diff --git a/src/openapi/codegen.nim b/src/openapi/codegen.nim
index 2801c62..08f7bc4 100644
--- a/src/openapi/codegen.nim
+++ b/src/openapi/codegen.nim
@@ -11,6 +11,7 @@ import parser
 import paths
 
 from schema2 import OpenApi2
+from schema3 import OpenApi3
 
 const MAKETYPES = false
 when MAKETYPES:
@@ -1259,6 +1260,10 @@ proc init*(generator: var Generator; content: string) =
     if generator.js["swagger"].getStr != "2.0":
       error "we only know how to parse openapi-2.0 atm"
     generator.schema = OpenApi2
+  elif "openapi" in generator.js:
+    if not generator.js["openapi"].getStr.startsWith("3."):
+      error "we only know how to parse openapi-3.xxx atm"
+    generator.schema = OpenApi3
   else:
     error "no swagger version found in the input"
 
diff --git a/src/openapi/parser.nim b/src/openapi/parser.nim
index b59777e..482791a 100644
--- a/src/openapi/parser.nim
+++ b/src/openapi/parser.nim
@@ -168,7 +168,7 @@ proc parseField*(ftype: FieldTypeDef; js: JsonNode): ParserResult =
     result = ftype.a.parseField(js)
     if not result.ok:
       result = ftype.b.parseField(js)
-  of List:
+  of List, Map:
     foreach j in js.items of JsonNode:
       result = ftype.member.parseField(j)
       if not result.ok:
diff --git a/src/openapi/schema3.nim b/src/openapi/schema3.nim
new file mode 100644
index 0000000..f6c7445
--- /dev/null
+++ b/src/openapi/schema3.nim
@@ -0,0 +1,401 @@
+# Adapted from schema2
+
+# this is rather critical for reasons
+import tables
+
+import spec
+
+
+template `<~`(name: untyped; fields: openArray[(FieldName, FieldTypeDef)]) =
+  # it's a var because we sometimes need to mutate it
+  var name {.compileTime.} = `fields`.newSchema
+
+template `<~`(name: untyped; ftype: FieldTypeDef) =
+  # it's a var because we sometimes need to mutate it
+  var name {.compileTime.} = ftype
+
+Contact <~ {
+  "name": optional JString,
+  "url": optional JString,
+  "email": optional JString,
+
+  "^x-": patterned optional anything {},
+}
+
+License <~ {
+  "name": required JString,
+
+  "url": optional JString,
+
+  "^x-": patterned optional anything {},
+}
+
+Info <~ {
+  "title": required JString,
+  "version": required JString,
+
+  "description": optional JString,
+  "termsOfService": optional JString,
+  "contact": optional Contact,
+  "license": optional License,
+
+  "^x-": patterned optional anything {},
+}
+
+## An object representing a Server Variable for server URL template substitution.
+ServerVariable <~ {
+  "default": required JString,
+
+  "enum": optional JString.arrayOf, ## should not be empty
+  "description": optional JString,
+
+  "^x-": patterned optional anything {},
+}
+
+EnumArray <~ arrayOf(anything {})
+
+ServerObject <~ {
+  "url": required JString,
+
+  "description": optional JString,
+  "variables": optional ServerVariable.mapOf,
+
+  "^x-": patterned optional anything {},
+}
+
+Reference <~ {
+  "$ref": required JString,
+}
+
+XmlObject <~ {
+  "name": optional JString,
+  "namespace": optional JString,
+  "prefix": optional JString,
+  "attribute": optional JBool,
+  "wrapped": optional JBool,
+
+  "^x-": optional patterned anything {},
+}
+
+ExternalDocs <~ {
+  "url": required JString,
+
+  "description": optional JString,
+
+  "^x-": patterned anything {},
+}
+
+Items <~ {
+  "type": required JString,
+
+  "format": optional JString,
+  "collectionFormat": optional JString,
+  "default": unpatterned optional anything {},
+  "maximum": optional JInt,
+  "exclusiveMaximum": optional JInt,
+  "minimum": optional JInt,
+  "exclusiveMinimum": optional JBool,
+  "maxLength": optional JInt,
+  "minLength": optional JInt,
+  "pattern": optional JString,
+  "maxItems": optional JInt,
+  "minItems": optional JInt,
+  "uniqueItems": optional JBool,
+  "enum": optional EnumArray,
+  "multipleOf": optional JInt,
+
+  "^x-": optional patterned anything {},
+}
+
+SchemaObject <~ {
+  "$ref": optional Reference,
+
+  # per json:
+  "type": required JString,
+  # could be "array" or "file", too ?  openapi unclear on this.
+
+  "format": optional JString,
+  "title": optional JString,
+  "description": optional JString,
+  "default": optional anything {},  # it must match the "type" above
+  "multipleOf": optional JInt,
+
+  # per swagger:
+  "discriminator": optional JString,
+  "readOnly": optional JBool,
+  "xml": optional XmlObject,
+  "externalDocs": optional ExternalDocs,
+  "example": optional unpatterned anything {},
+
+  # from items
+  "items": optional Items,
+  "maximum": optional JInt,
+  "exclusiveMaximum": optional JInt,
+  "minimum": optional JInt,
+  "exclusiveMinimum": optional JBool,
+  "maxLength": optional JInt,
+  "minLength": optional JInt,
+  "pattern": optional JString,
+  "maxItems": optional JInt,
+  "minItems": optional JInt,
+  "uniqueItems": optional JBool,
+
+  # extra per json schema
+  "maxProperties": optional JInt,
+  "minProperties": optional JInt,
+  "required": optional JString.arrayOf,
+  "enum": optional EnumArray,
+  "multipleOf": optional JInt,
+
+  "^x-": optional patterned anything {},
+}
+
+
+ParameterObject <~ {
+  "description": required JString,
+  "required": optional JBool, # default false, required for in=="path"
+
+  # if in is "body", then this is required XXX FIXME
+  "schema": optional SchemaObject,
+  # otherwise, as per Items:
+  "type": required JString,
+  "format": optional JString,
+  "collectionFormat": optional JString,
+  "default": unpatterned optional anything {},
+  "maximum": optional JInt,
+  "exclusiveMaximum": optional JInt,
+  "minimum": optional JInt,
+  "exclusiveMinimum": optional JBool,
+  "maxLength": optional JInt,
+  "minLength": optional JInt,
+  "pattern": optional JString,
+  "maxItems": optional JInt,
+  "minItems": optional JInt,
+  "uniqueItems": optional JBool,
+  "enum": optional EnumArray,
+  "multipleOf": optional JInt,
+
+  # these differ from Items
+  "allowEmptyValue": optional JBool,
+
+  "name": required JString,
+  "in": required JString,
+}
+
+Header <~ {
+  "description": required JString,
+  "required": optional JBool, # default false, required for in=="path"
+
+  # if in is "body", then this is required XXX FIXME
+  "schema": optional SchemaObject,
+  # otherwise, as per Items:
+  "type": required JString,
+  "format": optional JString,
+  "collectionFormat": optional JString,
+  "default": unpatterned optional anything {},
+  "maximum": optional JInt,
+  "exclusiveMaximum": optional JInt,
+  "minimum": optional JInt,
+  "exclusiveMinimum": optional JBool,
+  "maxLength": optional JInt,
+  "minLength": optional JInt,
+  "pattern": optional JString,
+  "maxItems": optional JInt,
+  "minItems": optional JInt,
+  "uniqueItems": optional JBool,
+  "enum": optional EnumArray,
+  "multipleOf": optional JInt,
+
+  # these differ from Items
+  "allowEmptyValue": optional JBool,
+}
+
+Headers <~ {
+  "{name}": optional Header,
+}
+
+ExampleObject <~ {
+  "summary": optional JString,
+  "description": optional JString,
+  "value": optional anything(),
+  "externalValue": optional JString,
+}
+
+Response <~ {
+  "description": required JString,
+  "schema": optional SchemaObject,
+  "headers": optional Headers,
+  "examples": optional ExampleObject,
+}
+
+Responses <~ {
+  "default": optional (Response | Reference),
+
+  "{http status code}": optional (Response | Reference),
+  "^x-": optional patterned anything {},
+}
+
+
+## Holds a set of reusable objects for different aspects of the OAS.
+## All objects defined within the components object will have no effect on the
+## API unless they are explicitly referenced from properties outside the components object.
+Components <~ {
+  "schemas": (SchemaObject | Reference).mapOf,
+  "responses": (Response | Reference).mapOf,
+
+}
+
+# recursive type in case the parent type is array, in which
+# case this field reflects the type of array members
+static:
+  Items["items"] = optional Items
+
+static:
+  # recursion thanks to json schema
+  SchemaObject["allOf"] = optional SchemaObject.arrayOf
+
+  # either a bool, or a SchemaObject; these are table semantics
+  SchemaObject["additionalProperties"] = optional (JBool | SchemaObject)
+
+  # these are basic object field semantics; arbitrary values
+  SchemaObject["properties"] = optional SchemaObject
+
+SecurityRequirement <~ {
+  "{name}": optional JString.arrayOf,
+}
+
+Example <~ {
+  "{mime type}": optional anything {},
+}
+
+SchemesArray <~ JString.arrayOf
+
+TagObject <~ {
+  "name": required JString,
+  "description": optional Jstring,
+  "externalDocs": optional ExternalDocs,
+
+  "^x-": patterned optional anything {},
+}
+
+EncodingObject <~ {
+  "contentType": optional JString,
+  "headers": optional (Header | Reference).mapOf,
+  "style": optional JString,
+  "explode": optional JBool,
+  "allowReserved": optional JBool,
+
+  "^x-": patterned optional anything {},
+}
+
+MediaTypeObject <~ {
+  "encoding": optional EncodingObject.mapOf,
+  "example": optional anything(),
+  "schema": optional (SchemaObject | Reference),
+  "examples": optional (ExampleObject | Reference).mapOf,
+
+  "^x-": optional patterned anything {},
+}
+
+RequestBodyObject <~ {
+  "content": required MediaTypeObject.mapOf,
+
+  "description": optional JString,
+  "required": optional JBool,
+
+  "^x-": patterned optional anything {},
+}
+
+ParameterObjectDefinition <~ {
+  "{name}": optional ParameterObject,
+}
+
+Operation <~ {
+  "responses": required Responses,
+
+  "tags": optional TagObject.arrayOf,
+  "summary": optional JString,
+  "description": optional JString,
+  "externalDocs": optional ExternalDocs,
+  "operationId": optional JString,
+  "consumes": optional JString.arrayOf,
+  "produces": optional JString.arrayOf,
+  "parameters": optional (ParameterObject | Reference).arrayOf,
+  "requestBody": optional (RequestBodyObject | Reference),
+  # "schemes": optional SchemesArray,
+  "deprecated": optional JBool,
+  "security": optional SecurityRequirement.arrayOf,
+  "servers": optional ServerObject.arrayOf,
+
+  "^x-": optional patterned anything {},
+}
+
+PathItem <~ {
+  "$ref": optional JString,
+  "get": optional Operation,
+  "put": optional Operation,
+  "post": optional Operation,
+  "delete": optional Operation,
+  "options": optional Operation,
+  "head": optional Operation,
+  "patch": optional Operation,
+  "parameters": optional (ParameterObject | Reference).arrayOf,
+
+  "^x-": patterned optional anything {},
+}
+
+CallbackObject <~ {
+  "{expression}": required PathItem,
+}
+
+# break recursion
+static:
+  Operation["callbacks"] = optional (CallbackObject | Reference).mapOf
+
+SecurityScope <~ {
+  "{name}": optional JString,
+
+  "^x-": patterned optional anything {},
+}
+
+SecurityScheme <~ {
+  "name": required JString,
+  "in": required JString,
+  "flow": required JString,
+  "authorizationUrl": required JString,
+  "tokenUrl": required JString,
+  "scopes": required SecurityScope.arrayOf,
+
+  "type": optional JString,
+  "description": optional JString,
+
+  "^x-": patterned optional anything {},
+}
+
+SecurityDefinitions <~ {
+  "{name}": optional SecurityScheme,
+}
+
+Definitions <~ {
+  "{name}": optional SchemaObject,
+}
+
+Paths <~ {
+  "/{path}": optional PathItem,
+
+  "^x-": patterned anything {},
+}
+
+OpenApi3 <~ {
+  "openapi": required JString,
+  "info": required Info,
+  "paths": required Paths,
+  "servers": optional ServerObject.arrayOf,
+  "components": optional Components,
+  "security": optional SecurityRequirement.arrayOf,
+  "tags": optional TagObject.arrayOf,
+  "externalDocs": optional ExternalDocs,
+
+  "^x-": patterned optional anything {},
+}
+export OpenApi3
diff --git a/src/openapi/spec.nim b/src/openapi/spec.nim
index 2c78ef3..5c0cc33 100644
--- a/src/openapi/spec.nim
+++ b/src/openapi/spec.nim
@@ -24,6 +24,7 @@ type
     List      ## an array
     Either    ## one of 2+ possible values
     Complex   ## a map-like object
+    Map       ## a uniform map object
   FieldTypeDef* = ref object ## the type for any given value
     kinds*: set[JsonNodeKind]
     pattern*: bool
@@ -37,6 +38,8 @@ type
       member*: FieldTypeDef
     of Complex:
       schema*: Schema
+    of Map:
+      mapMember*: FieldTypeDef
   ## string values as per the spec
   HttpOpName* = enum
     Get = "get"
@@ -116,6 +119,9 @@ proc newFieldTypeDef*(kind: FieldType; kinds: set[JsonNodeKind]={};
   of Either:
     # TODO: maybe perform an assertion here?
     result = FieldTypeDef(kind: Either, kinds: {}, pattern: pattern, required: required)
+  of Map:
+    result = FieldTypeDef(kind: Map, kinds: {JObject}, pattern: pattern, required: required,
+                          mapMember: member)
   #else:
   # raise newException(Defect, "unimplemented " & $kind & " field")
 
@@ -142,6 +148,8 @@ converter toJsonNodeKind*(f: FieldTypeDef): JsonNodeKind =
     result = JObject
   of List:
     result = JArray
+  of Map:
+    result = JObject
   of Anything:
     result = JNull
   of Either:
@@ -174,6 +182,8 @@ proc paint(src: FieldTypeDef; dst: FieldTypeDef) =
     dst.schema = src.schema
   of List:
     dst.member = src.member
+  of Map:
+    dst.mapMember = src.mapMember
   of Either:
     dst.a = src.a
     dst.b = src.b
@@ -183,6 +193,10 @@ proc arrayOf*(member: FieldTypeDef): FieldTypeDef =
   result = FieldTypeDef(kind: List, kinds: {JArray}, member: member,
     pattern: member.pattern, required: member.required)
 
+proc mapOf*(member: FieldTypeDef): FieldTypeDef =
+  result = FieldTypeDef(kind: Map, kinds: {JObject}, mapMember: member,
+    pattern: member.pattern, required: member.required)
+
 converter toFieldTypeDef*(list: array[1, FieldTypeDef]): FieldTypeDef =
   result = list[0].arrayOf