diff --git a/third_party/cgit/Makefile b/third_party/cgit/Makefile
index d13c5bd13..9153a393f 100644
--- a/third_party/cgit/Makefile
+++ b/third_party/cgit/Makefile
@@ -14,7 +14,7 @@ htmldir = $(docdir)
 pdfdir = $(docdir)
 mandir = $(prefix)/share/man
 SHA1_HEADER = <openssl/sha.h>
-GIT_VER = 2.32.0
+GIT_VER = 2.34.0
 GIT_URL = https://www.kernel.org/pub/software/scm/git/git-$(GIT_VER).tar.xz
 INSTALL = install
 COPYTREE = cp -r
diff --git a/third_party/cgit/cgit.c b/third_party/cgit/cgit.c
index 08d81a1d4..4b2d86c88 100644
--- a/third_party/cgit/cgit.c
+++ b/third_party/cgit/cgit.c
@@ -428,7 +428,7 @@ static void prepare_context(void)
 	ctx.page.modified = time(NULL);
 	ctx.page.expires = ctx.page.modified;
 	ctx.page.etag = NULL;
-	string_list_init(&ctx.cfg.mimetypes, 1);
+	string_list_init_dup(&ctx.cfg.mimetypes);
 	if (ctx.env.script_name)
 		ctx.cfg.script_name = xstrdup(ctx.env.script_name);
 	if (ctx.env.query_string)
diff --git a/third_party/nixpkgs/default.nix b/third_party/nixpkgs/default.nix
index f08b46b63..3048f9229 100644
--- a/third_party/nixpkgs/default.nix
+++ b/third_party/nixpkgs/default.nix
@@ -13,16 +13,16 @@ let
   # nixos-unstable, and the current stable channel of the latest NixOS
   # release.
 
-  # Tracking nixos-unstable as of 2021-11-24.
+  # Tracking nixos-unstable as of 2021-12-05.
   unstableHashes = {
-    commit = "39cb89ef2ffcbef8d2ac2d52267ac69121a6becb";
-    sha256 = "1x9vzpay56ap4hgfq1giz00050crdngv5jkxgkxzx276mzhw93na";
+    commit = "c71f061c68ba8ce53471b767d5049cbd0f3d8490";
+    sha256 = "1s2lmxswx30z80abccvrcygpnys3csbaygjdlw5i0lk4nwslnkmn";
   };
 
-  # Tracking nixos-21.05 as of 2021-11-24.
+  # Tracking nixos-21.05 as of 2021-12-07.
   stableHashes = {
-    commit = "09650059d7f5ae59a7f0fb2dd3bfc6d2042a74de";
-    sha256 = "0f06zcc8mh934fya0hwzklmga238yxiyfp183y48vyzkdsg7xgn0";
+    commit = "4a8751d694b46340072d95409804f59b98326f44";
+    sha256 = "14pmmd82s0anknd6g57i0c1795766bvylqalf9kz730q1v0ransl";
   };
 
   # import the nixos-unstable package set, or optionally use the
diff --git a/third_party/overlays/emacs.nix b/third_party/overlays/emacs.nix
index 71645893f..4b55a0081 100644
--- a/third_party/overlays/emacs.nix
+++ b/third_party/overlays/emacs.nix
@@ -2,10 +2,10 @@
 { ... }:
 
 let
-  # from 2021-11-14
-  commit = "c75b7c047cc4635b0ecdedfd4ad78e1ac76e41c5";
+  # from 2021-12-07
+  commit = "2f14e98a92505c517a8364c3a5e614592fbea4f4";
   src = builtins.fetchTarball {
     url = "https://github.com/nix-community/emacs-overlay/archive/${commit}.tar.gz";
-    sha256 = "06if42qy22xni3gd9hqqq6yhama20qn402asalj16mxi1rxx4kgz";
+    sha256 = "16i16pm3bm43fj85n5bafghak0asi7p9xpyshpls6yyh85chcdb5";
   };
 in import src