diff --git a/package.json b/package.json
index 4975b68..f1f8732 100644
--- a/package.json
+++ b/package.json
@@ -21,6 +21,7 @@
   "scripts": {
     "build": "tsup src/index.ts; tsup src/daemon/index.ts -d dist/daemon; tsup src/client.ts -d dist/client",
     "build:client": "tsup src/client.ts -d dist/client",
+    "test": "TS_NODE_TRANSPILE_ONLY=1 node -r ts-node/register --test tests/*.test.ts",
     "prisma:generate": "npx prisma generate",
     "prisma:migrate": "npx prisma migrate deploy",
     "prisma:create": "npx prisma db push --preview-feature",
diff --git a/src/daemon/lib/acl/index.ts b/src/daemon/lib/acl/index.ts
index a3f17ab..d693e72 100644
--- a/src/daemon/lib/acl/index.ts
+++ b/src/daemon/lib/acl/index.ts
@@ -1,37 +1,11 @@
 import { NostrEvent, NIP46Method } from '@nostr-dev-kit/ndk';
 import prisma from '../../../db.js';
+import { liveWhere } from './lifecycle.js';
 
-/**
- * "Is this grant valid right now?" — the single lifecycle predicate, used
- * identically at redeem time (Backend.validateToken) and sign time
- * (checkIfPubkeyAllowed). Both Token and SigningCondition carry `revokedAt`
- * + `expiresAt`, so one shape governs token grants and manual overrides.
- *
- * The original #24 bug was possible because redeem-time checked expiry and
- * sign-time didn't — two definitions of "valid" that drifted. Defining it
- * once makes them impossible to disagree. See aiolabs/nsecbunkerd#25.
- */
-export function grantIsLive(
-    grant: { revokedAt?: Date | null; expiresAt?: Date | null },
-    now: Date = new Date(),
-): boolean {
-    if (grant.revokedAt) return false;
-    if (grant.expiresAt && grant.expiresAt.getTime() <= now.getTime()) return false;
-    return true;
-}
-
-/**
- * Prisma `where` fragment selecting only lifecycle-live rows (not revoked,
- * not past expiry) — grantIsLive expressed in SQL so the live filter happens
- * in the query, not in app code after the fact. `now` is threaded in so a
- * single request evaluates every row against one clock reading.
- */
-function liveWhere(now: Date) {
-    return {
-        revokedAt: null,
-        OR: [{ expiresAt: null }, { expiresAt: { gt: now } }],
-    };
-}
+// Re-export the single lifecycle predicate so callers (e.g.
+// Backend.validateToken) import it from the ACL module. The implementation
+// lives in ./lifecycle.ts so it can be unit-tested without a database.
+export { grantIsLive } from './lifecycle.js';
 
 /**
  * Layered authorization check. Order matters (denials beat grants):
diff --git a/src/daemon/lib/acl/lifecycle.ts b/src/daemon/lib/acl/lifecycle.ts
new file mode 100644
index 0000000..783dd84
--- /dev/null
+++ b/src/daemon/lib/acl/lifecycle.ts
@@ -0,0 +1,40 @@
+/**
+ * Pure grant-lifecycle logic, extracted from the ACL so it can be unit-tested
+ * without a database and reused verbatim at redeem time and sign time.
+ *
+ * The original #24 bug was possible because redeem-time checked expiry and
+ * sign-time didn't — two definitions of "valid" that drifted. Defining "is
+ * this grant valid right now?" exactly once makes them impossible to disagree.
+ * See aiolabs/nsecbunkerd#25.
+ */
+
+/** The lifecycle fields every grant (Token, SigningCondition) carries. */
+export type Lifecycle = {
+    revokedAt?: Date | null;
+    expiresAt?: Date | null;
+};
+
+/**
+ * "Is this grant valid right now?" — the single lifecycle predicate. A grant
+ * is live iff it has not been revoked and its expiry (if any) is still in the
+ * future. Expiry is treated as exclusive at the boundary: a grant whose
+ * `expiresAt` equals `now` is already dead.
+ */
+export function grantIsLive(grant: Lifecycle, now: Date = new Date()): boolean {
+    if (grant.revokedAt) return false;
+    if (grant.expiresAt && grant.expiresAt.getTime() <= now.getTime()) return false;
+    return true;
+}
+
+/**
+ * `grantIsLive` expressed as a Prisma `where` fragment, so the live filter
+ * runs in the query rather than in app code after the fetch. `now` is threaded
+ * in explicitly so a single request evaluates every row against one clock
+ * reading. Kept in lockstep with `grantIsLive` (see lifecycle.test.ts).
+ */
+export function liveWhere(now: Date) {
+    return {
+        revokedAt: null,
+        OR: [{ expiresAt: null }, { expiresAt: { gt: now } }],
+    };
+}
diff --git a/tests/lifecycle.test.ts b/tests/lifecycle.test.ts
new file mode 100644
index 0000000..4bbe5f1
--- /dev/null
+++ b/tests/lifecycle.test.ts
@@ -0,0 +1,44 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { grantIsLive, liveWhere } from '../src/daemon/lib/acl/lifecycle';
+
+// Fixed reference clock so the assertions don't depend on wall time.
+const now = new Date('2026-06-19T12:00:00.000Z');
+const past = new Date(now.getTime() - 60_000);
+const future = new Date(now.getTime() + 60_000);
+
+test('grantIsLive: no revoke, no expiry -> live', () => {
+    assert.equal(grantIsLive({}, now), true);
+    assert.equal(grantIsLive({ revokedAt: null, expiresAt: null }, now), true);
+});
+
+test('grantIsLive: future expiry -> live', () => {
+    assert.equal(grantIsLive({ expiresAt: future }, now), true);
+});
+
+test('grantIsLive: past expiry -> dead (the #24 case the old code missed at sign time)', () => {
+    assert.equal(grantIsLive({ expiresAt: past }, now), false);
+});
+
+test('grantIsLive: expiry exactly now -> dead (boundary is exclusive)', () => {
+    assert.equal(grantIsLive({ expiresAt: new Date(now.getTime()) }, now), false);
+});
+
+test('grantIsLive: revoked -> dead even with a future expiry (revoke wins)', () => {
+    assert.equal(grantIsLive({ revokedAt: past, expiresAt: future }, now), false);
+});
+
+test('grantIsLive: defaults now to the current time', () => {
+    assert.equal(grantIsLive({ expiresAt: new Date(Date.now() + 3_600_000) }), true);
+    assert.equal(grantIsLive({ expiresAt: new Date(Date.now() - 3_600_000) }), false);
+});
+
+// liveWhere is the SQL mirror of grantIsLive; pin its shape so the two
+// can't silently drift (a drift would re-open the redeem-vs-sign gap #25
+// exists to close).
+test('liveWhere: mirrors grantIsLive as a prisma where-fragment', () => {
+    assert.deepEqual(liveWhere(now), {
+        revokedAt: null,
+        OR: [{ expiresAt: null }, { expiresAt: { gt: now } }],
+    });
+});