diff --git a/lib/do_wait_instance.js b/lib/do_wait_instance.js
index 7cb63a4..be4a7c0 100644
--- a/lib/do_wait_instance.js
+++ b/lib/do_wait_instance.js
@@ -73,11 +73,12 @@ function do_wait_instance(subcmd, opts, args, cb) {
         }
 
         uuids.forEach(function (id) {
-            var opts = {
+            var waitOpts = {
                 id: id,
                 states: states
             };
-            self.triton.cloudapi.waitForMachineStates(opts, function (err, body, res) {
+            self.triton.cloudapi.waitForMachineStates(waitOpts,
+                    function (err, body, res) {
                 if (err) {
                     cb(err);
                     return;
@@ -122,7 +123,7 @@ do_wait_instance.options = [
         helpArg: 'STATES',
         help: 'Instance states on which to wait. Default is "running,failed".'
             + 'Values can be comma-separated or multiple uses of the option.'
-    },
+    }
 ];
 
 module.exports = do_wait_instance;
diff --git a/lib/triton.js b/lib/triton.js
index 5d398b9..88ee33c 100644
--- a/lib/triton.js
+++ b/lib/triton.js
@@ -166,9 +166,9 @@ Triton.prototype.listImages = function listImages(opts, cb) {
             if (!err && self.cacheDir) {
                 // cache the results
                 var data = JSON.stringify(imgs);
-                fs.writeFile(cacheFile, data, {encoding: 'utf8'}, function (err) {
-                    if (err)
-                        self.log.info({err: err}, 'error caching images results');
+                fs.writeFile(cacheFile, data, {encoding: 'utf8'}, function (err2) {
+                    if (err2)
+                        self.log.info({err: err2}, 'error caching images results');
                     done();
                 });
             } else {
@@ -364,15 +364,15 @@ Triton.prototype.getInstance = function getInstance(name, cb) {
                 nextOnce(err);
             });
             s.on('readable', function () {
-                var inst;
-                while ((inst = s.read()) !== null) {
-                    if (inst.id.slice(0, shortId.length) === shortId) {
+                var candidate;
+                while ((candidate = s.read()) !== null) {
+                    if (candidate.id.slice(0, shortId.length) === shortId) {
                         if (match) {
                             return nextOnce(new Error(
                                 'instance short id "%s" is ambiguous',
                                 shortId));
                         } else {
-                            match = inst;
+                            match = candidate;
                         }
                     }
                 }