  }\n}\n"
+description: "Code:\n\nvalidator tuples {\n  spend(datum: Option<(Int, ByteArray)>, redeemer: (Int, Int, Int), output_reference: Data, transaction: Data) {\n    True\n  }\n}\n"
 ---
 {
-  "title": "test_module.tuples",
+  "title": "test_module.tuples_spend",
   "datum": {
     "title": "datum",
     "schema": {
diff --git a/crates/aiken-project/src/blueprint/validator.rs b/crates/aiken-project/src/blueprint/validator.rs
index 8b936ac2..2c75f26c 100644
--- a/crates/aiken-project/src/blueprint/validator.rs
+++ b/crates/aiken-project/src/blueprint/validator.rs
@@ -7,7 +7,7 @@ use super::{
 };
 use crate::module::{CheckedModule, CheckedModules};
 use aiken_lang::{
-    ast::{Annotation, TypedArg, TypedFunction, TypedValidator},
+    ast::{well_known, Annotation, TypedArg, TypedFunction, TypedValidator},
     gen_uplc::CodeGenerator,
     plutus_version::PlutusVersion,
     tipo::Type,
@@ -124,19 +124,31 @@ impl Validator {
 
         let datum = datum
             .map(|datum| {
-                Annotated::from_type(
-                    modules.into(),
-                    tipo_or_annotation(module, datum),
-                    &mut definitions,
-                )
-                .map_err(|error| Error::Schema {
-                    error,
-                    location: datum.location,
-                    source_code: NamedSource::new(
-                        module.input_path.display().to_string(),
-                        module.code.clone(),
-                    ),
-                })
+                match datum.tipo.as_ref() {
+                    Type::App { module: module_name, name, args, .. } if module_name.is_empty() && name == well_known::OPTION => {
+                        Annotated::from_type(
+                            modules.into(),
+                            tipo_or_annotation(module, &TypedArg {
+                                arg_name: datum.arg_name.clone(),
+                                location: datum.location,
+                                annotation: datum.annotation.clone(),
+                                doc: datum.doc.clone(),
+                                is_validator_param: datum.is_validator_param,
+                                tipo:  args.first().expect("Option always have a single type argument.").clone()
+                            }),
+                            &mut definitions,
+                        )
+                        .map_err(|error| Error::Schema {
+                            error,
+                            location: datum.location,
+                            source_code: NamedSource::new(
+                                module.input_path.display().to_string(),
+                                module.code.clone(),
+                            ),
+                        })
+                    },
+                    _ => panic!("Datum isn't an option but should be; this should have been caught by the type-checker!"),
+                }
             })
             .transpose()?
             .map(|schema| Parameter {
@@ -395,7 +407,7 @@ mod tests {
         assert_validator!(
             r#"
             validator thing {
-              mint(redeemer: Data, policy_id: Data, transaction: Data) {
+              mint(redeemer: Data, policy_id: ByteArray, transaction: Data) {
                 True
               }
             }
@@ -408,7 +420,7 @@ mod tests {
         assert_validator!(
             r#"
             validator thing(utxo_ref: Int) {
-              mint(redeemer: Data, ctx: Data) {
+              mint(redeemer: Data, policy_id: ByteArray, transaction: Data) {
                 True
               }
             }
@@ -451,7 +463,7 @@ mod tests {
             }
 
             validator simplified_hydra {
-              spend(datum: State, redeemer: Input, ctx: Data) {
+              spend(datum: Option<State>, redeemer: Input, output_reference: Data, transaction: Data) {
                 True
               }
             }
@@ -464,7 +476,7 @@ mod tests {
         assert_validator!(
             r#"
             validator tuples {
-              spend(datum: (Int, ByteArray), redeemer: (Int, Int, Int), ctx: Void) {
+              spend(datum: Option<(Int, ByteArray)>, redeemer: (Int, Int, Int), output_reference: Data, transaction: Data) {
                 True
               }
             }
@@ -487,7 +499,7 @@ mod tests {
             }
 
             validator generics {
-              spend(redeemer: Either<ByteArray, Interval<Int>>, ctx: Void) {
+              spend(datum: Option<Data>, redeemer: Either<ByteArray, Interval<Int>>, output_reference: Data, transaction: Data) {
                 True
               }
             }
@@ -500,7 +512,7 @@ mod tests {
         assert_validator!(
             r#"
             validator generics {
-              mint(redeemer: a, policy_id: ByteArray, ctx: Void) {
+              mint(redeemer: a, policy_id: ByteArray, transaction: Data) {
                 True
               }
             }
@@ -519,7 +531,7 @@ mod tests {
             pub type UUID { UUID }
 
             validator list_2_tuples_as_list {
-              mint(redeemer: Dict<UUID, Int>, ctx: Void) {
+              mint(redeemer: Dict<UUID, Int>, policy_id: ByteArray, transaction: Data) {
                 True
               }
             }
@@ -538,7 +550,7 @@ mod tests {
             pub type UUID { UUID }
 
             validator list_pairs_as_map {
-              spend(redeemer: Dict<UUID, Int>, ctx: Void) {
+              spend(datum: Option<Data>, redeemer: Dict<UUID, Int>, ctx: Void) {
                 True
               }
             }
@@ -557,7 +569,7 @@ mod tests {
             pub type UUID { UUID }
 
             validator opaque_singleton_variants {
-              spend(redeemer: Dict<UUID, Int>, ctx: Void) {
+              spend(datum: Option<Data>, redeemer: Dict<UUID, Int>, output_reference: Data, transaction: Data) {
                 True
               }
             }
@@ -575,7 +587,7 @@ mod tests {
             }
 
             validator opaque_singleton_multi_variants {
-              spend(redeemer: Rational, oref: Data, ctx: Void) {
+              spend(datum: Option<Data>, redeemer: Rational, oref: Data, transaction: Data) {
                 True
               }
             }
@@ -592,7 +604,7 @@ mod tests {
             }
 
             validator nested_data {
-              spend(datum: Foo, redeemer: Int, ctx: Void) {
+              spend(datum: Option<Foo>, redeemer: Int, output_reference: Data, transaction: Data) {
                 True
               }
             }
@@ -611,7 +623,7 @@ mod tests {
             }
 
             validator recursive_types {
-              spend(redeemer: Expr, ctx: Void) {
+              spend(datum: Option<Data>, redeemer: Expr, output_reference: Data, transaction: Data) {
                 True
               }
             }
@@ -639,7 +651,7 @@ mod tests {
             }
 
             validator recursive_generic_types {
-              spend(datum: Foo, redeemer: LinkedList<Int>, ctx: Void) {
+              spend(datum: Option<Foo>, redeemer: LinkedList<Int>, output_reference: Data, transaction: Data) {
                 True
               }
             }
@@ -656,7 +668,7 @@ mod tests {
             }
 
             validator annotated_data {
-                spend(datum: Data<Foo>, redeemer: Data, ctx: Void) {
+                spend(datum: Option<Data<Foo>>, redeemer: Data, output_reference: Data, transpose: Data) {
                     True
                 }
             }
@@ -846,11 +858,13 @@ mod tests {
         let mut definitions = fixture_definitions();
         definitions.insert(
             &schema,
-            Schema::Data(Data::AnyOf(vec![Constructor {
-                index: 0,
-                fields: vec![Declaration::Referenced(Reference::new("Bool")).into()],
-            }
-            .into()]))
+            Schema::Data(Data::AnyOf(vec![
+                Constructor {
+                    index: 0,
+                    fields: vec![Declaration::Referenced(Reference::new("Bool")).into()],
+                }
+                .into(),
+            ]))
             .into(),
         );