diff --git a/pkgs/applications/audio/artyFX/default.nix b/pkgs/applications/audio/artyFX/default.nix
index 84914e3e798a5..2bf6b2a8046f4 100644
--- a/pkgs/applications/audio/artyFX/default.nix
+++ b/pkgs/applications/audio/artyFX/default.nix
@@ -8,7 +8,7 @@ stdenv.mkDerivation rec {
   src = fetchFromGitHub {
     owner = "openAVproductions";
     repo = "openAV-ArtyFX";
-    rev = "492587461b50d140455aa3c98d915eb8673bebf0";
+    rev = "8c542627d936a01b1d97825e7f26a8e95633f7aa";
     sha256 = "0wwg8ivnpyy0235bapjy4g0ij85zq355jwi6c1nkrac79p4z9ail";
   };
 
diff --git a/pkgs/applications/misc/usync/default.nix b/pkgs/applications/misc/usync/default.nix
index 8ab2a485a6491..cf51a53e7139d 100644
--- a/pkgs/applications/misc/usync/default.nix
+++ b/pkgs/applications/misc/usync/default.nix
@@ -6,9 +6,9 @@ stdenv.mkDerivation rec {
 
   src = fetchFromGitHub {
     owner = "ebzzry";
-    repo = pname;
-    rev = "9c87ea8a707a47c3d7f6ef94d07591c5ab594282";
-    sha256 = "1r05gw041fz9dkkb70zd6kqw9dd8dhpv87407qxqg43pd7x47kf4";
+    repo = "usync";
+    rev = "99f11b0c196a81843f55ca3456abcb85149b6d51";
+    sha256 = "16i1q8f0jmfd43rb8d70l2b383vr5ib4kh7iq3yd345q7xjz9c2j";
   };
 
   installPhase = ''
diff --git a/pkgs/applications/office/paperless/python-modules/django-crispy-forms.nix b/pkgs/applications/office/paperless/python-modules/django-crispy-forms.nix
index c470a56b8a11f..f8b91a94ccc79 100644
--- a/pkgs/applications/office/paperless/python-modules/django-crispy-forms.nix
+++ b/pkgs/applications/office/paperless/python-modules/django-crispy-forms.nix
@@ -1,15 +1,20 @@
-{ lib, buildPythonPackage, fetchFromGitHub
-, pytest_4, pytest-django, django }:
+{ lib
+, buildPythonPackage
+, fetchFromGitHub
+, pytestCheckHook
+, pytest-django
+, django
+}:
 
-buildPythonPackage {
+buildPythonPackage rec {
   pname = "django-crispy-forms";
-  version = "2019.04.21";
+  version = "1.10.0";
 
   src = fetchFromGitHub {
     owner = "django-crispy-forms";
     repo = "django-crispy-forms";
-    rev = "e25a5326697e5b545689b3a914e516404a6911bb";
-    sha256 = "12zqa76q6i7j47aqvhilivpbdplgp9zw2q8zfcjzlgclrqafaj39";
+    rev = version;
+    sha256 = "0y6kskfxgckb9npcgwx4zrs5n9px159zh9zhinhxi3i7wlriqpf5";
   };
 
   # For reasons unknown, the source dir must contain a dash
@@ -19,12 +24,10 @@ buildPythonPackage {
     export sourceRoot=source-
   '';
 
-  checkInputs = [ pytest_4 pytest-django django ];
+  checkInputs = [ django pytest-django pytestCheckHook ];
 
-  checkPhase = ''
-    PYTHONPATH="$(pwd):$PYTHONPATH" \
-    DJANGO_SETTINGS_MODULE=crispy_forms.tests.test_settings \
-      pytest crispy_forms/tests
+  preCheck = ''
+    export DJANGO_SETTINGS_MODULE=crispy_forms.tests.test_settings
   '';
 
   meta = with lib; {
diff --git a/pkgs/applications/radio/gnuradio/ais.nix b/pkgs/applications/radio/gnuradio/ais.nix
index 94556561439dc..8d6e8509772cf 100644
--- a/pkgs/applications/radio/gnuradio/ais.nix
+++ b/pkgs/applications/radio/gnuradio/ais.nix
@@ -1,10 +1,20 @@
-{ lib, stdenv, fetchFromGitHub, cmake, pkg-config, boost, gnuradio
-, makeWrapper, cppunit, gr-osmosdr, log4cpp
-, pythonSupport ? true, python, swig
+{ lib
+, stdenv
+, fetchFromGitHub
+, cmake
+, pkg-config
+, boost
+, gnuradio
+, makeWrapper
+, cppunit
+, gr-osmosdr
+, log4cpp
+, pythonSupport ? true
+, python
+, swig
+, fetchpatch
 }:
 
-assert pythonSupport -> python != null && swig != null;
-
 stdenv.mkDerivation {
   pname = "gr-ais";
   version = "2015-12-20";
@@ -12,14 +22,20 @@ stdenv.mkDerivation {
   src = fetchFromGitHub {
     owner = "bistromath";
     repo = "gr-ais";
-    # Upstream PR: https://github.com/bistromath/gr-ais/commit/8502d0252a2a1a9b8d1a71795eaeb5d820684054
-    rev = "8502d0252a2a1a9b8d1a71795eaeb5d820684054";
-    sha256 = "1b9j0kc74cw12a7jv4lii77dgzqzg2s8ndzp4xmisxksgva1qfvh";
+    rev = "cdc1f52745853f9c739c718251830eb69704b26e";
+    sha256 = "1vl3kk8xr2mh5lf31zdld7yzmwywqffffah8iblxdzblgsdwxfl6";
   };
 
+  patches = [
+    (fetchpatch {
+      url = "https://github.com/bistromath/gr-ais/commit/8502d0252a2a1a9b8d1a71795eaeb5d820684054.patch";
+      sha256 = "1cwalphldvf6dbhzwz1gi53z0cb4921qsvlz4138q7m6dxccvssg";
+    })
+  ];
+
   nativeBuildInputs = [ cmake makeWrapper pkg-config ];
   buildInputs = [ boost gnuradio cppunit gr-osmosdr log4cpp ]
-             ++ lib.optionals pythonSupport [ python swig ];
+    ++ lib.optionals pythonSupport [ python swig ];
 
   postInstall = ''
     for prog in "$out"/bin/*; do
diff --git a/pkgs/data/fonts/myrica/default.nix b/pkgs/data/fonts/myrica/default.nix
index aa5ee0ff1c380..c36292eb00141 100644
--- a/pkgs/data/fonts/myrica/default.nix
+++ b/pkgs/data/fonts/myrica/default.nix
@@ -5,6 +5,7 @@ fetchFromGitHub {
 
   owner = "tomokuni";
   repo = "Myrica";
+  # commit does not exist on any branch on the target repository
   rev = "b737107723bfddd917210f979ccc32ab3eb6dc20";
   sha256 = "187rklcibbkai6m08173ca99qn8v7xpdfdv0izpymmavj85axm12";
 
diff --git a/pkgs/data/fonts/siji/default.nix b/pkgs/data/fonts/siji/default.nix
index ea2d2b687d53b..adc6a79f10f49 100644
--- a/pkgs/data/fonts/siji/default.nix
+++ b/pkgs/data/fonts/siji/default.nix
@@ -1,11 +1,13 @@
-{ lib, stdenv, fetchzip, libfaketime, fonttosfnt, mkfontscale }:
+{ lib, stdenv, fetchFromGitHub, libfaketime, fonttosfnt, mkfontscale }:
 
 stdenv.mkDerivation rec {
   name = "siji-${version}";
   version = "2016-05-13";
 
-  src = fetchzip {
-    url = "https://github.com/stark/siji/archive/95369afac3e661cb6d3329ade5219992c88688c1.zip";
+  src = fetchFromGitHub {
+    owner = "stark";
+    repo = "siji";
+    rev = "3cbb7fe938c33aaadbb657803ea5946e5157d6e2";
     sha256 = "1408g4nxwdd682vjqpmgv0cp0bfnzzzwls62cjs9zrds16xa9dpf";
   };
 
diff --git a/pkgs/development/python-modules/greatfet/default.nix b/pkgs/development/python-modules/greatfet/default.nix
index b4048c922daee..7859d2f4c0870 100644
--- a/pkgs/development/python-modules/greatfet/default.nix
+++ b/pkgs/development/python-modules/greatfet/default.nix
@@ -1,13 +1,13 @@
 { lib, fetchFromGitHub, buildPythonPackage, isPy3k, future, pyusb, ipython, pygreat }:
 
-buildPythonPackage {
+buildPythonPackage rec {
   pname = "GreatFET";
   version = "2019.5.1.dev0";
 
   src = fetchFromGitHub {
     owner = "greatscottgadgets";
     repo = "greatfet";
-    rev = "a927f21d59ccface00635146103a807c1d2b0ad8";
+    rev = "v${version}";
     sha256 = "054vkx4xkbhxhh5grjbs9kw3pjkv1zapp91ysrqr0c8mg1pc7zxv";
   };
 
diff --git a/pkgs/development/python-modules/nmigen-soc/default.nix b/pkgs/development/python-modules/nmigen-soc/default.nix
index 4c15e65e62b29..afc0c63a38f89 100644
--- a/pkgs/development/python-modules/nmigen-soc/default.nix
+++ b/pkgs/development/python-modules/nmigen-soc/default.nix
@@ -15,7 +15,7 @@ buildPythonPackage rec {
   src = fetchFromGitHub {
     owner = "nmigen";
     repo = "nmigen-soc";
-    rev = "f1b009c7e075bca461d10ec963a7eaa3bf4dfc14";
+    rev = "f5b5cd563e8e8d081b0535c4554c02b5456ee8b4";
     sha256 = "04kjaq9qp6ac3h0r1wlb4jyz56bb52l1rikmz1x7azvnr10xhrad";
   };
 
diff --git a/pkgs/development/tools/database/pyrseas/default.nix b/pkgs/development/tools/database/pyrseas/default.nix
index 075cd5053beb6..930078b2dc72e 100644
--- a/pkgs/development/tools/database/pyrseas/default.nix
+++ b/pkgs/development/tools/database/pyrseas/default.nix
@@ -1,13 +1,13 @@
 { lib, pythonPackages, fetchFromGitHub }:
 
 let
-  pgdbconn = pythonPackages.buildPythonPackage {
+  pgdbconn = pythonPackages.buildPythonPackage rec {
     pname = "pgdbconn";
     version = "0.8.0";
     src = fetchFromGitHub {
       owner = "perseas";
       repo = "pgdbconn";
-      rev = "26c1490e4f32e4b5b925e5b82014ad106ba5b057";
+      rev = "v${version}";
       sha256 = "09r4idk5kmqi3yig7ip61r6js8blnmac5n4q32cdcbp1rcwzdn6z";
     };
     # The tests are impure (they try to access a PostgreSQL server)
diff --git a/pkgs/development/tools/trellis/default.nix b/pkgs/development/tools/trellis/default.nix
index 6ce1ad9a38aa8..8f9acd6c140c3 100644
--- a/pkgs/development/tools/trellis/default.nix
+++ b/pkgs/development/tools/trellis/default.nix
@@ -13,7 +13,7 @@ stdenv.mkDerivation rec {
 
   srcs = [
     (fetchFromGitHub {
-       owner  = "SymbiFlow";
+       owner  = "YosysHQ";
        repo   = "prjtrellis";
        rev    = "60c05b3f4e71fd78d4fba5c31f9974694245199e";
        sha256 = "1k37mxwxv9fpm6xnrxlqqap7zqh2dvgqncphj3asi2rz0kh07ppf";
@@ -21,7 +21,7 @@ stdenv.mkDerivation rec {
      })
 
     (fetchFromGitHub {
-      owner  = "SymbiFlow";
+      owner  = "YosysHQ";
       repo   = "prjtrellis-db";
       rev    = "2cf058e7a3ba36134d21e34823e9b2ecaaceac2c";
       sha256 = "1hjaw5jkwiaiznm2z0smy88m2cdz63cd51z4nibajfih7ikvkj6g";
diff --git a/pkgs/games/openmw/default.nix b/pkgs/games/openmw/default.nix
index 23572998d034a..7c8f4990a6190 100644
--- a/pkgs/games/openmw/default.nix
+++ b/pkgs/games/openmw/default.nix
@@ -6,6 +6,7 @@ let
     src = fetchFromGitHub {
       owner = "OpenMW";
       repo = "osg";
+      # commit does not exist on any branch on the target repository
       rev = "1556cd7966ebc1c80b6626988d2b25fb43a744cf";
       sha256 = "0d74hijzmj82nx3jkv5qmr3pkgvplra0b8fbjx1y3vmzxamb0axd";
     };
diff --git a/pkgs/games/openra/mods.nix b/pkgs/games/openra/mods.nix
index 4a79125dc1817..cf8cd433c2942 100644
--- a/pkgs/games/openra/mods.nix
+++ b/pkgs/games/openra/mods.nix
@@ -123,6 +123,7 @@ in {
       src = fetchFromGitHub {
         owner = "IceReaper";
         repo = "OpenRA" ;
+        # commit does not exist on any branch on the target repository
         rev = "4e8eab4ca00d1910203c8a103dfd2c002714daa8";
         sha256 = "1yyqparf93x8yzy1f46gsymgkj5jls25v2yc7ighr3f7mi3igdvq";
         name = "engine";
diff --git a/pkgs/games/snipes/default.nix b/pkgs/games/snipes/default.nix
index 66188ba0efe8f..01b24ee434c3d 100644
--- a/pkgs/games/snipes/default.nix
+++ b/pkgs/games/snipes/default.nix
@@ -13,13 +13,15 @@ in stdenv.mkDerivation {
   src = fetchFromGitHub {
     owner  = "Davidebyzero";
     repo   = "Snipes";
-    rev    = "343e14104b7848eb1f882401888e685b7918ef9f";
-    sha256 = "1rl70d5miak34warbwfv27z11vln4lvf7maqqc78z0gdc5zivdv2";
+    rev    = "594af45108e07aa4159c3babc9b5e53609c3fd6e";
+    sha256 = "0gmh38swm74jmljy0bq27ipqzb4h8y9rzwc1j6harbd9qqz5knac";
   };
 
   postPatch = ''
     substitute config-sample.h config.h \
       --replace SnipesConsole.ttf $out/share/snipes/SnipesConsole.ttf
+    substituteInPlace GNUmakefile \
+      --replace 'CFLAGS=-Werror -Wall' 'CFLAGS=-Wall'
   '';
 
   enableParallelBuilding = true;
diff --git a/pkgs/misc/emulators/retroarch/cores.nix b/pkgs/misc/emulators/retroarch/cores.nix
index c1b60ad63b2f2..7d0ba259dc511 100644
--- a/pkgs/misc/emulators/retroarch/cores.nix
+++ b/pkgs/misc/emulators/retroarch/cores.nix
@@ -925,8 +925,8 @@ in with lib.licenses;
     src = fetchFromGitHub {
       owner = "snes9xgit";
       repo = core;
-      rev = "6db918cfe32b157239da44096091c212fdfb3b60";
-      sha256 = "0y3jhy50qdhhfglybys9m0fgk9r24ksdcgv5iqpyxy5a4cjvhv8j";
+      rev = "bd9246ddd75a5e9f78d6189c8c57754d843630f7";
+      sha256 = "10fm7ah3aha9lf4k9hgw0dlhdvshzpig2d0ylcb12gf9zz0i22ns";
     };
     description = "Port of SNES9x git to libretro";
     license = "Non-commercial";
diff --git a/pkgs/os-specific/linux/acpi-call/default.nix b/pkgs/os-specific/linux/acpi-call/default.nix
index 87535b92e4659..b79f0bd84f2f1 100644
--- a/pkgs/os-specific/linux/acpi-call/default.nix
+++ b/pkgs/os-specific/linux/acpi-call/default.nix
@@ -7,8 +7,8 @@ stdenv.mkDerivation rec {
   src = fetchFromGitHub {
     owner = "nix-community";
     repo = "acpi_call";
-    rev = "3d7c9fe5ed3fc5ed5bafd39d54b1fdc7a09ce710";
-    sha256 = "09kp8zl392h99wjwzqrdw2xcfnsc944hzmfwi8n1y7m2slpdybv3";
+    rev = "fe4cd0124099b88b61f83006023bc0d95e742e75";
+    sha256 = "1rksbg78i7y2wzam9p6kbhx8rmkaiq0kqg8nj7k0j6d25m79289s";
   };
 
   hardeningDisable = [ "pic" ];
diff --git a/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix b/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix
index b1874bf38202a..619bf48b736c2 100644
--- a/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix
+++ b/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix
@@ -7,6 +7,7 @@ buildLinux (args // {
   src = fetchFromGitHub {
     owner = "koverstreet";
     repo = "bcachefs";
+    # commit does not exist on any branch on the target repository
     rev = "6a505b63ed3003faf5000f19fd08bbd477d93fbc";
     sha256 = "1rf34gzv9npafp1c3i6lymk3b0gnqp4rb0wl33pw6yrpgnsry3cc";
   };
diff --git a/pkgs/os-specific/linux/rtlwifi_new/default.nix b/pkgs/os-specific/linux/rtlwifi_new/default.nix
index ef71cd82541ca..12f87f409552d 100644
--- a/pkgs/os-specific/linux/rtlwifi_new/default.nix
+++ b/pkgs/os-specific/linux/rtlwifi_new/default.nix
@@ -12,6 +12,7 @@ in stdenv.mkDerivation rec {
   src = fetchFromGitHub {
     owner = "rtlwifi-linux";
     repo = "rtlwifi_new";
+    # commit does not exist on any branch on the target repository
     rev = "a108e3de87c2ed30b71c3c4595b79ab7a2f9e348";
     sha256 = "15kjs9i9vvmn1cdzccd5cljf3m45r4ssm65klkj2fdkf3kljj38k";
   };
diff --git a/pkgs/tools/misc/hdl-dump/default.nix b/pkgs/tools/misc/hdl-dump/default.nix
index 6a6af1391bda5..e5f3afb03d573 100644
--- a/pkgs/tools/misc/hdl-dump/default.nix
+++ b/pkgs/tools/misc/hdl-dump/default.nix
@@ -1,20 +1,19 @@
-{ lib, stdenv
+{ lib
+, stdenv
 , fetchFromGitHub
 , upx
 }:
 
-let
-  version = "20202807";
+stdenv.mkDerivation rec {
   pname = "hdl-dump";
-in stdenv.mkDerivation {
-  inherit pname version;
+  version = "20202807";
 
   # Using AkuHAK's repo because playstation2's repo is outdated
   src = fetchFromGitHub {
     owner = "AKuHAK";
     repo = pname;
-    rev = "be37e112a44772a1341c867dc3dfee7381ce9e59";
-    sha256 = "0akxak6hm11h8z6jczxgr795s4a8czspwnhl3swqxp803dvjdx41";
+    rev = "0c98b235c83c0fca1da93648f05ea5f940a4aee0";
+    sha256 = "1s3wflqjjlcslpa9n5chr8dbamhmfk88885dzw68apz4vf6g27iq";
   };
 
   buildInputs = [ upx ];