diff --git a/package.json b/package.json
index 6f176708be500..24829b260106f 100644
--- a/package.json
+++ b/package.json
@@ -163,7 +163,6 @@
   },
   "devDependencies": {
     "@elastic/eslint-config-kibana": "0.0.3",
-    "Nonsense": "0.1.2",
     "angular-mocks": "1.4.7",
     "auto-release-sinon": "1.0.3",
     "babel-eslint": "4.1.8",
diff --git a/src/ui/public/stack_trace_mapper/set_error_stack.js b/src/ui/public/stack_trace_mapper/set_error_stack.js
deleted file mode 100644
index ff6f5b7838455..0000000000000
--- a/src/ui/public/stack_trace_mapper/set_error_stack.js
+++ /dev/null
@@ -1,34 +0,0 @@
-import _ from 'lodash';
-
-let err = new Error();
-try { setByAssignment(err, 'john'); } catch (e) {} // eslint-disable-line
-
-// err.stack is not always writeable, so we
-// do some detection for support and fallback to a
-// shadowing method, which "copies" the error but
-// keeps the original as the prototype so that
-// the error is still an instance of the same
-// classes as the original error
-if (err.stack === 'john') module.exports = setByAssignment;
-else module.exports = setByShadowing;
-
-function setByShadowing(err, stack) {
-  let props = _.mapValues(err, function (val) {
-    return {
-      enumerable: true,
-      value: val
-    };
-  });
-
-  props.stack = {
-    enumerable: true,
-    value: stack
-  };
-
-  return Object.create(err, props);
-}
-
-function setByAssignment(err, stack) {
-  err.stack = stack;
-  return err;
-}
diff --git a/src/ui/public/stack_trace_mapper/source_map_reader.js b/src/ui/public/stack_trace_mapper/source_map_reader.js
deleted file mode 100644
index 5aeb44496029b..0000000000000
--- a/src/ui/public/stack_trace_mapper/source_map_reader.js
+++ /dev/null
@@ -1,15 +0,0 @@
-import _ from 'lodash';
-import { SourceMapConsumer } from 'source-map/lib/source-map-consumer';
-import { parse } from 'url';
-
-function SourceMapReader(url, map) {
-  this.smc = new SourceMapConsumer(map);
-  this.url = parse(url);
-  this.re = new RegExp('(^|/)' + _.escapeRegExp(this.url.pathname.slice(1)) + '($|\\?|#)');
-}
-
-SourceMapReader.prototype.matchUrl = function (stackFileName) {
-  return this.re.test(stackFileName);
-};
-
-module.exports = SourceMapReader;
diff --git a/src/ui/public/stack_trace_mapper/stack_line_format.js b/src/ui/public/stack_trace_mapper/stack_line_format.js
deleted file mode 100644
index 7d4c2ebe476c7..0000000000000
--- a/src/ui/public/stack_trace_mapper/stack_line_format.js
+++ /dev/null
@@ -1,19 +0,0 @@
-import _ from 'lodash';
-
-let opts = [
-  /@((?:[!#$&-;=?-\[\]_a-z~]|%[0-9a-f]{2})+\.js)\:(\d+)(?:\:(\d+)|())/ig,
-  /(?: \(|at )((?:[!#$&-;=?-\[\]_a-z~]|%[0-9a-f]{2})+\.js)\:(\d+)(?:\:(\d+)|())/ig
-];
-
-let sample;
-try { throw new Error('msg'); } catch (e) { sample = e.stack; }
-
-let format = _.find(opts, function (format) {
-  return format.test(sample);
-});
-
-if (!format && window.console && window.console.log) {
-  window.console.log('unable to pick format with stack trace sample ' + sample);
-}
-
-module.exports = format;
diff --git a/src/ui/public/stack_trace_mapper/stack_trace_mapper.js b/src/ui/public/stack_trace_mapper/stack_trace_mapper.js
deleted file mode 100644
index 85b4366184333..0000000000000
--- a/src/ui/public/stack_trace_mapper/stack_trace_mapper.js
+++ /dev/null
@@ -1,65 +0,0 @@
-import _ from 'lodash';
-import fetch from 'exports?window.fetch!imports?Promise=bluebird!whatwg-fetch';
-
-import setErrorStack from './set_error_stack';
-import translateStackLine from './translate_stack_line';
-import stackLineFormat from './stack_line_format';
-import SourceMapReader from './source_map_reader';
-import { resolve } from 'bluebird';
-import $ from 'jquery';
-
-function StackTraceMapper() {
-  this.maps = [];
-  this.init = _.once(this.init);
-  this.getMapFor = _.memoize(this.getMapFor);
-  _.bindAll(this, 'init', 'mapError', 'getMapFor', 'mapLine', 'loadMaps');
-}
-
-StackTraceMapper.prototype.init = function (mapUrls) {
-  return this.loadMaps(mapUrls).return(this);
-};
-
-StackTraceMapper.prototype.mapError = function (err) {
-  if (!stackLineFormat || !err.stack) return err;
-
-  let stack = err.stack.replace(stackLineFormat, this.mapLine);
-  return setErrorStack(err, stack);
-};
-
-StackTraceMapper.prototype.mapLine = function (match, filename, line, col) {
-  return translateStackLine(this.getMapFor(filename), match, filename, line, col);
-};
-
-StackTraceMapper.prototype.getMapFor = function (url) {
-  return _.find(this.maps, function (map) {
-    return map.matchUrl(url);
-  });
-};
-
-StackTraceMapper.prototype.loadMaps = function (mapUrls) {
-  mapUrls = _.clone(mapUrls || {});
-
-  let maps = this.maps;
-
-  $('script[src][src-map]').each(function () {
-    let $el = $(this);
-    mapUrls[$el.attr('src')] = $el.attr('src-map');
-  });
-
-  return resolve(_.pairs(mapUrls))
-  .map(
-    _.spread(function (url, mapUrl) {
-      return fetch(mapUrl)
-      .then(function (resp) { return resp.json(); })
-      .then(function (map) {
-        maps.push(new SourceMapReader(url, map));
-      });
-    })
-  );
-};
-
-StackTraceMapper.getInstance = _.once(function () {
-  return (new StackTraceMapper()).init();
-});
-
-module.exports = StackTraceMapper;
diff --git a/src/ui/public/stack_trace_mapper/translate_stack_line.js b/src/ui/public/stack_trace_mapper/translate_stack_line.js
deleted file mode 100644
index f19f64cfe6186..0000000000000
--- a/src/ui/public/stack_trace_mapper/translate_stack_line.js
+++ /dev/null
@@ -1,41 +0,0 @@
-import _ from 'lodash';
-
-module.exports = function (map, match, filename, line, col) {
-  if (!map) return match;
-
-  let position = {
-    line: parseFloat(line) || 0,
-    column: parseFloat(col) || 0
-  };
-
-  let srcPosition = map.smc.originalPositionFor(position);
-  if (!srcPosition || !srcPosition.source) return match;
-
-  let srcFilename = srcPosition.source;
-  let srcLine = srcPosition.line;
-  let srcCol = srcPosition.column;
-
-  if (srcCol === 0 && position.column) {
-    // TODO: teach sourcemaps correct column
-    //
-    // since our bundles are not yet minified we can copy the column
-    // this won't always be the case
-    srcCol = position.column;
-  }
-
-  // fold the components into the original match, so that supporting
-  // characters (parens, periods, etc) from the format are kept, and so
-  // we don't accidentally replace the wrong part we use splitting and consumption
-  let resp = '';
-  let remainingResp = match;
-  let fold = function (replace, replacement) {
-    let wrappingContent = remainingResp.split(replace);
-    resp += wrappingContent.shift() + replacement;
-    remainingResp = wrappingContent.join(replace);
-  };
-
-  fold(filename, srcFilename);
-  fold(line, srcLine);
-  if (_.isString(col)) fold(col, srcCol);
-  return resp;
-};
diff --git a/src/ui/public/test_harness/test_harness.js b/src/ui/public/test_harness/test_harness.js
index 8d0c6cef87878..d51ff14bd250a 100644
--- a/src/ui/public/test_harness/test_harness.js
+++ b/src/ui/public/test_harness/test_harness.js
@@ -1,58 +1,23 @@
-/* global mocha */
-
 // chrome expects to be loaded first, let it get its way
 import chrome from 'ui/chrome';
 
-import Nonsense from 'Nonsense';
 import sinon from 'sinon';
-import _ from 'lodash';
 import Notifier from 'ui/notify/notifier';
-
-import StackTraceMapper from 'ui/stack_trace_mapper';
-import { parse } from 'url';
-import $ from 'jquery';
 import { setupAutoRelease } from 'auto-release-sinon';
+
 import './test_harness.less';
 import 'ng_mock';
 import { setupTestSharding } from './test_sharding';
 
-/*** the vislib tests have certain style requirements, so lets make sure they are met ***/
-$('body').attr('id', 'test-harness-body'); // so we can make high priority selectors
-
-
-/*** Setup seeded random ***/
-let seedInput = parse(window.location.href, true).query.seed;
-let seed = _.add(seedInput, 0) || Date.now();
-Math.random = _.bindKey(new Nonsense(seed), 'frac');
-Math.random.nonsense = new Nonsense(seed);
-console.log('Random-ness seed: ' + seed);
-
 // Setup auto releasing stubs and spys
 setupAutoRelease(sinon, window.afterEach);
 setupTestSharding();
 
-/*** manually map error stack traces using the sourcemap ***/
-before(function () {
-  // before the tests start, load the sourcemap and hook into error generation for the mocha reporter
-  this.timeout(30000);
+// allows test_harness.less to have higher priority selectors
+document.body.setAttribute('id', 'test-harness-body');
 
-  let mapper;
-  let Runner = window.Mocha.Runner;
-
-  Runner.prototype.emit = _.wrap(Runner.prototype.emit, function (emit, event, test, err) {
-    if (err && mapper) err = mapper.mapError(err);
-    return emit.call(this, event, test, err);
-  });
-
-  return StackTraceMapper.getInstance({
-    '/bundles/tests.bundle.js': '/bundles/tests.bundle.js.map'
-  }).then(function (instance) {
-    mapper = instance;
-  });
-});
-
-
-before(function () {
+// prevent accidental ajax requests
+before(() => {
   sinon.useFakeXMLHttpRequest();
 });
 
@@ -63,8 +28,7 @@ beforeEach(function () {
   }
 });
 
-
-/*** Kick off mocha, called at the end of test entry files ***/
-exports.bootstrap = function () {
+// Kick off mocha, called at the end of test entry files
+exports.bootstrap = () => {
   chrome.setupAngular();
 };