diff --git a/pkgs/development/compilers/nextpnr/default.nix b/pkgs/development/compilers/nextpnr/default.nix
index ed64d9e6a66d..16f0a8348d1c 100644
--- a/pkgs/development/compilers/nextpnr/default.nix
+++ b/pkgs/development/compilers/nextpnr/default.nix
@@ -14,15 +14,15 @@ let
 in
 stdenv.mkDerivation rec {
   pname = "nextpnr";
-  version = "2021.11.24"; # tagged as 0.1, but we'll keep tracking HEAD
+  version = "2021.15.21";
 
   srcs = [
     (fetchFromGitHub {
-      owner  = "YosysHQ";
-      repo   = "nextpnr";
-      rev    = "fd2d4a8f999947ece42f791e19ddc4c2d8b823f2";
-      sha256 = "sha256-bGh3svJeVRJO0rTnSYoTndeQrTENx6j9t+GCGX4RX4k=";
-      name   = "nextpnr";
+      owner = "YosysHQ";
+      repo  = "nextpnr";
+      rev   = "d04cfd5f0f6da184f5b8a03f0ce18fbd1d98eca3";
+      hash  = "sha256-gm/+kwIZ/m10+KuCJoK45F56nKZD3tM0myHwbFKIKAs=";
+      name  = "nextpnr";
     })
     (fetchFromGitHub {
       owner  = "YosysHQ";
diff --git a/pkgs/development/embedded/fpga/trellis/default.nix b/pkgs/development/embedded/fpga/trellis/default.nix
index 2289b6fb6398..32a4bcdac073 100644
--- a/pkgs/development/embedded/fpga/trellis/default.nix
+++ b/pkgs/development/embedded/fpga/trellis/default.nix
@@ -1,25 +1,28 @@
 { lib, stdenv, fetchFromGitHub, python3, boost, cmake }:
 
 let
-  rev = "03e0070f263fbe31c247de61d259544722786210";
+  rev = "2f06397673bbca3da11928d538b8ab7d01c944c6";
   # git describe --tags
-  realVersion = "1.0-532-g${builtins.substring 0 7 rev}";
+  realVersion = "1.0-534-g${builtins.substring 0 7 rev}";
 in stdenv.mkDerivation rec {
   pname = "trellis";
-  version = "2021-09-01";
+  version = "2021-12-14";
 
   srcs = [
     (fetchFromGitHub {
        owner  = "YosysHQ";
        repo   = "prjtrellis";
        inherit rev;
-       sha256 = "joQMsjVj8d3M3IaqOkfVQ1I5qPDM8HHJiye+Ak8f3dg=";
+       hash   = "sha256-m5CalAIbzY2bhOvpBbPBeLZeDp+itk1HlRsSmtiddaA=";
        name   = "trellis";
      })
 
     (fetchFromGitHub {
       owner  = "YosysHQ";
       repo   = "prjtrellis-db";
+      # note: the upstream submodule points to revision 0ee729d20eaf,
+      # but that's just the tip of the branch that was merged into master.
+      # fdf4bf275a is the merge commit itself
       rev    = "fdf4bf275a7402654bc643db537173e2fbc86103";
       sha256 = "eDq2wU2pnfK9bOkEVZ07NQPv02Dc6iB+p5GTtVBiyQA=";
       name   = "trellis-database";