diff --git a/codex-rs/core/src/util.rs b/codex-rs/core/src/util.rs
index 14bcc16d..a7c14852 100644
--- a/codex-rs/core/src/util.rs
+++ b/codex-rs/core/src/util.rs
@@ -5,6 +5,8 @@ use rand::Rng;
 use tokio::sync::Notify;
 use tracing::debug;
 
+use crate::config::Config;
+
 const INITIAL_DELAY_MS: u64 = 200;
 const BACKOFF_FACTOR: f64 = 1.3;
 
@@ -33,26 +35,20 @@ pub(crate) fn backoff(attempt: u64) -> Duration {
     Duration::from_millis((base as f64 * jitter) as u64)
 }
 
-/// Return `true` if the current working directory is inside a Git repository.
+/// Return `true` if the project folder specified by the `Config` is inside a
+/// Git repository.
 ///
-/// The check walks up the directory hierarchy looking for a `.git` folder. This
+/// The check walks up the directory hierarchy looking for a `.git` file or
+/// directory (note `.git` can be a file that contains a `gitdir` entry). This
 /// approach does **not** require the `git` binary or the `git2` crate and is
-/// therefore fairly lightweight.  It intentionally only looks for the
-/// presence of a *directory* named `.git` – this is good enough for regular
-/// work‑trees and bare repos that live inside a work‑tree (common for
-/// developers running Codex locally).
+/// therefore fairly lightweight.
 ///
 /// Note that this does **not** detect *work‑trees* created with
 /// `git worktree add` where the checkout lives outside the main repository
-/// directory.  If you need Codex to work from such a checkout simply pass the
+/// directory. If you need Codex to work from such a checkout simply pass the
 /// `--allow-no-git-exec` CLI flag that disables the repo requirement.
-pub fn is_inside_git_repo() -> bool {
-    // Best‑effort: any IO error is treated as "not a repo" – the caller can
-    // decide what to do with the result.
-    let mut dir = match std::env::current_dir() {
-        Ok(d) => d,
-        Err(_) => return false,
-    };
+pub fn is_inside_git_repo(config: &Config) -> bool {
+    let mut dir = config.cwd.to_path_buf();
 
     loop {
         if dir.join(".git").exists() {
diff --git a/codex-rs/exec/src/lib.rs b/codex-rs/exec/src/lib.rs
index 4f9c94b5..1bd5069e 100644
--- a/codex-rs/exec/src/lib.rs
+++ b/codex-rs/exec/src/lib.rs
@@ -47,23 +47,6 @@ pub async fn run_main(cli: Cli) -> anyhow::Result<()> {
 
     assert_api_key(stderr_with_ansi);
 
-    if !skip_git_repo_check && !is_inside_git_repo() {
-        eprintln!("Not inside a Git repo and --skip-git-repo-check was not specified.");
-        std::process::exit(1);
-    }
-
-    // TODO(mbolin): Take a more thoughtful approach to logging.
-    let default_level = "error";
-    let _ = tracing_subscriber::fmt()
-        .with_env_filter(
-            EnvFilter::try_from_default_env()
-                .or_else(|_| EnvFilter::try_new(default_level))
-                .unwrap(),
-        )
-        .with_ansi(stderr_with_ansi)
-        .with_writer(std::io::stderr)
-        .try_init();
-
     let sandbox_policy = if full_auto {
         Some(SandboxPolicy::new_full_auto_policy())
     } else {
@@ -85,6 +68,24 @@ pub async fn run_main(cli: Cli) -> anyhow::Result<()> {
         cwd: cwd.map(|p| p.canonicalize().unwrap_or(p)),
     };
     let config = Config::load_with_overrides(overrides)?;
+
+    if !skip_git_repo_check && !is_inside_git_repo(&config) {
+        eprintln!("Not inside a Git repo and --skip-git-repo-check was not specified.");
+        std::process::exit(1);
+    }
+
+    // TODO(mbolin): Take a more thoughtful approach to logging.
+    let default_level = "error";
+    let _ = tracing_subscriber::fmt()
+        .with_env_filter(
+            EnvFilter::try_from_default_env()
+                .or_else(|_| EnvFilter::try_new(default_level))
+                .unwrap(),
+        )
+        .with_ansi(stderr_with_ansi)
+        .with_writer(std::io::stderr)
+        .try_init();
+
     let (codex_wrapper, event, ctrl_c) = codex_wrapper::init_codex(config).await?;
     let codex = Arc::new(codex_wrapper);
     info!("Codex initialized with event: {event:?}");
diff --git a/codex-rs/tui/src/lib.rs b/codex-rs/tui/src/lib.rs
index 4c4f4e91..0117135b 100644
--- a/codex-rs/tui/src/lib.rs
+++ b/codex-rs/tui/src/lib.rs
@@ -114,7 +114,7 @@ pub fn run_main(cli: Cli) -> std::io::Result<()> {
     // modal. The flag is shown when the current working directory is *not*
     // inside a Git repository **and** the user did *not* pass the
     // `--allow-no-git-exec` flag.
-    let show_git_warning = !cli.skip_git_repo_check && !is_inside_git_repo();
+    let show_git_warning = !cli.skip_git_repo_check && !is_inside_git_repo(&config);
 
     try_run_ratatui_app(cli, config, show_git_warning, log_rx);
     Ok(())