diff --git a/pkgs/development/python-modules/flask-bootstrap/default.nix b/pkgs/development/python-modules/flask-bootstrap/default.nix
index 797be78bc563..3088e7392a48 100644
--- a/pkgs/development/python-modules/flask-bootstrap/default.nix
+++ b/pkgs/development/python-modules/flask-bootstrap/default.nix
@@ -1,11 +1,12 @@
 { lib, buildPythonPackage, fetchPypi, flask, visitor, dominate }:
 
 buildPythonPackage rec {
-  pname = "Flask-Bootstrap";
+  pname = "flask-bootstrap";
   version = "3.3.7.1";
 
   src = fetchPypi {
-    inherit pname version;
+    pname = "Flask-Bootstrap";
+    inherit version;
     sha256 = "1j1s2bplaifsnmr8vfxa3czca4rz78xyhrg4chx39xl306afs26b";
   };
 
diff --git a/pkgs/development/python-modules/flask-caching/default.nix b/pkgs/development/python-modules/flask-caching/default.nix
index e9b1e3643bdb..7ac2830bcf18 100644
--- a/pkgs/development/python-modules/flask-caching/default.nix
+++ b/pkgs/development/python-modules/flask-caching/default.nix
@@ -12,13 +12,14 @@
 }:
 
 buildPythonPackage rec {
-  pname = "Flask-Caching";
+  pname = "flask-caching";
   version = "2.1.0";
   format = "setuptools";
   disabled = pythonOlder "3.7";
 
   src = fetchPypi {
-    inherit pname version;
+    pname = "Flask-Caching";
+    inherit version;
     hash = "sha256-t1AMFFE1g2qVLj3jqAiB2WVOMnopyFLJJlYH9cRJI1w=";
   };
 
diff --git a/pkgs/development/python-modules/flask-common/default.nix b/pkgs/development/python-modules/flask-common/default.nix
index cba8e9e8efd4..54c8ef95e5a0 100644
--- a/pkgs/development/python-modules/flask-common/default.nix
+++ b/pkgs/development/python-modules/flask-common/default.nix
@@ -2,11 +2,12 @@
 , crayons, flask, flask-caching, gunicorn, maya, meinheld, whitenoise }:
 
 buildPythonPackage rec {
-  pname = "Flask-Common";
+  pname = "flask-common";
   version = "0.3.0";
 
   src = fetchPypi {
-    inherit pname version;
+    pname = "Flask-Common";
+    inherit version;
     sha256 = "13d99f2dbc0a332b8bc4b2cc394d3e48f89672c266868e372cd9d7b433d921a9";
   };
 
diff --git a/pkgs/development/python-modules/flask-seasurf/default.nix b/pkgs/development/python-modules/flask-seasurf/default.nix
index 26dd2d7f5e08..1764e2762059 100644
--- a/pkgs/development/python-modules/flask-seasurf/default.nix
+++ b/pkgs/development/python-modules/flask-seasurf/default.nix
@@ -1,7 +1,7 @@
 { lib, fetchFromGitHub, fetchpatch, buildPythonPackage, isPy3k, flask, mock, unittestCheckHook }:
 
 buildPythonPackage rec {
-  pname = "Flask-SeaSurf";
+  pname = "flask-seasurf";
   version = "1.1.1";
   disabled = !isPy3k;
 
diff --git a/pkgs/development/python-modules/flask-session/default.nix b/pkgs/development/python-modules/flask-session/default.nix
index a777bf0920ab..e3c4abf8da8a 100644
--- a/pkgs/development/python-modules/flask-session/default.nix
+++ b/pkgs/development/python-modules/flask-session/default.nix
@@ -8,7 +8,7 @@
 }:
 
 buildPythonPackage rec {
-  pname = "Flask-Session";
+  pname = "flask-session";
   version = "0.5.0";
   format = "pyproject";
 
diff --git a/pkgs/development/python-modules/flask-silk/default.nix b/pkgs/development/python-modules/flask-silk/default.nix
index 8a40b6d4b56f..ddee5077970d 100644
--- a/pkgs/development/python-modules/flask-silk/default.nix
+++ b/pkgs/development/python-modules/flask-silk/default.nix
@@ -5,7 +5,7 @@
 }:
 
 buildPythonPackage {
-  pname = "Flask-Silk";
+  pname = "flask-silk";
   version = "unstable-2018-06-28";
 
   # master fixes flask import syntax and has no major changes
diff --git a/pkgs/development/python-modules/flask-socketio/default.nix b/pkgs/development/python-modules/flask-socketio/default.nix
index 53a793c75f5a..7460bf2309d4 100644
--- a/pkgs/development/python-modules/flask-socketio/default.nix
+++ b/pkgs/development/python-modules/flask-socketio/default.nix
@@ -10,7 +10,7 @@
 }:
 
 buildPythonPackage rec {
-  pname = "Flask-SocketIO";
+  pname = "flask-socketio";
   version = "5.3.6";
   format = "pyproject";
 
diff --git a/pkgs/development/python-modules/flask-sslify/default.nix b/pkgs/development/python-modules/flask-sslify/default.nix
index ad4bc4dc0523..bb3ef6c8cd1a 100644
--- a/pkgs/development/python-modules/flask-sslify/default.nix
+++ b/pkgs/development/python-modules/flask-sslify/default.nix
@@ -1,11 +1,12 @@
 { lib, fetchPypi, buildPythonPackage, flask }:
 
 buildPythonPackage rec {
-  pname = "Flask-SSLify";
+  pname = "flask-sslify";
   version = "0.1.5";
 
   src = fetchPypi {
-    inherit pname version;
+    pname = "Flask-SSLify";
+    inherit version;
     sha256 = "0gjl1m828z5dm3c5dpc2qjgi4llf84cp72mafr0ib5fd14y1sgnk";
   };
 
diff --git a/pkgs/development/python-modules/flask-versioned/default.nix b/pkgs/development/python-modules/flask-versioned/default.nix
index fd915fdc18f3..1d54e49e417d 100644
--- a/pkgs/development/python-modules/flask-versioned/default.nix
+++ b/pkgs/development/python-modules/flask-versioned/default.nix
@@ -1,7 +1,7 @@
 { lib, buildPythonPackage, fetchFromGitHub, flask }:
 
 buildPythonPackage rec {
-  pname = "Flask-Versioned";
+  pname = "flask-versioned";
   version = "0.9.4-20101221";
 
   src = fetchFromGitHub {
@@ -20,4 +20,3 @@ buildPythonPackage rec {
     maintainers = with maintainers; [ ];
   };
 }
-