diff --git a/joy/__main__.py b/joy/__main__.py
index a6c682b..c461ef8 100644
--- a/joy/__main__.py
+++ b/joy/__main__.py
@@ -17,15 +17,16 @@
 #    You should have received a copy of the GNU General Public License
 #    along with Thun.  If not see <http://www.gnu.org/licenses/>.
 #
+from __future__ import print_function
 from .library import initialize
 from .joy import repl
 
-print '''\
+print('''\
 Thun - Copyright © 2017 Simon Forman
 This program comes with ABSOLUTELY NO WARRANTY; for details type "warranty".
 This is free software, and you are welcome to redistribute it
 under certain conditions; type "sharing" for details.
 Type "words" to see a list of all words, and "[<name>] help" to print the
 docs for a word.
-'''
+''')
 stack = repl(dictionary=initialize())
diff --git a/joy/library.py b/joy/library.py
index 2e57aad..eb44529 100644
--- a/joy/library.py
+++ b/joy/library.py
@@ -23,6 +23,7 @@ functions.  Its main export is a Python function initialize() that
 returns a dictionary of Joy functions suitable for use with the joy()
 function.
 '''
+from __future__ import print_function
 from logging import getLogger
 
 _log = getLogger(__name__)
diff --git a/joy/utils/compiler.py b/joy/utils/compiler.py
index 7e72c4c..45ed27a 100644
--- a/joy/utils/compiler.py
+++ b/joy/utils/compiler.py
@@ -10,9 +10,11 @@ functions, during inference?  Could I write out better code that way?
 
 In any event, I am proceeding with this sort of ad hoc way for now.
 '''
+from __future__ import print_function
 from joy.parser import text_to_expression, Symbol
 from joy.utils.stack import concat, iter_stack, list_to_stack
 from joy.library import SimpleFunctionWrapper, YIN_STACK_EFFECTS
+from functools import reduce
 
 
 def import_yin():
@@ -29,7 +31,7 @@ class InfiniteStack(tuple):
             n = n + 1 if m is None else m
 
     _NAMES = _names()
-    _NAMES.next()
+    next(_NAMES)
 
     names = _NAMES.next
     reset = lambda _, _n=_NAMES: _n.send(-1)
@@ -82,7 +84,7 @@ def code_gen(code):
 
 def coalesce_pops(code):
     code.sort(key=lambda p: p[0] != 'pop')  # All pops to the front.
-    try: index = (i for i, t in enumerate(code) if t[0] != 'pop').next()
+    try: index = next((i for i, t in enumerate(code) if t[0] != 'pop'))
     except StopIteration: return
     code[:index] = [tuple(['pop'] + [t for _, t in code[:index][::-1]])]
 
@@ -216,21 +218,21 @@ for name in '''
 '''
 
 for name in sorted(D):
-    print name,
+    print(name, end=' ')
 ##    print compile_yinyang(name, name)
-print '-' * 100
+print('-' * 100)
 
 
-print compile_yinyang('mul_', 'mul')
-print compile_yinyang('pop', 'pop')
-print compile_yinyang('ppm', 'popop mul')
-print compile_yinyang('sqr', 'dup mul')
-print compile_yinyang('foo', 'dup 23 sub mul')
-print compile_yinyang('four_mul', 'mul mul mul mul')
-print compile_yinyang('baz', 'mul dup sub dup')
-print compile_yinyang('to_the_fifth_power', 'dup dup mul dup mul mul')
-print compile_yinyang('dup3', 'dup dup dup')
-print compile_yinyang('df2m', 'dup first_two mul')
-print compile_yinyang('sqr_first', 'uncons swap dup mul swons')
-print compile_yinyang('0BAD',      'uncons      dup mul')
-print compile_yinyang('uncons', 'uncons')
+print(compile_yinyang('mul_', 'mul'))
+print(compile_yinyang('pop', 'pop'))
+print(compile_yinyang('ppm', 'popop mul'))
+print(compile_yinyang('sqr', 'dup mul'))
+print(compile_yinyang('foo', 'dup 23 sub mul'))
+print(compile_yinyang('four_mul', 'mul mul mul mul'))
+print(compile_yinyang('baz', 'mul dup sub dup'))
+print(compile_yinyang('to_the_fifth_power', 'dup dup mul dup mul mul'))
+print(compile_yinyang('dup3', 'dup dup dup'))
+print(compile_yinyang('df2m', 'dup first_two mul'))
+print(compile_yinyang('sqr_first', 'uncons swap dup mul swons'))
+print(compile_yinyang('0BAD',      'uncons      dup mul'))
+print(compile_yinyang('uncons', 'uncons'))
diff --git a/joy/utils/types.py b/joy/utils/types.py
index 7c0ce83..8da4c6a 100644
--- a/joy/utils/types.py
+++ b/joy/utils/types.py
@@ -17,7 +17,9 @@
 #    You should have received a copy of the GNU General Public License
 #    along with Thun.  If not see <http://www.gnu.org/licenses/>. 
 #
+from __future__ import print_function
 from logging import getLogger, addLevelName
+from functools import reduce
 
 _log = getLogger(__name__)
 addLevelName(15, 'hmm')
@@ -721,20 +723,20 @@ def combinator_effect(number, *expect):
 def show(DEFS):
   for name, stack_effect_comment in sorted(DEFS.iteritems()):
     t = ' *'[compilable(stack_effect_comment)]
-    print name, '=', doc_from_stack_effect(*stack_effect_comment), t
+    print(name, '=', doc_from_stack_effect(*stack_effect_comment), t)
 
 
 def generate_library_code(DEFS, f=None):
   if f is None:
     import sys
     f = sys.stdout
-  print >> f, '# GENERATED FILE. DO NOT EDIT.\n'
+  print('# GENERATED FILE. DO NOT EDIT.\n', file=f)
   for name, stack_effect_comment in sorted(DEFS.iteritems()):
     if not compilable(stack_effect_comment):
       continue
-    print >> f
-    print >> f, compile_(name, stack_effect_comment)
-    print >> f
+    print(file=f)
+    print(compile_(name, stack_effect_comment), file=f)
+    print(file=f)
 
 
 def poly_combinator_effect(number, effect_funcs, *expect):