diff --git a/CHANGELOG.md b/CHANGELOG.md
index 986a2aa0..dbeba3e1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Changed
+
+Update pip_freeze to use `pip freeze` since Connect filters for valid package paths in the backend and it no longer depends on the undocumented behavior of `pip list --format=freeze`. This reverts the change made in 1.5.2.
+
 ## [1.12.1] - 2022-11-07
 
 ### Changed
diff --git a/rsconnect/environment.py b/rsconnect/environment.py
index a2851b3b..337bec89 100644
--- a/rsconnect/environment.py
+++ b/rsconnect/environment.py
@@ -43,15 +43,15 @@
 
 
 def MakeEnvironment(
-    conda=None,  # type: Optional[str]
-    contents="",  # type: Optional[str]
-    error=None,  # type: Optional[str]
-    filename="",  # type: Optional[str]
-    locale="",  # type: Optional[str]
-    package_manager="",  # type: Optional[str]
-    pip=None,  # type: Optional[str]
-    python=None,  # type: Optional[str]
-    source=None,  # type: Optional[str]
+    conda: Optional[str] = None,
+    contents: Optional[str] = None,
+    error: Optional[str] = None,
+    filename: Optional[str] = None,
+    locale: Optional[str] = None,
+    package_manager: Optional[str] = None,
+    pip: Optional[str] = None,
+    python: Optional[str] = None,
+    source: Optional[str] = None,
 ):
     return Environment(conda, contents, error, filename, locale, package_manager, pip, python, source)
 
@@ -218,7 +218,7 @@ def pip_freeze():
     """
     try:
         proc = subprocess.Popen(
-            [sys.executable, "-m", "pip", "list", "--format=freeze"],
+            [sys.executable, "-m", "pip", "freeze"],
             stdout=subprocess.PIPE,
             stderr=subprocess.PIPE,
             universal_newlines=True,