diff --git a/requirements.txt b/requirements.txt
index 69dc6f0..ad24e08 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,5 @@
 lark == 1.1.2
+prompt_toolkit == 3.0.30
 pycodestyle == 2.5.0
 pytest
 versioneer == 0.22
diff --git a/setup.py b/setup.py
index bd0e7ec..3d2ed43 100644
--- a/setup.py
+++ b/setup.py
@@ -28,7 +28,8 @@
         ],
     },
     install_requires=[
-        'lark == 1.1.2'
+        'lark == 1.1.2',
+        'prompt_toolkit == 3.0.30',
     ],
     classifiers=[
         "Development Status :: 3 - Alpha",
diff --git a/smallscheme/main.py b/smallscheme/main.py
index 5749aa9..1e88e18 100755
--- a/smallscheme/main.py
+++ b/smallscheme/main.py
@@ -2,7 +2,8 @@
 
 import argparse
 from smallscheme.env import Env
-from smallscheme.scheme import evalu, repl, parse_str
+from smallscheme.scheme import evalu, parse_str
+from smallscheme.repl import repl
 
 def run_file(filename):
     env = Env()
diff --git a/smallscheme/repl.py b/smallscheme/repl.py
new file mode 100644
index 0000000..828a62f
--- /dev/null
+++ b/smallscheme/repl.py
@@ -0,0 +1,30 @@
+# prompt_toolkit setup example taken from
+# https://stackoverflow.com/questions/59627995:
+from prompt_toolkit import prompt
+from prompt_toolkit import PromptSession
+from prompt_toolkit.history import FileHistory
+from os.path import expanduser
+
+from smallscheme.env import Env
+from smallscheme.scheme import parse_str, evalu, printable_value
+
+
+def repl():
+    session = PromptSession(history=FileHistory(
+        expanduser('~/.smallscheme_history')))
+
+    env = Env()
+    while True:
+        try:
+            x = session.prompt("scheme> ").strip()
+        except EOFError:
+            print()
+            break
+        if x:
+            try:
+                for parsed in parse_str(x):
+                    pv = printable_value(evalu(parsed, env))
+                    if pv:
+                        print(pv)
+            except Exception as e:
+                print(e)
diff --git a/smallscheme/scheme.py b/smallscheme/scheme.py
index 77812fe..d872228 100755
--- a/smallscheme/scheme.py
+++ b/smallscheme/scheme.py
@@ -131,26 +131,3 @@ def evalu(expr, env):
     if typeof(expr) == 'list':
         return eval_list(expr, env)
     raise Exception('evaluation error: "%s"' % str(expr))
-
-def inp():
-    if sys.version_info > (2, 9):
-        return input("scheme> ")
-    else:
-        return raw_input("scheme> ")
-
-def repl():
-    env = Env()
-    while True:
-        try:
-            x = inp().strip()
-        except EOFError:
-            print()
-            break
-        if x:
-            try:
-                for parsed in parse_str(x):
-                    pv = printable_value(evalu(parsed, env))
-                    if pv:
-                        print(pv)
-            except Exception as e:
-                print(e)