diff --git a/.changeset/verify-express5-node24.md b/.changeset/verify-express5-node24.md
new file mode 100644
index 0000000..a74490d
--- /dev/null
+++ b/.changeset/verify-express5-node24.md
@@ -0,0 +1,5 @@
+---
+"seamless-cli": patch
+---
+
+Fix the conformance harness (`seamless verify --local`) failing to build after the ecosystem moved to Express 5 on Node 24. The verify adapter app pinned `express@^4`, but `@seamless-auth/express` now requires `express@>=5` as a peer, so installing the locally-built SDK tarball aborted with an `ERESOLVE` peer conflict and the Docker build failed. The adapter now depends on `express@^5.1.0` (and `@seamless-auth/express@^0.8.0`), and the verify Docker images are bumped from `node:20` to `node:24` to match the ecosystem's supported runtime.
diff --git a/verify/adapter-app/Dockerfile b/verify/adapter-app/Dockerfile
index df40f72..f485f16 100644
--- a/verify/adapter-app/Dockerfile
+++ b/verify/adapter-app/Dockerfile
@@ -1,4 +1,4 @@
-FROM node:20-alpine
+FROM node:24-alpine
 WORKDIR /app
 RUN apk add --no-cache curl
 COPY package.json ./
diff --git a/verify/adapter-app/package.json b/verify/adapter-app/package.json
index ce0e884..55367fe 100644
--- a/verify/adapter-app/package.json
+++ b/verify/adapter-app/package.json
@@ -5,9 +5,9 @@
   "type": "module",
   "description": "Minimal adopter backend for the conformance harness — real @seamless-auth/express with a capture transport.",
   "dependencies": {
-    "@seamless-auth/express": "^0.6.0",
+    "@seamless-auth/express": "^0.8.0",
     "cookie-parser": "^1.4.6",
     "cors": "^2.8.5",
-    "express": "^4.19.2"
+    "express": "^5.1.0"
   }
 }
diff --git a/verify/docker-compose.verify.yml b/verify/docker-compose.verify.yml
index 9c89633..970cb62 100644
--- a/verify/docker-compose.verify.yml
+++ b/verify/docker-compose.verify.yml
@@ -123,7 +123,7 @@ services:
       additional_contexts:
         sdk: ./react-vendor
       dockerfile_inline: |
-        FROM node:20-slim AS builder
+        FROM node:24-slim AS builder
         WORKDIR /app
         COPY package.json package-lock.json ./
         RUN npm ci