diff --git a/.gdbinit b/.gdbinit
new file mode 100644
index 0000000..c1022cc
--- /dev/null
+++ b/.gdbinit
@@ -0,0 +1,8 @@
+file /nix/store/ijxm784gr0sx5p4d92rlag0ippyd0mvm-am-kernel-riscv32-none-elf-2024-07-10/libexec/am-kernels/bench
+
+set substitute-path /build/am-kernels /home/xin/repo/ysyx-workbench/am-kernels
+set substitute-path /build/abstract-machine /home/xin/repo/ysyx-workbench/abstract-machine
+# set debug remote 1
+target remote /tmp/gdbstub-diffu.sock
+break *halt + 24
+
diff --git a/.gitea/workflows/build.yml b/.gitea/workflows/build.yml
new file mode 100644
index 0000000..80bedb4
--- /dev/null
+++ b/.gitea/workflows/build.yml
@@ -0,0 +1,20 @@
+name: Build nix packages
+on: [push]
+
+jobs:
+  build-matrix:
+    runs-on: nix
+    strategy:
+      matrix:
+        package: [ "default" ]
+    steps:
+      - uses: https://github.com/cachix/cachix-action@v14
+        with:
+          name: ysyx
+          authToken: '${{ secrets.CACHIX_SIGNING_KEY }}'
+
+      - uses: actions/checkout@v4
+
+      - name: Build
+        run: |
+          nix build -L .#${{ matrix.package }}
diff --git a/difftest.toml b/difftest.toml
index 9d9bad8..3fdac6d 100644
--- a/difftest.toml
+++ b/difftest.toml
@@ -1,14 +1,17 @@
 # ref = "/home/xin/repo/spike-diff/build/lib/libspike-diff.so"
 # ref-prefix = "spike_"
+ref= "/home/xin/repo/ysyx-workbench/nemu/build/riscv32-nemu-interpreter-so"
+ref-prefix = "nemu_"
 # dut = "/home/xin/repo/ysyx-workbench/nemu/build/riscv32-nemu-interpreter-so"
 # dut-prefix = "nemu_"
 
-ref = /home/xin/repo/ysyx-workbench/nemu/build/riscv32-nemu-interpreter-so
-ref-prefix = nemu_
-dut = "/home/xin/repo/spike-diff/build/lib/libspike-diff.so"
-dut-prefix = "spike_"
+dut = "/home/xin/repo/ysyx-workbench/npc/build/csrc/Flow/libFlow.so"
+dut-prefix = "npc_"
+
+# dut = "/home/xin/repo/ysyx-workbench/nemu/build/riscv32-nemu-interpreter-so"
+# dut-prefix = "nemu_"
 listen = "/tmp/gdbstub-diffu.sock"
 # listen = "127.0.0.1:1234"
-# memory = "/nix/store/37986mdgsqm5m8w74k0f5llzqhxgsbnv-am-kernel-riscv32-none-elf-2024-07-10/share/am-kernels/string.bin"
-memory = "./add.bin"
+images-path = "/nix/store/z7mc0y608145cfwlb2g1gsii7bij7li1-am-kernel-riscv32-none-elf-2024-07-10/share/am-kernels"
+memory = "bench.bin"
 # g = true