diff --git a/src/helpers/util.js b/src/helpers/util.js
index 143dbace90..408523cbd2 100644
--- a/src/helpers/util.js
+++ b/src/helpers/util.js
@@ -44,34 +44,31 @@ module.exports = {
   /*
     Binary Search:
     Assumes that @arg array is sorted increasingly
-    returns the smallest i such that target >= changes[i]
-    returns arary.length - 1 (if all elements in array are smaller than target)
-    returns 0 (if target is smaller than the first element of array || if array is empty)
+    return smallest i such that changes[i] <= target does not hold,
+    or changes.length if all elements are < target.
+    It returns the index where target could be inserted to maintain the order of the array
   */
   findLowerBound: function (target, array) {
-    if (array.length === 0) {
-      return 0
-    }
-    return findLowerBoundInternal(target, array, 0, array.length - 1)
+    return findLowerBoundInternal(target, array, 0, array.length)
+  },
+
+  findLowerBoundValue: function (target, array) {
+    var index = this.findLowerBound(target, array)
+    return array[index]
   }
 }
 
-function findLowerBoundInternal (target, array, lowerbound, higherbound) {
-  if (array[higherbound] < target) {
-    return higherbound
-  } else if (array[lowerbound] > target) {
-    return lowerbound
-  }
-  var middle
-  while (lowerbound + 1 !== higherbound) {
-    middle = Math.floor((higherbound + lowerbound) / 2)
-    if (array[middle] > target) {
-      higherbound = middle
-    } else if (array[middle] < target) {
+function findLowerBoundInternal (target, array, lowerbound, length) {
+  while (length > 1) {
+    var half = length >> 1
+    var middle = lowerbound + half
+    if (array[middle] < target) {
+      length = length - (middle - lowerbound)
       lowerbound = middle
-      higherbound = array.length - 1
     } else if (array[middle] === target) {
       return middle
+    } else {
+      length = half
     }
   }
   return lowerbound
diff --git a/src/index.js b/src/index.js
index 6a17480e35..2325fe9d97 100644
--- a/src/index.js
+++ b/src/index.js
@@ -9,9 +9,6 @@ var SourceMappingDecoder = require('./util/sourceMappingDecoder')
 if (typeof (module) !== 'undefined' && typeof (module.exports) !== 'undefined') {
   module.exports = modules()
 }
-if (typeof (window) !== 'undefined') {
-  window.remix = modules()
-}
 
 function modules () {
   return {
diff --git a/src/trace/traceManager.js b/src/trace/traceManager.js
index 4347ef3c27..0440808b55 100644
--- a/src/trace/traceManager.js
+++ b/src/trace/traceManager.js
@@ -80,8 +80,7 @@ TraceManager.prototype.getStorageAt = function (stepIndex, tx, callback, address
     return callback(check, null)
   }
   if (!address) {
-    var stoChangeIndex = util.findLowerBound(stepIndex, this.traceCache.storageChanges)
-    var stoChange = this.traceCache.storageChanges[stoChangeIndex]
+    var stoChange = util.findLowerBoundValue(stepIndex, this.traceCache.storageChanges)
     if (stoChange === undefined) return callback('no storage found', null)
     address = this.traceCache.sstore[stoChange].address
   }
@@ -124,8 +123,7 @@ TraceManager.prototype.getCallDataAt = function (stepIndex, callback) {
   if (check) {
     return callback(check, null)
   }
-  var callDataChangeIndex = util.findLowerBound(stepIndex, this.traceCache.callDataChanges)
-  var callDataChange = this.traceCache.callDataChanges[callDataChangeIndex]
+  var callDataChange = util.findLowerBoundValue(stepIndex, this.traceCache.callDataChanges)
   if (callDataChange === undefined) return callback('no calldata found', null)
   callback(null, [this.traceCache.callsData[callDataChange]])
 }
@@ -135,8 +133,7 @@ TraceManager.prototype.getCallStackAt = function (stepIndex, callback) {
   if (check) {
     return callback(check, null)
   }
-  var callStackChangeIndex = util.findLowerBound(stepIndex, this.traceCache.callChanges)
-  var callStackChange = this.traceCache.callChanges[callStackChangeIndex]
+  var callStackChange = util.findLowerBoundValue(stepIndex, this.traceCache.callChanges)
   if (callStackChange === undefined) return callback('no callstack found', null)
   callback(null, this.traceCache.callStack[callStackChange].callStack)
 }
@@ -161,8 +158,7 @@ TraceManager.prototype.getLastCallChangeSince = function (stepIndex, callback) {
   if (check) {
     return callback(check, null)
   }
-  var callChangeIndex = util.findLowerBound(stepIndex, this.traceCache.callChanges)
-  var callChange = this.traceCache.callChanges[callChangeIndex]
+  var callChange = util.findLowerBoundValue(stepIndex, this.traceCache.callChanges)
   if (callChange === undefined) {
     callback(null, 0)
   } else {
@@ -208,8 +204,7 @@ TraceManager.prototype.getMemoryAt = function (stepIndex, callback) {
   if (check) {
     return callback(check, null)
   }
-  var lastChangesIndex = util.findLowerBound(stepIndex, this.traceCache.memoryChanges)
-  var lastChanges = this.traceCache.memoryChanges[lastChangesIndex]
+  var lastChanges = util.findLowerBoundValue(stepIndex, this.traceCache.memoryChanges)
   if (lastChanges === undefined) return callback('no memory found', null)
   callback(null, this.trace[lastChanges].memory)
 }
diff --git a/src/util/sourceMappingDecoder.js b/src/util/sourceMappingDecoder.js
index 697a1e47fa..188bde0a93 100644
--- a/src/util/sourceMappingDecoder.js
+++ b/src/util/sourceMappingDecoder.js
@@ -77,15 +77,6 @@ SourceMappingDecoder.prototype.getLinebreakPositions = function (source) {
     ret.push(pos)
   }
   return ret
-    /*
-  var lines = source.split('\n')
-  var currentPos = 0
-  var ret = []
-  for (var k in lines) {
-    ret.push(currentPos + lines[k].length)
-    currentPos += lines[k].length + 1
-  }
-  return ret*/
 }
 
 /**
@@ -93,7 +84,7 @@ SourceMappingDecoder.prototype.getLinebreakPositions = function (source) {
  *
  * @param {Object} sourceLocation - object containing attributes {source} and {length}
  * @param {Array} lineBreakPositions - array returned by the function 'getLinebreakPositions'
- * @@return {Object} returns an object {start: {line, column}, end: {line, column}}
+ * @@return {Object} returns an object {start: {line, column}, end: {line, column}} (line count start at 0)
  */
 SourceMappingDecoder.prototype.convertOffsetToLineColumn = function (sourceLocation, lineBreakPositions) {
   if (sourceLocation.start >= 0 && sourceLocation.length >= 0) {
@@ -109,22 +100,15 @@ SourceMappingDecoder.prototype.convertOffsetToLineColumn = function (sourceLocat
   }
 }
 
-function convertFromCharPosition (pos, lineColumnLayout) {
-  var lowerBound = util.findLowerBound(pos, lineColumnLayout)
-  var line
-  if (lowerBound === 0) {
-    line = 0
-  } else if (lowerBound < pos) {
-    line = lowerBound + 1
-  } else {
-    line = lowerBound
-  }
-  var column
-  if (lowerBound === 0) {
-    column = pos
-  } else {
-    column = pos - 1 - lineColumnLayout[line - 1]
+function convertFromCharPosition (pos, lineBreakPositions) {
+  var line = util.findLowerBound(pos, lineBreakPositions)
+
+  if (lineBreakPositions[line] < pos) {
+    line = line + 1
   }
+
+  var column = lineBreakPositions[line - 1] ? (pos - lineBreakPositions[line - 1] - 1) : pos
+
   return {
     line: line,
     column: column