diff --git a/index.d.ts b/index.d.ts
index 8f93174..42cd3ea 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -23,9 +23,7 @@ declare namespace tss {
         private createService();
         private getTypeScriptBinDir();
         private getDefaultLibFileName(options);
-        private getFile(outputFiles, fileName);
         private toJavaScript(service, fileName);
-        private normalizeSlashes(path);
         private formatDiagnostics(diagnostics);
     }
 }
diff --git a/index.ts b/index.ts
index 0bdeb4e..7db70a4 100644
--- a/index.ts
+++ b/index.ts
@@ -27,14 +27,17 @@ namespace tss {
          * @constructor
          */
         constructor(options: ts.CompilerOptions = {}, private doSemanticChecks = true) {
-            // accept null
-            options = options || {};
+            options = Object.assign({}, options);
             if (options.target == null) {
                 options.target = ts.ScriptTarget.ES5;
             }
             if (options.module == null) {
                 options.module = ts.ModuleKind.None;
             }
+            if (options.sourceMap) {
+                options.sourceMap = false;
+                options.inlineSourceMap = true;
+            }
             this.options = options;
         }
 
@@ -113,7 +116,7 @@ namespace tss {
                 // TODO: Use options.newLine
                 getNewLine: () => os.EOL,
                 log: (message: string) => console.log(message),
-                trace: (message: string) => console.debug(message),
+                trace: (message: string) => console.trace(message),
                 error: (message: string) => console.error(message),
                 readFile: readFile,
                 fileExists: fileExists
@@ -154,31 +157,6 @@ namespace tss {
             }
         }
 
-        /**
-         * converts {"version":3,"file":"file.js","sourceRoot":"","sources":["file.ts"],"names":[],
-         *    "mappings":"AAAA,IAAI,CAAC,GAAG,MAAM,CAAC"}
-         * to {"version":3,"sources":["foo/test.ts"],"names":[],
-         *    "mappings":"AAAA,IAAI,CAAC,GAAG,MAAM,CAAC","file":"foo/test.ts","sourcesContent":["var x = 'test';"]}
-         * derived from : https://github.com/thlorenz/convert-source-map
-         * @internal
-         */
-        private getInlineSourceMap(mapText: string, fileName: string): string {
-            let sourceMap = JSON.parse(mapText);
-            sourceMap.file = fileName;
-            sourceMap.sources = [fileName];
-            sourceMap.sourcesContent = [this.files[fileName].text];
-            delete sourceMap.sourceRoot;
-            return JSON.stringify(sourceMap);
-        }
-
-        private getFile (outputFiles: ts.OutputFile[], fileName: string): ts.OutputFile {
-            const files = outputFiles.filter((file) => {
-              const full = this.normalizeSlashes(path.resolve(process.cwd(), fileName));
-              return file.name === fileName || file.name === full;
-            });
-            return files[0];
-        }
-
         private toJavaScript(service: ts.LanguageService, fileName: string): string {
             let output = service.getEmitOutput(fileName);
 
@@ -193,37 +171,12 @@ namespace tss {
                 throw new Error(this.formatDiagnostics(allDiagnostics));
             }
 
-            let outDir = (this.options && this.options.outDir) ? this.options.outDir : '';
-            let fileNameWithoutRoot = 'rootDir' in this.options ? fileName.replace(new RegExp('^' + this.options.rootDir), '') : fileName;
-            let outputFileName: string;
-            if (this.options.jsx === ts.JsxEmit.Preserve) {
-                outputFileName = path.join(outDir, fileNameWithoutRoot.replace(/\.tsx$/, '.jsx'));
-            } else {
-                outputFileName = path.join(outDir, fileNameWithoutRoot.replace(/\.tsx?$/, '.js'));
-            }
-            // for Windows #37
-            outputFileName = this.normalizeSlashes(outputFileName);
-            let file = this.getFile(output.outputFiles, outputFileName);
-            let text = file.text;
-
-            // If we have sourceMaps convert them to inline sourceMaps
-            if (this.options.sourceMap) {
-                let sourceMapFileName = outputFileName + '.map';
-                let sourceMapFile = this.getFile(output.outputFiles, sourceMapFileName)
-
-                // Transform sourcemap
-                let sourceMapText = sourceMapFile.text;
-                sourceMapText = this.getInlineSourceMap(sourceMapText, fileName);
-                let base64SourceMapText = new Buffer(sourceMapText).toString('base64');
-                let sourceMapComment = '//# sourceMappingURL=data:application/json;base64,' + base64SourceMapText;
-                text = text.replace('//# sourceMappingURL=' + path.basename(sourceMapFileName), sourceMapComment);
+            if (output.outputFiles.length !== 1) {
+                const names = output.outputFiles.map(_ => _.name);
+                throw new Error(`Output should be only 1 file, but ${names.length} files: ${names.join(', ')}`);
             }
 
-            return text;
-        }
-
-        private normalizeSlashes(path: string): string {
-            return path.replace(/\\/g, "/");
+            return output.outputFiles[0].text;
         }
 
         private formatDiagnostics(diagnostics: ts.Diagnostic[]): string {
diff --git a/test/test.js b/test/test.js
index a97381e..5fd883a 100644
--- a/test/test.js
+++ b/test/test.js
@@ -157,16 +157,16 @@ describe('typescript-simple', function() {
         });
     });
 
-    context('tss sourceMaps option is true', function() {
+    context('`sourceMap` option is true', function() {
         var tss;
         beforeEach(function() {
             tss = new TypeScriptSimple({target: ts.ScriptTarget.ES5, sourceMap: true}, false);
         });
 
-        it('should result in inline sourceMaps', function() {
+        it('should result in `inlineSourceMap', function() {
             var src = 'var x = "test";';
             var srcFile = 'foo/test.ts';
-            var sourceMap = '{"version":3,"file":"foo/test.ts","sources":["foo/test.ts"],"names":[],"mappings":"AAAA,IAAI,CAAC,GAAG,MAAM,CAAC","sourcesContent":["var x = \\"test\\";"]}';
+            var sourceMap = '{"version":3,"file":"test.js","sources":["test.ts"],"sourceRoot":"","names":[],"mappings":"AAAA,IAAI,CAAC,GAAG,MAAM,CAAC"}';
             var expectedPrefix = 'var x = "test";' + eol + '//# sourceMappingURL=data:application/json;base64,';
             var actual = tss.compile(src, srcFile);
             var match = /(^[\s\S]*;base64,)(.*)$/.exec(actual);
@@ -176,13 +176,13 @@ describe('typescript-simple', function() {
         });
     });
 
-    context('native inlineSourceMap option is true', function() {
+    context('native `inlineSourceMap` option is true', function() {
         var tss;
         beforeEach(function() {
             tss = new TypeScriptSimple({target: ts.ScriptTarget.ES5, inlineSourceMap: true, inlineSources: true}, false);
         });
 
-        it('should result in inline sourceMaps', function() {
+        it('should result in inline sourceMap', function() {
             var src = 'var x = "test";';
             var srcFile = 'foo/test.ts';
             var sourceMap = '{"version":3,"file":"test.js","sourceRoot":"","sources":["test.ts"],"names":[],"mappings":"AAAA,IAAI,CAAC,GAAG,MAAM,CAAC","sourcesContent":["var x = \\"test\\";"]}';
@@ -238,11 +238,11 @@ describe('typescript-simple', function() {
             assert.equal(tss.compile(src), expected);
         });
 
-        it('should result in inline sourceMaps', function() {
+        it('should result in inline sourceMap', function() {
             var tss = new TypeScriptSimple({jsx: ts.JsxEmit.Preserve, sourceMap: true});
             var src = 'var foo: any = <bar />;';
             var srcFile = 'foo/test.tsx';
-            var sourceMap = '{"version":3,"file":"foo/test.tsx","sources":["foo/test.tsx"],"names":[],"mappings":"AAAA,IAAI,GAAG,GAAQ,CAAC,GAAG,GAAG,CAAC","sourcesContent":["var foo: any = <bar />;"]}';
+            var sourceMap = '{"version":3,"file":"test.jsx","sourceRoot":"","sources":["test.tsx"],"names":[],"mappings":"AAAA,IAAI,GAAG,GAAQ,CAAC,GAAG,GAAG,CAAC"}';
             var expectedPrefix = 'var foo = <bar />;' + eol + '//# sourceMappingURL=data:application/json;base64,';
             var actual = tss.compile(src, srcFile);
             var match = /(^[\s\S]*;base64,)(.*)$/.exec(actual);
diff --git a/tsconfig.json b/tsconfig.json
index de4d012..eb4476d 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -2,6 +2,9 @@
     "compilerOptions": {
         "target": "es5",
         "module": "commonjs",
+        "lib": [
+            "ES6"
+        ],
         "declaration": true,
         "removeComments": false,
         "stripInternal": true,