diff --git a/.cirrus.yml b/.cirrus.yml
index d947b559..a493b04f 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -14,3 +14,4 @@ task:
   smoketest_generic_script: export NEXTPNR=$(pwd)/build/nextpnr-generic && cd generic/examples && ./simple.sh && ./simtest.sh
   regressiontest_ice40_script: make -j $(nproc) -C tests/ice40/regressions NPNR=$(pwd)/build/nextpnr-ice40
   regressiontest_ecp5_script: make -j $(nproc) -C tests/ecp5/regressions NPNR=$(pwd)/build/nextpnr-ecp5
+  archcheck_script: BUILD_DIR=$(pwd)/build ./.cirrus/archcheck.sh
diff --git a/.cirrus/Dockerfile.ubuntu16.04 b/.cirrus/Dockerfile.ubuntu16.04
index 2dd5b360..d98bb014 100644
--- a/.cirrus/Dockerfile.ubuntu16.04
+++ b/.cirrus/Dockerfile.ubuntu16.04
@@ -26,9 +26,9 @@ RUN set -e -x ;\
 RUN set -e -x ;\
     mkdir -p /usr/local/src ;\
     cd /usr/local/src ;\
-    git clone --recursive https://github.com/cliffordwolf/icestorm.git ;\
+    git clone --recursive https://github.com/YosysHQ/icestorm.git ;\
     cd icestorm ;\
-    git reset --hard 3a2bfee5cbc0558641668114260d3f644d6b7c83 ;\
+    git reset --hard 4bc68c9620e6be20f8fe10d20f84681d80beac23 ;\
     make -j $(nproc) ;\
     make install
 
@@ -47,7 +47,7 @@ RUN set -e -x ;\
     cd /usr/local/src ;\
     git clone --recursive https://github.com/YosysHQ/prjtrellis.git ;\
     cd prjtrellis ;\
-    git reset --hard 668ce3492cbe1566c61760f06bdf676f6fb265c3 ;\
+    git reset --hard f93243b000c52b755c70829768d2ae6bcf7bb91a ;\
     cd libtrellis ;\
     cmake . ;\
     make -j $(nproc) ;\
diff --git a/.cirrus/archcheck.sh b/.cirrus/archcheck.sh
new file mode 100755
index 00000000..fde19216
--- /dev/null
+++ b/.cirrus/archcheck.sh
@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+set -ex
+echo "Running archcheck!"
+${BUILD_DIR}/nextpnr-ice40 --hx8k --package ct256 --test
+${BUILD_DIR}/nextpnr-ice40 --up5k --package sg48 --test
+${BUILD_DIR}/nextpnr-ecp5 --um5g-25k --package CABGA381 --test
diff --git a/common/archcheck.cc b/common/archcheck.cc
index 3d9e4e76..7b727e9b 100644
--- a/common/archcheck.cc
+++ b/common/archcheck.cc
@@ -47,14 +47,14 @@ void archcheck_names(const Context *ctx)
         WireId wire2 = ctx->getWireByName(name);
         log_assert(wire == wire2);
     }
-
+#ifndef ARCH_ECP5
     log_info("Checking pip names..\n");
     for (PipId pip : ctx->getPips()) {
         IdString name = ctx->getPipName(pip);
         PipId pip2 = ctx->getPipByName(name);
         log_assert(pip == pip2);
     }
-
+#endif
     log_break();
 }
 
diff --git a/ecp5/arch.h b/ecp5/arch.h
index 0f351319..8c7e13e4 100644
--- a/ecp5/arch.h
+++ b/ecp5/arch.h
@@ -496,9 +496,11 @@ struct Arch : BaseCtx
 
     // -------------------------------------------------
 
+    static const int max_loc_bels = 20;
+
     int getGridDimX() const { return chip_info->width; };
     int getGridDimY() const { return chip_info->height; };
-    int getTileBelDimZ(int, int) const { return 4; };
+    int getTileBelDimZ(int, int) const { return max_loc_bels; };
     int getTilePipDimZ(int, int) const { return 1; };
 
     // -------------------------------------------------
@@ -520,7 +522,6 @@ struct Arch : BaseCtx
 
     uint32_t getBelChecksum(BelId bel) const { return bel.index; }
 
-    const int max_loc_bels = 20;
     int getBelFlatIndex(BelId bel) const
     {
         return (bel.location.y * chip_info->width + bel.location.x) * max_loc_bels + bel.index;
diff --git a/ice40/arch.cc b/ice40/arch.cc
index 52246001..be346fd7 100644
--- a/ice40/arch.cc
+++ b/ice40/arch.cc
@@ -192,7 +192,11 @@ BelRange Arch::getBelsByTile(int x, int y) const
     // are used
     BelRange br;
 
-    br.b.cursor = Arch::getBelByLocation(Loc(x, y, 0)).index;
+    for (int i = 0; i < 4; i++) {
+        br.b.cursor = Arch::getBelByLocation(Loc(x, y, i)).index;
+        if (br.b.cursor != -1)
+            break;
+    }
     br.e.cursor = br.b.cursor;
 
     if (br.e.cursor != -1) {
diff --git a/ice40/chipdb.py b/ice40/chipdb.py
index 7b3ad999..efdde1a1 100644
--- a/ice40/chipdb.py
+++ b/ice40/chipdb.py
@@ -1060,7 +1060,7 @@ for tile_xy, tile_type in sorted(tiles.items()):
         if ec[1] == tile_xy[0] and ec[2] == tile_xy[1]:
             add_bel_ec(ec)
 
-for ec in sorted(extra_cells.keys()):
+for ec in sorted(extra_cells.keys(), key=lambda ec: (ec[1], ec[2], ec[3], ec[0])):
     if ec[1] in (0, dev_width - 1) and ec[2] in (0, dev_height - 1):
         add_bel_ec(ec)