diff --git a/tv4/tv4-tests.ts b/tv4/tv4-1.2.4-tests.ts
similarity index 100%
rename from tv4/tv4-tests.ts
rename to tv4/tv4-1.2.4-tests.ts
diff --git a/tv4/tv4-1.2.4.d.ts b/tv4/tv4-1.2.4.d.ts
new file mode 100644
index 000000000..02b7ebba2
--- /dev/null
+++ b/tv4/tv4-1.2.4.d.ts
@@ -0,0 +1,48 @@
+// Type definitions for Tiny Validator tv4 1.0.6
+// Project: https://github.com/geraintluff/tv4
+// Definitions by: Bart van der Schoor <https://github.com/Bartvds>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+interface TV4ErrorCodes {
+	[key:string]:number;
+}
+interface TV4Error {
+	code:number;
+	message:string;
+	dataPath:string;
+	schemaPath:string;
+}
+interface TV4SchemaMap {
+	[uri:string]:any;
+}
+interface TV4BaseResult {
+	missing:string[];
+	valid:boolean;
+}
+interface TV4SingleResult extends TV4BaseResult {
+	error:TV4Error;
+}
+interface TV4MultiResult extends TV4BaseResult {
+	errors:TV4Error[];
+}
+interface TV4 {
+	validateResult(data:any, schema:any):TV4SingleResult;
+	validateMultiple(data:any, schema:any):TV4MultiResult;
+
+	addSchema(uri:string, schema:any):boolean;
+	getSchema(uri:string):any;
+	normSchema(schema:any, baseUri:string):any;
+	resolveUrl(base:string, href:string):string;
+	freshApi():TV4;
+	dropSchemas():void;
+	reset():void;
+
+	getMissingUris(exp?:RegExp):string[];
+	getSchemaUris(exp?:RegExp):string[];
+	getSchemaMap():TV4SchemaMap;
+	errorCodes:TV4ErrorCodes;
+}
+declare module "tv4" {
+	var tv4: TV4
+	export = tv4;
+}
diff --git a/tv4/tv4.d.ts b/tv4/tv4.d.ts
index 02b7ebba2..3ee5a2aed 100644
--- a/tv4/tv4.d.ts
+++ b/tv4/tv4.d.ts
@@ -1,48 +1,104 @@
-// Type definitions for Tiny Validator tv4 1.0.6
+// Type definitions for Tiny Validator tv4 1.2.5
 // Project: https://github.com/geraintluff/tv4
 // Definitions by: Bart van der Schoor <https://github.com/Bartvds>
+// Definitions by: Peter Snider <https://github.com/psnider>
 // Definitions: https://github.com/borisyankov/DefinitelyTyped
 
-interface TV4ErrorCodes {
-	[key:string]:number;
-}
-interface TV4Error {
-	code:number;
-	message:string;
-	dataPath:string;
-	schemaPath:string;
-}
-interface TV4SchemaMap {
-	[uri:string]:any;
-}
-interface TV4BaseResult {
-	missing:string[];
-	valid:boolean;
-}
-interface TV4SingleResult extends TV4BaseResult {
-	error:TV4Error;
-}
-interface TV4MultiResult extends TV4BaseResult {
-	errors:TV4Error[];
-}
-interface TV4 {
-	validateResult(data:any, schema:any):TV4SingleResult;
-	validateMultiple(data:any, schema:any):TV4MultiResult;
+declare module tv4 {
+    
+    // Note that every top-level property is optional in json-schema
+    export interface JsonSchema {
+        [key: string]: any;
+        title?: string;          // used for humans only, and not used for computation
+        description?: string;    // used for humans only, and not used for computation
+        id?: string;
+        $schema?: string;
+        type?: string;
+        items?: any;
+        properties?: any;
+        patternProperties?: any; 
+        additionalProperties?: boolean;
+        required?: string[];
+        definitions?: any;
+        default?: any;
+    }
 
-	addSchema(uri:string, schema:any):boolean;
-	getSchema(uri:string):any;
-	normSchema(schema:any, baseUri:string):any;
-	resolveUrl(base:string, href:string):string;
-	freshApi():TV4;
-	dropSchemas():void;
-	reset():void;
+    export type SchemaMap = {[uri: string]: JsonSchema;};
+    // maps error codes/names to human readable error description for a single language
+    export type ErrorMap  = {[errorCode: string]: string;};
 
-	getMissingUris(exp?:RegExp):string[];
-	getSchemaUris(exp?:RegExp):string[];
-	getSchemaMap():TV4SchemaMap;
-	errorCodes:TV4ErrorCodes;
+
+    export interface ErrorCodes {
+        [key:string]:number;
+    }
+    export interface ValidationError {
+        code:number;
+        message:any;
+        dataPath?:string;
+        schemaPath?:string;
+        subErrors?: ValidationError[];
+    }
+    export interface ErrorVar extends ValidationError {
+        params: any;
+        subErrors: any;
+        stack: string;
+    }
+    export interface BaseResult {
+        missing:string[];
+        valid:boolean;
+    }
+    export interface SingleResult extends BaseResult {
+        error:ValidationError;
+    }
+    export interface MultiResult extends BaseResult {
+        errors:ValidationError[];
+    }
+    export type FormatValidationFunction = (data: any, schema: JsonSchema) => string;
+    // documentation doesnt agree with code in tv4, this type agrees with code
+    export type KeywordValidationFunction = (data: any, value: any, schema: JsonSchema, dataPointerPath: string) => string | ValidationError;
+    export type AsyncValidationCallback = (isValid: boolean, error: ValidationError) => void;
+    export interface TV4 {
+        error: ErrorVar;
+        missing: string[];
+        // primary API
+        validate(data: any, schema: JsonSchema, checkRecursive?: boolean): boolean;
+        validate(data: any, schema: JsonSchema, checkRecursive: boolean, banUnknownProperties: boolean): boolean;
+        validateResult(data: any, schema: JsonSchema, checkRecursive?: boolean): SingleResult;
+        validateResult(data: any, schema: JsonSchema, checkRecursive: boolean, banUnknownProperties: boolean): SingleResult;
+        validateMultiple(data: any, schema: JsonSchema, checkRecursive?: boolean): MultiResult;
+        validateMultiple(data: any, schema: JsonSchema, checkRecursive: boolean, banUnknownProperties: boolean): MultiResult;
+        // from including: tv4.async-jquery.js
+        validate(data: any, schema: JsonSchema, callback: AsyncValidationCallback, checkRecursive?: boolean): void;
+        validate(data: any, schema: JsonSchema, callback: AsyncValidationCallback, checkRecursive: boolean, banUnknownProperties: boolean): void;
+
+        // additional API for more complex cases
+        addSchema(schema: JsonSchema): void;
+        addSchema(uri:string, schema: JsonSchema): void;
+        getSchema(uri:string): JsonSchema;
+        getSchemaMap(): SchemaMap;
+        getSchemaUris(filter?: RegExp): string[];
+        getMissingUris(filter?: RegExp): string[];
+        dropSchemas(): void;
+        freshApi(): TV4;
+        reset(): void;
+        setErrorReporter(lang: string): void;
+        setErrorReporter(reporter: (error: ValidationError, data: any, schema: JsonSchema) => string): void;
+        language(code: string): void;
+        addLanguage(code: string, map: ErrorMap): void;
+        addFormat(format: string, validationFunction: FormatValidationFunction): void;
+        addFormat(formats: {[formatName: string]: FormatValidationFunction;}): void;
+        defineKeyword(keyword: string, validationFunction: KeywordValidationFunction): void;
+        defineError(codeName: string, codeNumber: number, defaultMessage: string): void;
+
+        // not documented
+        normSchema(schema: JsonSchema, baseUri:string):any;
+        resolveUrl(base:string, href:string):string;
+
+        errorCodes:ErrorCodes;
+    }
 }
+
 declare module "tv4" {
-	var tv4: TV4
-	export = tv4;
+    var out: tv4.TV4
+    export = out;
 }