diff --git a/pkgs/tools/misc/grc/default.nix b/pkgs/tools/misc/grc/default.nix
index cd3ea6eda6f0b..035924408189c 100644
--- a/pkgs/tools/misc/grc/default.nix
+++ b/pkgs/tools/misc/grc/default.nix
@@ -2,10 +2,10 @@
 
 stdenv.mkDerivation rec {
   version = "1.4";
-  name    = "grc_${version}";
+  name    = "grc-${version}";
 
   src = fetchurl {
-    url    = "http://korpus.juls.savba.sk/~garabik/software/grc/${name}.tar.gz";
+    url    = "http://korpus.juls.savba.sk/~garabik/software/grc/grc_${version}.tar.gz";
     sha256 = "1l7lskxfjk32kkv4aaqw5qcxvh972nab3x2jzy67m1aa0zpcbzdv";
   };
 
diff --git a/pkgs/tools/security/aespipe/default.nix b/pkgs/tools/security/aespipe/default.nix
index 9e4b8d12712a7..96de0e0fbe4a0 100644
--- a/pkgs/tools/security/aespipe/default.nix
+++ b/pkgs/tools/security/aespipe/default.nix
@@ -2,10 +2,10 @@
 
 stdenv.mkDerivation rec {
   name = "aespipe-${version}";
-  version = "v2.4c";
+  version = "2.4c";
 
   src = fetchurl {
-    url = "mirror://sourceforge/loop-aes/aespipe/${name}.tar.bz2";
+    url = "mirror://sourceforge/loop-aes/aespipe/aespipe-v${version}.tar.bz2";
     sha256 = "0pl49jnjczjvfxwm9lw576qsjm1lxh8gc4g776l904cixaz90096";
   };
 
diff --git a/pkgs/top-level/perl-packages.nix b/pkgs/top-level/perl-packages.nix
index fa8df33edf3b8..ef2372b501253 100644
--- a/pkgs/top-level/perl-packages.nix
+++ b/pkgs/top-level/perl-packages.nix
@@ -6185,9 +6185,9 @@ let self = _self // overrides; _self = with self; {
   };
 
   NetSNMP = buildPerlPackage rec {
-    name = "Net-SNMP-v6.0.1";
+    name = "Net-SNMP-6.0.1";
     src = fetchurl {
-      url = "mirror://cpan/authors/id/D/DT/DTOWN/${name}.tar.gz";
+      url = "mirror://cpan/authors/id/D/DT/DTOWN/Net-SNMP-v6.0.1.tar.gz";
       sha256 = "0hdpn1cw52x8cw24m9ayzpf4rwarm0khygn1sv3wvwxkrg0pphql";
     };
     doCheck = false; # The test suite fails, see https://rt.cpan.org/Public/Bug/Display.html?id=85799
@@ -7590,7 +7590,7 @@ let self = _self // overrides; _self = with self; {
   };
 
   SVK = buildPerlPackage {
-    name = "SVK-v2.0.2";
+    name = "SVK-2.0.2";
     src = fetchurl {
       url = mirror://cpan/authors/id/C/CL/CLKAO/SVK-v2.0.2.tar.gz;
       sha256 = "0c4m2q7cvzwh9kk1nc1vd8lkxx2kss5nd4k20dpkal4c7735jns0";
@@ -8680,9 +8680,9 @@ let self = _self // overrides; _self = with self; {
   };
 
   TextRecordParser = buildPerlPackage rec {
-    name = "Text-RecordParser-v1.5.0";
+    name = "Text-RecordParser-1.5.0";
     src = fetchurl {
-      url = "mirror://cpan/authors/id/K/KC/KCLARK/${name}.tar.gz";
+      url = "mirror://cpan/authors/id/K/KC/KCLARK/Text-RecordParser-v1.5.0.tar.gz";
       sha256 = "0zlwpayjnpjani3v3hgi77207i3n5fppcxww20chdldx98dkj7jm";
     };
 
@@ -8743,7 +8743,7 @@ let self = _self // overrides; _self = with self; {
   };
 
   TestTrap = buildPerlPackage {
-    name = "Test-Trap-v0.2.2";
+    name = "Test-Trap-0.2.2";
     src = fetchurl {
       url = mirror://cpan/authors/id/E/EB/EBHANSSEN/Test-Trap-v0.2.2.tar.gz;
       sha256 = "1ci5ag9pm850ww55n2929skvw3avy6xcrwmmi2yyn0hifxx9dybs";
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index ee19aa850d39b..331978e9c9d5d 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -5225,11 +5225,11 @@ pythonPackages = modules // import ./python-packages-generated.nix {
 
 
   pymacs = pkgs.stdenv.mkDerivation rec {
-    version = "v0.25";
+    version = "0.25";
     name = "Pymacs-${version}";
 
     src = fetchurl {
-      url = "https://github.com/pinard/Pymacs/tarball/${version}";
+      url = "https://github.com/pinard/Pymacs/tarball/v${version}";
       name = "${name}.tar.gz";
       sha256 = "1hmy76c5igm95rqbld7gvk0az24smvc8hplfwx2f5rhn6frj3p2i";
     };