diff --git a/rpmbuild/copr-rpmbuild.spec b/rpmbuild/copr-rpmbuild.spec
index 72a4ed4d9..bd3d3ea2d 100644
--- a/rpmbuild/copr-rpmbuild.spec
+++ b/rpmbuild/copr-rpmbuild.spec
@@ -39,7 +39,6 @@ BuildRequires: %{python}-pytest
 BuildRequires: %{python_pfx}-munch
 BuildRequires: %{python}-requests
 BuildRequires: %{python_pfx}-jinja2
-BuildRequires: %{python_pfx}-simplejson
 BuildRequires: %{python_pfx}-specfile >= 0.19.0
 BuildRequires: python3-backoff >= 1.9.0
 
@@ -57,7 +56,6 @@ Requires: %{python}-copr-common >= %copr_common_version
 Requires: %{python_pfx}-jinja2
 Requires: %{python_pfx}-munch
 Requires: %{python}-requests
-Requires: %{python_pfx}-simplejson
 Requires: %{python_pfx}-specfile >= 0.19.0
 Requires: python3-backoff >= 1.9.0
 
diff --git a/rpmbuild/copr_rpmbuild/automation/rpm_results.py b/rpmbuild/copr_rpmbuild/automation/rpm_results.py
index 77d7d7a89..60f26f059 100644
--- a/rpmbuild/copr_rpmbuild/automation/rpm_results.py
+++ b/rpmbuild/copr_rpmbuild/automation/rpm_results.py
@@ -2,8 +2,9 @@
 Create `results.json` file
 """
 
+import json
 import os
-import simplejson
+
 from copr_rpmbuild.automation.base import AutomationTool
 from copr_rpmbuild.helpers import get_rpm_header
 
@@ -28,7 +29,7 @@ def run(self):
         packages = {"packages": nevras}
         path = os.path.join(self.resultdir, "results.json")
         with open(path, "w") as dst:
-            simplejson.dump(packages, dst, indent=4)
+            json.dump(packages, dst, indent=4)
 
     def find_results_nevras_dicts(self):
         """
diff --git a/rpmbuild/copr_rpmbuild/automation/srpm_results.py b/rpmbuild/copr_rpmbuild/automation/srpm_results.py
index be4d75741..2618008b8 100644
--- a/rpmbuild/copr_rpmbuild/automation/srpm_results.py
+++ b/rpmbuild/copr_rpmbuild/automation/srpm_results.py
@@ -2,8 +2,9 @@
 Create `results.json` file for SRPM builds
 """
 
+import json
 import os
-import simplejson
+
 from copr_rpmbuild.automation.base import AutomationTool
 from copr_rpmbuild.helpers import (
     get_rpm_header,
@@ -32,7 +33,7 @@ def run(self):
         data = self.get_package_info()
         path = os.path.join(self.resultdir, "results.json")
         with open(path, "w", encoding="utf-8") as dst:
-            simplejson.dump(data, dst, indent=4)
+            json.dump(data, dst, indent=4)
 
     def get_package_info(self):
         """
diff --git a/rpmbuild/main.py b/rpmbuild/main.py
index 84c90c90c..ad8749dea 100755
--- a/rpmbuild/main.py
+++ b/rpmbuild/main.py
@@ -13,11 +13,6 @@
 import shlex
 import pkg_resources
 
-try:
-    from simplejson.scanner import JSONDecodeError
-except ImportError:
-    JSONDecodeError = Exception
-
 from copr_common.request import SafeRequest, RequestError
 from copr_rpmbuild import providers
 from copr_rpmbuild.builders.mock import MockBuilder
@@ -320,8 +315,8 @@ def get_vanilla_build_config(url):
             raise RuntimeError("No valid build_config at {0}".format(url))
         return build_config
 
-    except JSONDecodeError:
-        raise RuntimeError("No valid build_config at {0}".format(url))
+    except json.decoder.JSONDecodeError as ex:
+        raise RuntimeError("No valid build_config at {0}".format(url)) from ex
 
 
 def read_task_from_file(path):
@@ -330,8 +325,8 @@ def read_task_from_file(path):
             return json.loads(f.read())
     except OSError as ex:
         raise RuntimeError(ex)
-    except json.decoder.JSONDecodeError:
-        raise RuntimeError("No valid build_config at {0}".format(path))
+    except json.decoder.JSONDecodeError as ex:
+        raise RuntimeError("No valid build_config at {0}".format(path)) from ex
 
 
 if __name__ == "__main__":