diff --git a/pyproject.toml b/pyproject.toml
index c5b0168..cdcad6b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,7 +21,7 @@ dependencies = [
     "scipy >=1.4.1",
     "SoundFile >=0.10.3",
 ]
-version = "4.0.0.post2"
+version = "5.0.0rc1"
 readme = "README.md"
 license = {file = "LICENSE"}
 classifiers = [
diff --git a/src/crowsetta/__about__.py b/src/crowsetta/__about__.py
index e7d8589..5b33654 100644
--- a/src/crowsetta/__about__.py
+++ b/src/crowsetta/__about__.py
@@ -23,7 +23,7 @@
 __summary__ = "A Python tool to work with any format for annotating animal vocalizations and bioacoustics data"
 __uri__ = "https://github.com/vocalpy/crowsetta"
 
-__version__ = "4.0.0.post2"
+__version__ = "5.0.0rc1"
 
 if base_dir is not None and os.path.exists(os.path.join(base_dir, ".commit")):
     with open(os.path.join(base_dir, ".commit")) as fp: