diff --git a/.devcontainer/requirements.txt b/.devcontainer/requirements.txt
index 6186c39..1b375ae 100644
--- a/.devcontainer/requirements.txt
+++ b/.devcontainer/requirements.txt
@@ -23,7 +23,7 @@ kiwisolver==1.4.5
 matplotlib==3.8.4
 mccabe==0.7.0
 multidict==6.0.5
-numpy==1.26.4
+numpy>=1.26.4,<2.0.0
 packaging==24.0
 pillow==10.3.0
 pycodestyle==2.11.1
diff --git a/pyproject.toml b/pyproject.toml
index 0547a1f..cfdbdd6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -33,7 +33,7 @@ requires-python = ">=3.8"
 version = "0.18.0"
 
 dependencies = [
-    "numpy >= 1.17.3",
+    "numpy >= 1.17.3, < 2.0.0",
     "requests_unixsocket",
     "pytz",
     "pyjwt",
@@ -82,4 +82,4 @@ hsstat = "h5pyd._apps.hsstat:main"
 
 [tool.setuptools]
 packages=["h5pyd", "h5pyd._hl", "h5pyd._apps"]
-include-package-data = false
\ No newline at end of file
+include-package-data = false