diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index f871b94..ca25bf3 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,6 +1,13 @@
 name: Lint and Test
 
-on: [push]
+permissions: {}
+
+on:
+  push:
+    branches: ['**']
+  schedule:
+    # check the implementation details on Thursdays; 3 days before test suites
+    - cron: 0 5 * * 4
 
 jobs:
   lint:
@@ -11,6 +18,8 @@ jobs:
         node-version: [20.x]
     steps:
       - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v4
         with:
@@ -27,6 +36,8 @@ jobs:
         node-version: [20.x]
     steps:
       - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v4
         with:
diff --git a/lib/main.js b/lib/main.js
index 389d1c6..8145269 100644
--- a/lib/main.js
+++ b/lib/main.js
@@ -7,6 +7,8 @@
 import {Implementation} from './Implementation.js';
 import {implementerFiles} from '../implementations/index.js';
 
+export const rawImplementations = implementerFiles;
+
 const keyValues = implementerFiles.map(
   implementation => [implementation.name, new Implementation(implementation)]);
 
diff --git a/package.json b/package.json
index 25756f1..8fa245d 100644
--- a/package.json
+++ b/package.json
@@ -35,6 +35,7 @@
   },
   "devDependencies": {
     "chai": "^4.3.3",
+    "chai-datetime": "^1.8.1",
     "cross-env": "^7.0.3",
     "eslint": "^8.19.0",
     "eslint-config-digitalbazaar": "^4.0.1",
diff --git a/test/implementations.spec.js b/test/implementations.spec.js
index 6ab86d2..f6170af 100644
--- a/test/implementations.spec.js
+++ b/test/implementations.spec.js
@@ -5,9 +5,11 @@
  */
 
 import chai from 'chai';
+import chaiDateTime from 'chai-datetime';
 const should = chai.should();
+chai.use(chaiDateTime);
 
-import {allImplementations} from '../lib/main.js';
+import {allImplementations, rawImplementations} from '../lib/main.js';
 
 describe('Loading implementations', () => {
   it('should result in no errors.', async () => {
@@ -31,7 +33,7 @@ describe('Loading implementations', () => {
             });
           });
 
-        verifiers.filter(isDidKeyFilter)
+        verifiers?.filter(isDidKeyFilter)
           .map(({settings: {id}}, index) => {
             describe(`verifier[${index}].id`, () => {
               it('should not specify a fragment', () => {
@@ -42,4 +44,26 @@ describe('Loading implementations', () => {
       });
     });
   });
+
+  describe('Implementations using ZCAPs', () => {
+    rawImplementations.forEach(implementation => {
+      Object.keys(implementation)
+        .filter(key => Array.isArray(implementation[key]))
+        .forEach(implementationType => {
+          describe(`${implementation.name} - ${implementationType}`, () => {
+            implementation[implementationType]
+              ?.filter(({zcap}) => zcap?.capability)
+              .forEach(issuer => {
+                it(`ZCAP should not be expired for ${issuer.id}`, () => {
+                  const expiration = JSON.parse(issuer.zcap.capability).expires;
+                  const today = new Date();
+                  const nextMonth = new Date(
+                    today.getFullYear(), today.getMonth() + 1, today.getDate());
+                  chai.expect(new Date(expiration)).to.be.afterDate(nextMonth);
+                });
+              });
+          });
+        });
+    });
+  });
 });