diff --git a/dissect/esedb/c_esedb.py b/dissect/esedb/c_esedb.py
index 8bc95bb..13b1ffc 100644
--- a/dissect/esedb/c_esedb.py
+++ b/dissect/esedb/c_esedb.py
@@ -4,10 +4,10 @@
 from collections import namedtuple
 from typing import Union
 
-from dissect import cstruct
+from dissect.cstruct import cstruct
 
 # https://github.com/microsoft/Extensible-Storage-Engine
-c_esedb_def = """
+esedb_def = """
 #define MAX_COMPUTERNAME_LENGTH 15
 
 typedef int64 DBTIME;
@@ -427,8 +427,7 @@
 };
 """  # noqa E501
 
-c_esedb = cstruct.cstruct()
-c_esedb.load(c_esedb_def)
+c_esedb = cstruct().load(esedb_def)
 
 ulDAEMagic = 0x89ABCDEF
 pgnoFDPMSO = 4
diff --git a/pyproject.toml b/pyproject.toml
index 9b535ea..acb7eb2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,8 +25,8 @@ classifiers = [
   "Topic :: Utilities",
 ]
 dependencies = [
-    "dissect.cstruct>=3.4.dev,<4.0.dev",
-    "dissect.util>=3.5.dev,<4.0.dev",
+    "dissect.cstruct>=4.dev,<5",
+    "dissect.util>=3.5,<4",
 ]
 dynamic = ["version"]
 
@@ -35,6 +35,12 @@ homepage = "https://dissect.tools"
 documentation = "https://docs.dissect.tools/en/latest/projects/dissect.esedb"
 repository = "https://github.com/fox-it/dissect.esedb"
 
+[project.optional-dependencies]
+dev = [
+    "dissect.cstruct>=4.0.dev,<5.0.dev",
+    "dissect.util>=3.5.dev,<4.0.dev",
+]
+
 [tool.black]
 line-length = 120
 
diff --git a/tox.ini b/tox.ini
index 67e8e8a..7bd2890 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,6 +11,7 @@ minversion = 4.4.3
 requires = virtualenv>=20.16.6
 
 [testenv]
+extras = dev
 deps =
     pytest
     pytest-cov