diff --git a/difftest/offline.nix b/difftest/offline.nix
new file mode 100644
index 000000000..6cb220d28
--- /dev/null
+++ b/difftest/offline.nix
@@ -0,0 +1,40 @@
+{ lib
+, elaborateConfig
+, rustPlatform
+, libspike
+, libspike_interfaces
+}:
+
+rustPlatform.buildRustPackage {
+  name = "offline";
+  src = with lib.fileset; toSource {
+    root = ./.;
+    fileset = unions [
+      ./spike_rs
+      ./offline
+      ./dpi_common
+      ./dpi_t1
+      ./test_common
+      ./Cargo.lock
+      ./Cargo.toml
+    ];
+  };
+
+  buildFeatures = [];
+  buildAndTestSubdir = "./offline";
+
+  env = {
+    SPIKE_LIB_DIR = "${libspike}/lib";
+    SPIKE_INTERFACES_LIB_DIR = "${libspike_interfaces}/lib";
+    DESIGN_VLEN = elaborateConfig.parameter.vLen;
+    DESIGN_DLEN = elaborateConfig.parameter.dLen;
+    SPIKE_ISA_STRING =
+      "rv32gc_" +
+      (builtins.concatStringsSep "_" elaborateConfig.parameter.extensions)
+      + "_Zvl${toString elaborateConfig.parameter.vLen}b";
+  };
+
+  cargoLock = {
+    lockFile = ./Cargo.lock;
+  };
+}
diff --git a/difftest/offline/src/main.rs b/difftest/offline/src/main.rs
index 302e3df5d..9de4281f7 100644
--- a/difftest/offline/src/main.rs
+++ b/difftest/offline/src/main.rs
@@ -7,6 +7,7 @@ use std::path::PathBuf;
 use clap::Parser;
 use spike_rs::runner::{SpikeArgs, SpikeRunner};
 use tracing::info;
+use tracing_subscriber::{EnvFilter, FmtSubscriber};
 
 use crate::difftest::Difftest;
 
@@ -94,18 +95,12 @@ fn main() -> anyhow::Result<()> {
 }
 
 fn setup_logger() {
-  // setup log
-  // let log_level: Level = self.log_level.parse()?;
-  // let global_logger = FmtSubscriber::builder()
-  //   .with_env_filter(EnvFilter::from_default_env())
-  //   .with_max_level(log_level)
-  //   .without_time()
-  //   .with_target(false)
-  //   .with_ansi(true)
-  //   .compact()
-  //   .finish();
-  // tracing::subscriber::set_global_default(global_logger)
-  //   .expect("internal error: fail to setup log subscriber");
-  // Ok(())
-  todo!()
+  let global_logger = FmtSubscriber::builder()
+    .with_env_filter(EnvFilter::from_default_env())
+    .without_time()
+    .with_target(false)
+    .compact()
+    .finish();
+  tracing::subscriber::set_global_default(global_logger)
+    .expect("internal error: fail to setup log subscriber");
 }
diff --git a/nix/t1/default.nix b/nix/t1/default.nix
index 6ffd5ff4f..87158d38c 100644
--- a/nix/t1/default.nix
+++ b/nix/t1/default.nix
@@ -131,6 +131,8 @@ lib.makeScope newScope
           # FIXME: vcs-emu should have offline check instead of using verilator one
           vcs-emu = ipSelf.callPackage ./vcs.nix { };
           vcs-emu-trace = ipSelf.callPackage ./vcs.nix { vcs-dpi-lib = ipSelf.vcs-dpi-lib-trace; };
+
+          offline = ipSelf.callPackage ../../difftest/offline.nix { };
         });
 
         subsystem = rec {
diff --git a/nix/t1/run-vcs-emulation.nix b/nix/t1/run-vcs-emulation.nix
index 1575979e8..857fe6bab 100644
--- a/nix/t1/run-vcs-emulation.nix
+++ b/nix/t1/run-vcs-emulation.nix
@@ -1,5 +1,4 @@
-# FIXME: we should have offline check for VCS, importing offline check from verilator-emu is weird
-{ lib, stdenvNoCC, zstd, jq, verilator-emu }:
+{ lib, stdenvNoCC, zstd, jq, offline }:
 emulator:
 testCase:
 
@@ -71,7 +70,7 @@ stdenvNoCC.mkDerivation (finalAttr: {
     )
     offlineCheckArgs="''${offlineCheckArgsArray[@]}"
     echo -e "[nix] running offline check: \033[0;34m${emulator}/bin/offline $offlineCheckArgs\033[0m"
-    "${verilator-emu}/bin/offline" $offlineCheckArgs &> $out/offline-check-journal
+    "${offline}/bin/offline" $offlineCheckArgs &> $out/offline-check-journal
 
     printf "$?" > $out/offline-check-status
     if [ "$(cat $out/offline-check-status)" != "0" ]; then