diff --git a/luigi/s3.py b/luigi/s3.py
index 17cedc5682..b0dbfa3787 100644
--- a/luigi/s3.py
+++ b/luigi/s3.py
@@ -17,11 +17,9 @@
 import os.path
 import random
 import tempfile
+import warnings
 import urlparse
 
-import boto
-from boto.s3.key import Key
-
 import configuration
 from ConfigParser import NoSectionError, NoOptionError
 from luigi.parameter import Parameter
@@ -31,12 +29,20 @@
 from luigi.task import ExternalTask
 from luigi.format import FileWrapper
 
+logger = logging.getLogger('luigi-interface')
+
+try:
+    import boto
+    from boto.s3.key import Key
+except ImportError:
+    logger.warning("Loading s3 module without boto installed. Will crash at runtime if s3 functionality is used.")
+
+
 # two different ways of marking a directory
 # with a suffix in S3
 S3_DIRECTORY_MARKER_SUFFIX_0 = '_$folder$'
 S3_DIRECTORY_MARKER_SUFFIX_1 = '/'
 
-logger = logging.getLogger('luigi-interface')
 
 class InvalidDeleteException(FileSystemException):
     pass
diff --git a/luigi/webhdfs.py b/luigi/webhdfs.py
index 36b04d8b05..96c8d15b73 100644
--- a/luigi/webhdfs.py
+++ b/luigi/webhdfs.py
@@ -5,10 +5,18 @@
 """
 import datetime
 import configuration
+import logging
 import os
 import posixpath
 import urlparse
-import whoops
+
+logger = logging.getLogger("luigi-interface")
+
+try:
+    import whoops
+except ImportError:
+    logger.warning("Loading webhdfs module without whoops installed. Will crash at runtime if webhdfs functionality is used.")
+
 
 
 def get_whoops_defaults(config=None):
@@ -60,10 +68,6 @@ class WebHdfsClient(object):
     use the client, you must specify `namenode_host` and `namenode_port` in the `hdfs` section of
     your luigi configuration."""
 
-    def __init__(self):
-        "Configures _homedir so that we can handle relative paths"
-        self._homedir = get_whoops("/").home()
-
     def _make_absolute(self, inpath):
         """Makes the given path absolute if it's not already. It is assumed that the path is
         relative to self._homedir"""
@@ -72,7 +76,7 @@ def _make_absolute(self, inpath):
         if scheme or posixpath.isabs(path):
             # if a scheme is specified, assume it's absolute.
             return path
-        return posixpath.join(self._homedir, path)
+        return posixpath.join(get_whoops("/").home(), path)
 
     def exists(self, path):
         """Returns true if the path exists and false otherwise"""