diff --git a/extras/jsl.conf b/extras/jsl.conf
new file mode 100644
index 00000000..a1ae872d
--- /dev/null
+++ b/extras/jsl.conf
@@ -0,0 +1,44 @@
+# JavaScriptLint configuration file for CoffeeScript.
+
++no_return_value              # function {0} does not always return a value
++duplicate_formal             # duplicate formal argument {0}
++equal_as_assign              # test for equality (==) mistyped as assignment (=)?{0}
++var_hides_arg                # variable {0} hides argument
++redeclared_var               # redeclaration of {0} {1}
++anon_no_return_value         # anonymous function does not always return a value
++missing_semicolon            # missing semicolon
++meaningless_block            # meaningless block; curly braces have no impact
++comma_separated_stmts        # multiple statements separated by commas (use semicolons?)
++unreachable_code             # unreachable code
++missing_break                # missing break statement
++missing_break_for_last_case  # missing break statement for last case in switch
+-comparison_type_conv         # comparisons against null, 0, true, false, or an empty string allowing implicit type conversion (use === or !==)
++inc_dec_within_stmt          # increment (++) and decrement (--) operators used as part of greater statement
++useless_void                 # use of the void type may be unnecessary (void is always undefined)
++multiple_plus_minus          # unknown order of operations for successive plus (e.g. x+++y) or minus (e.g. x---y) signs
++use_of_label                 # use of label
+-block_without_braces         # block statement without curly braces
++leading_decimal_point        # leading decimal point may indicate a number or an object member
++trailing_decimal_point       # trailing decimal point may indicate a number or an object member
++octal_number                 # leading zeros make an octal number
++nested_comment               # nested comment
++misplaced_regex              # regular expressions should be preceded by a left parenthesis, assignment, colon, or comma
++ambiguous_newline            # unexpected end of line; it is ambiguous whether these lines are part of the same statement
++empty_statement              # empty statement or extra semicolon
+-missing_option_explicit      # the "option explicit" control comment is missing
++partial_option_explicit      # the "option explicit" control comment, if used, must be in the first script tag
++dup_option_explicit          # duplicate "option explicit" control comment
++useless_assign               # useless assignment
++ambiguous_nested_stmt        # block statements containing block statements should use curly braces to resolve ambiguity
++ambiguous_else_stmt          # the else statement could be matched with one of multiple if statements (use curly braces to indicate intent)
++missing_default_case         # missing default case in switch statement
++duplicate_case_in_switch     # duplicate case in switch statements
++default_not_at_end           # the default case is not at the end of the switch statement
++legacy_cc_not_understood     # couldn't understand control comment using /*@keyword@*/ syntax
++jsl_cc_not_understood        # couldn't understand control comment using /*jsl:keyword*/ syntax
++useless_comparison           # useless comparison; comparing identical expressions
++with_statement               # with statement hides undeclared variables; use temporary variable instead
++trailing_comma_in_array      # extra comma is not recommended in array initializers
++assign_to_function_call      # assignment to a function call
++parseint_missing_radix       # parseInt missing radix parameter
++lambda_assign_requires_semicolon
diff --git a/lib/command.js b/lib/command.js
index 7b081da5..df7311ca 100644
--- a/lib/command.js
+++ b/lib/command.js
@@ -188,11 +188,12 @@
     });
   };
   lint = function(js) {
-    var jsl, printIt;
+    var conf, jsl, printIt;
     printIt = function(buffer) {
-      return print(buffer.toString());
+      return puts(buffer.toString().trim());
     };
-    jsl = spawn('jsl', ['-nologo', '-stdin']);
+    conf = __dirname + '/../extras/jsl.conf';
+    jsl = spawn('jsl', ['-nologo', '-stdin', '-conf', conf]);
     jsl.stdout.on('data', printIt);
     jsl.stderr.on('data', printIt);
     jsl.stdin.write(js);
diff --git a/lib/nodes.js b/lib/nodes.js
index 24f81ee2..2e95793d 100644
--- a/lib/nodes.js
+++ b/lib/nodes.js
@@ -402,7 +402,7 @@
               temp = o.scope.freeVariable();
               complete = ("(" + (baseline = temp) + " = (" + (complete) + "))");
             }
-            complete = i === 0 ? ("(typeof " + (complete) + " === \"undefined\" || " + (baseline) + " === null) ? undefined : ") : ("" + (complete) + " == undefined ? undefined : ");
+            complete = i === 0 ? ("(typeof " + (complete) + " === \"undefined\" || " + (baseline) + " === null) ? undefined : ") : ("" + (complete) + " == null ? undefined : ");
             return complete += (baseline += prop.compile(o));
           } else {
             part = prop.compile(o);
@@ -1643,10 +1643,10 @@
       return true;
     };
     IfNode.prototype.bodyNode = function() {
-      return this.body == undefined ? undefined : this.body.unwrap();
+      return this.body == null ? undefined : this.body.unwrap();
     };
     IfNode.prototype.elseBodyNode = function() {
-      return this.elseBody == undefined ? undefined : this.elseBody.unwrap();
+      return this.elseBody == null ? undefined : this.elseBody.unwrap();
     };
     IfNode.prototype.forceStatement = function() {
       this.tags.statement = true;
diff --git a/lib/rewriter.js b/lib/rewriter.js
index 5412d6ef..c228c82a 100644
--- a/lib/rewriter.js
+++ b/lib/rewriter.js
@@ -328,7 +328,7 @@
             }
             debt[mtag] += 1;
             val = [oppos, mtag === 'INDENT' ? match[1] : oppos];
-            if ((this.tokens[i + 2] == undefined ? undefined : this.tokens[i + 2][0]) === mtag) {
+            if ((this.tokens[i + 2] == null ? undefined : this.tokens[i + 2][0]) === mtag) {
               this.tokens.splice(i + 3, 0, val);
               stack.push(match);
             } else {
diff --git a/src/command.coffee b/src/command.coffee
index 2b2acaee..0ec180cf 100644
--- a/src/command.coffee
+++ b/src/command.coffee
@@ -153,8 +153,9 @@ writeJs = (source, js, base) ->
 # Pipe compiled JS through JSLint (requires a working `jsl` command), printing
 # any errors or warnings that arise.
 lint = (js) ->
-  printIt = (buffer) -> print buffer.toString()
-  jsl = spawn 'jsl', ['-nologo', '-stdin']
+  printIt = (buffer) -> puts buffer.toString().trim()
+  conf = __dirname + '/../extras/jsl.conf'
+  jsl = spawn 'jsl', ['-nologo', '-stdin', '-conf', conf]
   jsl.stdout.on 'data', printIt
   jsl.stderr.on 'data', printIt
   jsl.stdin.write js
diff --git a/src/nodes.coffee b/src/nodes.coffee
index 8bef9985..5e78d739 100644
--- a/src/nodes.coffee
+++ b/src/nodes.coffee
@@ -367,7 +367,7 @@ exports.ValueNode = class ValueNode extends BaseNode
         complete = if i is 0
           "(typeof #{complete} === \"undefined\" || #{baseline} === null) ? undefined : "
         else
-          "#{complete} == undefined ? undefined : "
+          "#{complete} == null ? undefined : "
         complete += (baseline += prop.compile(o))
       else
         part = prop.compile(o)