diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index e8d4a00..e39ea52 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -11,7 +11,7 @@ on:
 
 jobs:
   check-style:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-22.04
     steps:
     - uses: actions/checkout@v2
     - name: Report cargo version
@@ -25,7 +25,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ ubuntu-18.04, windows-2019, macos-10.15 ]
+        os: [ ubuntu-22.04, windows-2022, macos-12 ]
     steps:
     - uses: actions/checkout@v2
     - name: Build
diff --git a/Cargo.toml b/Cargo.toml
index 1c1269d..ea8bfcc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "openapiv3"
-version = "1.0.2"
+version = "1.0.3"
 authors = ["Glade Miller <glademiller@gmail.com>"]
 edition = "2018"
 license = "MIT/Apache-2.0"
@@ -12,11 +12,11 @@ description = "This crate provides data structures that represent the OpenAPI v3
 [dependencies]
 serde = {version = "1.0", features = ["derive"]}
 serde_json = "1.0"
-indexmap = {version = "1.0", features = ["serde-1"]}
+indexmap = {version = ">=1.6.1, <3.0.0", features = ["serde"]}
 
 [dev-dependencies]
-newline-converter = "0.2.0"
-serde_yaml = "0.8"
+newline-converter = "0.3.0"
+serde_yaml = "0.9"
 
 [features]
 skip_serializing_defaults = []
diff --git a/fixtures/petstore-discriminated.yaml b/fixtures/petstore-discriminated.yaml
index 06a1af9..c66a4aa 100644
--- a/fixtures/petstore-discriminated.yaml
+++ b/fixtures/petstore-discriminated.yaml
@@ -1,4 +1,3 @@
----
 openapi: 3.0.0
 info:
   title: Swagger Petstore
@@ -7,39 +6,39 @@ info:
   version: 1.0.0
   x-hash: abc123
 servers:
-  - url: "http://petstore.swagger.io/v1"
+- url: http://petstore.swagger.io/v1
 paths: {}
 components:
   schemas:
     Cat:
       description: A representation of a cat
       allOf:
-        - $ref: "#/components/schemas/Pet"
-        - type: object
-          properties:
-            huntingSkill:
-              description: The measured skill for hunting
-              type: string
-              enum:
-                - clueless
-                - lazy
-                - adventurous
-                - aggressive
-          required:
-            - huntingSkill
+      - $ref: '#/components/schemas/Pet'
+      - type: object
+        properties:
+          huntingSkill:
+            description: The measured skill for hunting
+            type: string
+            enum:
+            - clueless
+            - lazy
+            - adventurous
+            - aggressive
+        required:
+        - huntingSkill
     Dog:
       description: A representation of a dog
       allOf:
-        - $ref: "#/components/schemas/Pet"
-        - type: object
-          properties:
-            packSize:
-              description: the size of the pack the dog is from
-              type: integer
-              format: int32
-              minimum: 0
-          required:
-            - packSize
+      - $ref: '#/components/schemas/Pet'
+      - type: object
+        properties:
+          packSize:
+            description: the size of the pack the dog is from
+            type: integer
+            format: int32
+            minimum: 0
+        required:
+        - packSize
     Pet:
       discriminator:
         propertyName: petType
@@ -50,5 +49,5 @@ components:
         petType:
           type: string
       required:
-        - name
-        - petType
+      - name
+      - petType
diff --git a/src/schema.rs b/src/schema.rs
index 00c44ae..6e9c6af 100644
--- a/src/schema.rs
+++ b/src/schema.rs
@@ -68,7 +68,7 @@ pub enum Type {
     Integer(IntegerType),
     Object(ObjectType),
     Array(ArrayType),
-    Boolean {},
+    Boolean(BooleanType),
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
@@ -214,6 +214,13 @@ pub struct ArrayType {
     pub unique_items: bool,
 }
 
+#[derive(Debug, Clone, Serialize, Deserialize, Default, PartialEq)]
+#[serde(rename_all = "camelCase")]
+pub struct BooleanType {
+    #[serde(rename = "enum", default, skip_serializing_if = "Vec::is_empty")]
+    pub enumeration: Vec<Option<bool>>,
+}
+
 #[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq)]
 #[serde(rename_all = "lowercase")]
 pub enum NumberFormat {