Add email verification for email/password signups

New email/password accounts must verify before signing in. Social login
users (Google, Discord) are unaffected. Existing users are grandfathered
via an idempotent migration. Adds a /check-email interstitial with a
resend button, and a --success CSS token for consistent styling.

Closes #343

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/app.css

@@ -28,6 +28,7 @@
   --color-accent: var(--accent);
   --color-accent-foreground: var(--accent-foreground);
   --color-destructive: var(--destructive);
+  --color-success: var(--success);
   --color-border: var(--border);
   --color-input: var(--input);
   --color-ring: var(--ring);
@@ -72,6 +73,7 @@ html {
   --accent: #2ce1c1;
   --accent-foreground: #14171e;
   --destructive: oklch(0.65 0.22 25);
+  --success: oklch(0.65 0.20 145);
   --border: rgb(255 255 255 / 10%);
   --input: rgb(255 255 255 / 12%);
   --ring: #adf661;

app/lib/auth.server.ts

@@ -94,6 +94,19 @@ export const auth = betterAuth({
       });
     },
   },
+  emailVerification: {
+    sendOnSignUp: true,
+    requireEmailVerification: true,
+    autoSignInAfterVerification: true,
+    sendVerificationEmail: async ({ user, url }) => {
+      await resend.emails.send({
+        from: "Brackt <noreply@brackt.com>",
+        to: user.email,
+        subject: "Verify your Brackt email",
+        html: `<p>Thanks for signing up for Brackt!</p><p>Click the link below to verify your email address. This link expires in 24 hours.</p><p><a href="${url}">Verify my email</a></p><p>Or copy this link: ${url}</p>`,
+      });
+    },
+  },
   socialProviders: {
     ...googleProvider,
     ...discordProvider,

app/routes.ts

@@ -57,6 +57,7 @@ export default [
   route("api/seasons/:seasonId/draft", "routes/api/seasons.$seasonId.draft.ts"),
   route("login", "routes/login.tsx"),
   route("register", "routes/register.tsx"),
+  route("check-email", "routes/check-email.tsx"),
   route("forgot-password", "routes/forgot-password.tsx"),
   route("reset-password", "routes/reset-password.tsx"),
   route("user-profile", "routes/user-profile.tsx"),

app/routes/__tests__/check-email.test.ts

@@ -0,0 +1,32 @@
+import { describe, it, expect } from "vitest";
+import { safeRedirectTo } from "../check-email";
+
+describe("safeRedirectTo", () => {
+  it("returns / for null", () => {
+    expect(safeRedirectTo(null)).toBe("/");
+  });
+
+  it("returns / for empty string", () => {
+    expect(safeRedirectTo("")).toBe("/");
+  });
+
+  it("allows a root-relative path", () => {
+    expect(safeRedirectTo("/dashboard")).toBe("/dashboard");
+  });
+
+  it("allows a nested path", () => {
+    expect(safeRedirectTo("/leagues/123/draft/456")).toBe("/leagues/123/draft/456");
+  });
+
+  it("rejects an absolute URL", () => {
+    expect(safeRedirectTo("https://evil.com")).toBe("/");
+  });
+
+  it("rejects a protocol-relative URL", () => {
+    expect(safeRedirectTo("//evil.com")).toBe("/");
+  });
+
+  it("rejects a path starting with //", () => {
+    expect(safeRedirectTo("//not-a-host")).toBe("/");
+  });
+});

app/routes/check-email.tsx

@@ -0,0 +1,89 @@
+import { useState } from "react";
+import { Link, redirect, useLoaderData } from "react-router";
+import { authClient } from "~/lib/auth-client";
+import { Button } from "~/components/ui/button";
+import { Card, CardContent, CardHeader, CardTitle, CardDescription } from "~/components/ui/card";
+import type { Route } from "./+types/check-email";
+
+export function meta(): Route.MetaDescriptors {
+  return [{ title: "Check Your Email - Brackt" }];
+}
+
+export function safeRedirectTo(value: string | null): string {
+  if (!value) return "/";
+  return value.startsWith("/") && !value.startsWith("//") ? value : "/";
+}
+
+export async function loader(args: Route.LoaderArgs) {
+  const url = new URL(args.request.url);
+  const email = url.searchParams.get("email");
+  if (!email) return redirect("/register");
+  return {
+    email,
+    redirectTo: safeRedirectTo(url.searchParams.get("redirectTo")),
+  };
+}
+
+type ResendState = "idle" | "sending" | "sent" | "error";
+
+export default function CheckEmailPage() {
+  const { email, redirectTo } = useLoaderData<typeof loader>();
+  const [resendState, setResendState] = useState<ResendState>("idle");
+  const [resendError, setResendError] = useState<string | null>(null);
+
+  async function handleResend() {
+    setResendState("sending");
+    setResendError(null);
+    const { error } = await authClient.sendVerificationEmail({
+      email,
+      callbackURL: redirectTo,
+    });
+    if (error) {
+      setResendState("error");
+      setResendError(error.message ?? "Could not resend. Please try again.");
+    } else {
+      setResendState("sent");
+    }
+  }
+
+  return (
+    <div className="min-h-screen flex items-center justify-center p-4">
+      <Card className="w-full max-w-md">
+        <CardHeader className="space-y-1">
+          <CardTitle className="text-2xl">Check your email</CardTitle>
+          <CardDescription>We sent a verification link to {email}</CardDescription>
+        </CardHeader>
+        <CardContent className="space-y-4">
+          <p className="text-sm text-muted-foreground">
+            Click the link in the email to verify your account and get started. If you
+            don&apos;t see it, check your spam folder.
+          </p>
+
+          <div className="space-y-2">
+            <Button
+              variant="outline"
+              className="w-full"
+              onClick={handleResend}
+              disabled={resendState === "sending"}
+            >
+              {resendState === "sending" ? "Sending…" : "Resend verification email"}
+            </Button>
+            {resendState === "sent" && (
+              <p className="text-sm text-success">Email sent! Check your inbox.</p>
+            )}
+            {resendState === "error" && resendError && (
+              <p className="text-sm text-destructive">{resendError}</p>
+            )}
+          </div>
+
+          <p className="text-center text-sm text-muted-foreground">
+            Wrong account?{" "}
+            <Link to="/login" className="underline">
+              Sign in
+            </Link>
+          </p>
+        </CardContent>
+      </Card>
+    </div>
+  );
+}

app/routes/register.tsx

@@ -52,8 +52,8 @@ export default function RegisterPage() {
       setError(signUpError.message ?? "Registration failed. Please try again.");
       setLoading(false);
     } else {
-      // BetterAuth redirects via callbackURL; fallback in case it doesn't fire
-      window.location.href = redirectTo;
+      const params = new URLSearchParams({ email, redirectTo });
+      window.location.href = `/check-email?${params.toString()}`;
     }
   }
 

scripts/migrate.mjs

@@ -102,6 +102,18 @@ async function convertForeignKeys(sql) {
     WHERE clerk_id IS NOT NULL
       AND email_verified = false
   `;
+
+  // Grandfather pre-enforcement BetterAuth signups: they have no clerk_id and
+  // registered before email verification was required.
+  const grandfatherResult = await sql`
+    UPDATE users
+    SET email_verified = true
+    WHERE email_verified = false
+      AND clerk_id IS NULL
+  `;
+  if (grandfatherResult.count > 0) {
+    console.log(`  grandfathered ${grandfatherResult.count} pre-enforcement email/password users`);
+  }
 }
 
 async function importClerkOAuthAccounts(sql, secretKey) {