diff --git a/docker/Dockerfile b/docker/Dockerfile
index 36526c2..a2d4600 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,4 +1,4 @@
-FROM rust:1.85
+FROM rust:1.88
 
 RUN rustup update
 RUN rustup component add clippy
diff --git a/lib/Cargo.toml b/lib/Cargo.toml
index f41c00d..85d4841 100644
--- a/lib/Cargo.toml
+++ b/lib/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "rs-firebase-admin-sdk"
-version = "4.1.0"
-rust-version = "1.85"
+version = "4.1.1"
+rust-version = "1.88"
 edition = "2024"
 authors = ["Kostas Petrikas"]
 categories = ["authentication", "api-bindings", "asynchronous"]
diff --git a/lib/src/credentials/mod.rs b/lib/src/credentials/mod.rs
index f7fa1dc..50c967f 100644
--- a/lib/src/credentials/mod.rs
+++ b/lib/src/credentials/mod.rs
@@ -7,6 +7,7 @@ use google_cloud_auth::credentials::{CacheableResource, Credentials};
 use headers::HeaderMapExt;
 use headers::{Header, HeaderName, HeaderValue};
 use http::{Extensions, HeaderMap};
+use std::env::var;
 
 #[derive(thiserror::Error, Debug, Clone)]
 #[error("Failed to extract GCP credentials")]
@@ -49,6 +50,10 @@ impl Header for GoogleUserProject {
 pub(crate) async fn get_project_id(
     creds: &Credentials,
 ) -> Result<String, Report<GCPCredentialsError>> {
+    if let Ok(project_id) = var("GOOGLE_CLOUD_PROJECT") {
+        return Ok(project_id);
+    }
+
     let headers = get_headers(creds).await?;
 
     let user_project: GoogleUserProject = headers