diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..78e863f
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,20 @@
+# Supabase — create project at supabase.com
+NEXT_PUBLIC_SUPABASE_URL=https://your-project.supabase.co
+NEXT_PUBLIC_SUPABASE_ANON_KEY=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
+SUPABASE_SERVICE_ROLE_KEY=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
+
+# NextAuth
+NEXTAUTH_URL=http://localhost:3000
+NEXTAUTH_SECRET=your_nextauth_secret_min_32_chars
+
+# GitHub OAuth App — create at github.com/settings/applications/new
+GITHUB_ID=your_github_oauth_app_client_id
+GITHUB_SECRET=your_github_oauth_app_client_secret
+GITLAB_ID=your_gitlab_application_id
+GITLAB_SECRET=your_gitlab_application_secret
+# Second callback URL to register in your GitHub OAuth App settings:
+# {NEXTAUTH_URL}/api/auth/link-github/callback
+
+# 32-byte hex string for AES-256-GCM token encryption
+# Generate with: node -e "console.log(require('crypto').randomBytes(32).toString('hex'))"
+ENCRYPTION_KEY=
diff --git a/src/app/page.tsx b/src/app/page.tsx
index cb51474..e7430ca 100644
--- a/src/app/page.tsx
+++ b/src/app/page.tsx
@@ -18,13 +18,19 @@ export default async function HomePage() {
           Open-source developer productivity dashboard. Track coding habits,
           visualize GitHub contributions, and hit your goals.
         </p>
-        <div className="flex gap-4 justify-center">
+        <div className="flex flex-col gap-4 justify-center items-center">
           <Link
             href="/api/auth/signin/github?callbackUrl=/dashboard"
             className="bg-white text-slate-900 px-6 py-3 rounded-lg font-semibold hover:bg-slate-100 transition"
           >
             Sign in with GitHub
           </Link>
+          <Link
+            href="/api/auth/signin/gitlab?callbackUrl=/dashboard"
+            className="bg-[var(--accent)] text-[var(--accent-foreground)] px-6 py-3 rounded-lg font-semibold hover:opacity-90 transition"
+          >
+            Sign in with GitLab
+          </Link>
           <a
             href="https://github.com/Priyanshu-byte-coder/devtrack"
             target="_blank"
diff --git a/src/lib/auth.ts b/src/lib/auth.ts
index fb3f421..4fb8c8d 100644
--- a/src/lib/auth.ts
+++ b/src/lib/auth.ts
@@ -1,5 +1,6 @@
 import { type NextAuthOptions } from "next-auth";
 import GitHubProvider from "next-auth/providers/github";
+import GitLabProvider from "next-auth/providers/gitlab";
 import { supabaseAdmin } from "./supabase";
 
 const SESSION_MAX_AGE = 30 * 24 * 60 * 60;
@@ -15,6 +16,13 @@ export const authOptions: NextAuthOptions = {
         params: { scope: "read:user user:email repo" },
       },
     }),
+    GitLabProvider({
+      clientId: process.env.GITLAB_ID ?? "",
+      clientSecret: process.env.GITLAB_SECRET ?? "",
+      authorization: {
+        params: { scope: "read_user api" },
+      },
+    }),
   ],
   session: {
     strategy: "jwt",
@@ -51,15 +59,34 @@ export const authOptions: NextAuthOptions = {
           { onConflict: "github_id" }
         );
       }
+      if (account?.provider === "gitlab" && profile) {
+        const p = profile as { id: number; username: string; email: string };
+        await supabaseAdmin.from("users").upsert(
+          {
+            email: p.email,
+            gitlab_id: String(p.id),
+            gitlab_login: p.username,
+            updated_at: new Date().toISOString(),
+          },
+          { onConflict: "gitlab_id" }
+        );
+      }
       return true;
     },
     async jwt({ token, account, profile }) {
-      if (account?.access_token) token.accessToken = account.access_token;
-      if (profile) {
+      if (account?.provider === "github" && account.access_token)
+        token.accessToken = account.access_token;
+      if (account?.provider === "github" && profile) {
         const p = profile as { id: number; login: string };
         token.githubId = String(p.id);
         token.githubLogin = p.login;
       }
+      if (account?.provider === "gitlab" && profile) {
+        const p = profile as { id: number; username: string };
+        token.gitlabToken = account.access_token;
+        token.gitlabId = String(p.id);
+        token.gitlabLogin = p.username;
+      }
       return token;
     },
     async session({ session, token }) {
@@ -69,6 +96,12 @@ export const authOptions: NextAuthOptions = {
         session.githubId = token.githubId;
       if (typeof token.githubLogin === "string")
         session.githubLogin = token.githubLogin;
+      if (typeof token.gitlabToken === "string")
+        session.gitlabToken = token.gitlabToken;
+      if (typeof token.gitlabId === "string")
+        session.gitlabId = token.gitlabId;
+      if (typeof token.gitlabLogin === "string")
+        session.gitlabLogin = token.gitlabLogin;
       return session;
     },
   },
diff --git a/src/types/next-auth.d.ts b/src/types/next-auth.d.ts
index a1b4776..776df80 100644
--- a/src/types/next-auth.d.ts
+++ b/src/types/next-auth.d.ts
@@ -5,6 +5,9 @@ declare module "next-auth" {
     accessToken?: string;
     githubId?: string;
     githubLogin?: string;
+    gitlabToken?: string;
+    gitlabId?: string;
+    gitlabLogin?: string;
     user?: DefaultSession["user"];
   }
 }
@@ -14,5 +17,8 @@ declare module "next-auth/jwt" {
     accessToken?: string;
     githubId?: string;
     githubLogin?: string;
+    gitlabToken?: string;
+    gitlabId?: string;
+    gitlabLogin?: string;
   }
 }
diff --git a/supabase/migrations/20260520000000_add_gitlab_columns.sql b/supabase/migrations/20260520000000_add_gitlab_columns.sql
new file mode 100644
index 0000000..33f4378
--- /dev/null
+++ b/supabase/migrations/20260520000000_add_gitlab_columns.sql
@@ -0,0 +1,4 @@
+sqlALTER TABLE users ADD COLUMN IF NOT EXISTS gitlab_id text UNIQUE;
+ALTER TABLE users ADD COLUMN IF NOT EXISTS gitlab_login text;
+ALTER TABLE users ALTER COLUMN github_id DROP NOT NULL;
+ALTER TABLE users ALTER COLUMN github_login DROP NOT NULL;
diff --git a/supabase/schema.sql b/supabase/schema.sql
index e807e46..8866879 100644
--- a/supabase/schema.sql
+++ b/supabase/schema.sql
@@ -2,8 +2,10 @@
 
 create table if not exists users (
   id           text primary key default gen_random_uuid()::text,
-  github_id    text unique not null,
-  github_login text not null,
+  github_id    text unique,
+  github_login text,
+  gitlab_id    text unique,
+  gitlab_login text,
   created_at   timestamptz default now(),
   updated_at   timestamptz default now()
 );