feat(domain): withdraw a registration → INGETROKKEN via POST /registrations/{id}/withdraw (refs #12 )

Add the Ingetrokken terminal status, Registration.Withdraw() (open-only, idempotent), the WithdrawRegistration handler, and the domain endpoint. Cancelling the running Flowable process (so the case leaves the werkbak) and the owner-scoped BFF/self-service action are follow-up sub-slices (S-11b/S-11c). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
test(domain): a citizen can withdraw an open registration → INGETROKKEN (refs #12 )
2026-07-16 10:53:31 +02:00 · 2026-07-16 10:43:22 +02:00
31 changed files with 50 additions and 934 deletions
--- a/apps/self-service/src/app/registration/registration-page.html
+++ b/apps/self-service/src/app/registration/registration-page.html
@@ -3,29 +3,9 @@
    <utrecht-heading-1>Zelfservice — BIG-registratie</utrecht-heading-1>

    @if (submitted()) {
-      @if (withdrawn()) {
-        <p utrecht-paragraph role="status">
-          Uw registratie met referentie {{ reference() }} is ingetrokken.
-        </p>
-      } @else {
-        <p utrecht-paragraph role="status">
-          Uw registratie is ontvangen. Referentie: {{ reference() }}.
-        </p>
-        @if (withdrawFailed()) {
-          <p utrecht-paragraph role="alert">
-            Het intrekken van uw registratie is niet gelukt. Probeer het opnieuw.
-          </p>
-        }
-        <button
-          utrecht-button
-          appearance="secondary-action-button"
-          type="button"
-          [disabled]="withdrawing()"
-          (click)="withdraw()"
-        >
-          Trek aanvraag in
-        </button>
-      }
+      <p utrecht-paragraph role="status">
+        Uw registratie is ontvangen. Referentie: {{ reference() }}.
+      </p>
    } @else {
      <p utrecht-paragraph>U bent ingelogd met BSN {{ bsn() }}.</p>
      @if (failed()) {
--- a/apps/self-service/src/app/registration/registration-page.spec.ts
+++ b/apps/self-service/src/app/registration/registration-page.spec.ts
@@ -17,22 +17,12 @@ class FakeAuth extends AuthService {
  }
 }

-function providers(
-  post = vi.fn().mockReturnValue(of({ registrationId: 'reg-9', status: 'Ingediend' })),
-  withdraw = vi.fn().mockReturnValue(of(undefined)),
-) {
+function providers(post = vi.fn().mockReturnValue(of({ registrationId: 'reg-9', status: 'Ingediend' }))) {
  return {
    post,
-    withdraw,
    providers: [
      { provide: AuthService, useClass: FakeAuth },
-      {
-        provide: BffApiV1Service,
-        useValue: {
-          postSelfServiceRegistrations: post,
-          postSelfServiceRegistrationsIdWithdraw: withdraw,
-        },
-      },
+      { provide: BffApiV1Service, useValue: { postSelfServiceRegistrations: post } },
    ],
  };
 }
@@ -66,36 +56,6 @@ describe('RegistrationPage', () => {
    expect(screen.getByRole('button', { name: /indienen/i })).toBeTruthy();
  });

-  it('offers to withdraw after submitting, and withdrawing confirms', async () => {
-    const { withdraw, providers: p } = providers();
-    await render(RegistrationPage, { providers: p });
-
-    fireEvent.click(screen.getByRole('button', { name: /indienen/i }));
-    await screen.findByText(/ontvangen/i);
-
-    fireEvent.click(await screen.findByRole('button', { name: /trek aanvraag in/i }));
-
-    // The withdrawal is keyed by the reference the submit returned, and the page confirms it.
-    expect(withdraw).toHaveBeenCalledWith('reg-9');
-    expect(await screen.findByText(/ingetrokken/i)).toBeTruthy();
-  });
-
-  it('surfaces a withdraw failure and keeps the action available', async () => {
-    const { providers: p } = providers(
-      vi.fn().mockReturnValue(of({ registrationId: 'reg-9', status: 'Ingediend' })),
-      vi.fn().mockReturnValue(throwError(() => new Error('withdraw rejected'))),
-    );
-    await render(RegistrationPage, { providers: p });
-
-    fireEvent.click(screen.getByRole('button', { name: /indienen/i }));
-    await screen.findByText(/ontvangen/i);
-    fireEvent.click(await screen.findByRole('button', { name: /trek aanvraag in/i }));
-
-    expect(await screen.findByRole('alert')).toBeTruthy();
-    expect(screen.queryByText(/is ingetrokken/i)).toBeNull();
-    expect(screen.getByRole('button', { name: /trek aanvraag in/i })).toBeTruthy();
-  });
-
  it('has no WCAG 2.1 AA violations on the submit page', async () => {
    // The portal is Dutch; the real index.html sets lang. Set it here so the document-level
    // html-has-lang rule reflects the app, not the bare jsdom document.
--- a/apps/self-service/src/app/registration/registration-page.ts
+++ b/apps/self-service/src/app/registration/registration-page.ts
@@ -6,8 +6,7 @@ import { UtrechtComponentsModule } from 'ui';
 /**
 * The self-service submit page: a signed-in zorgprofessional confirms and submits their BIG
 * registration. The bsn comes from the DigiD token (not a form field), so this is a confirm-and-
- * submit flow that posts to the BFF and shows the returned reference (ADR-0010; S-08c). After
- * submitting they can withdraw it — "trek aanvraag in" — keyed by that reference (S-11c).
+ * submit flow that posts to the BFF and shows the returned reference (ADR-0010; S-08c).
 */
@Component({
  selector: 'app-registration-page',
@@ -23,9 +22,6 @@ export class RegistrationPage {
  protected readonly reference = signal<string | undefined>(undefined);
  protected readonly submitted = signal(false);
  protected readonly failed = signal(false);
-  protected readonly withdrawing = signal(false);
-  protected readonly withdrawn = signal(false);
-  protected readonly withdrawFailed = signal(false);

  submit(): void {
    this.submitting.set(true);
@@ -43,24 +39,4 @@ export class RegistrationPage {
      },
    });
  }
-
-  withdraw(): void {
-    const reference = this.reference();
-    if (!reference) {
-      return;
-    }
-    this.withdrawing.set(true);
-    this.withdrawFailed.set(false);
-    this.bff.postSelfServiceRegistrationsIdWithdraw(reference).subscribe({
-      next: () => {
-        this.withdrawn.set(true);
-        this.withdrawing.set(false);
-      },
-      // Surface the failure instead of swallowing it: keep the action so the user can retry.
-      error: () => {
-        this.withdrawFailed.set(true);
-        this.withdrawing.set(false);
-      },
-    });
-  }
 }
--- a/docs/architecture/adr-0014-withdrawal-cancels-the-process.md
+++ b/docs/architecture/adr-0014-withdrawal-cancels-the-process.md
@@ -1,72 +0,0 @@
-# ADR-0014: Withdrawal cancels the registratie process via a BPMN message event
-
- **Status:** Accepted
- **Date:** 2026-07-16
- **Deciders:** Respellion engineering
- **Relates to:** S-11 (#12); builds on ADR-0009 (external-task worker / Workflow Client), ADR-0013
-  (behandel-portal wiring, the Beoordelen user task)
-
-## Context
-
-S-11 lets a zorgprofessional withdraw a still-open registration ("trek aanvraag in"). S-11a already
-advances the aggregate to INGETROKKEN (domain state). But the registratie process is still running in
-Flowable — parked at the `Beoordelen` user task — so without a second step the withdrawn registration
-would linger as work for a behandelaar. The withdrawal must also **cancel the running process**.
-
-Two questions shape this sub-slice.
-
-1. **How does the case get cancelled — in code, or in the BPMN model?**
-2. **How does a withdrawal correlate to the right running process instance?**
-
-## Decision
-
-**The BPMN models the cancellation as an interrupting message boundary event on the `Beoordelen`
-task; the Workflow Client correlates a `RegistratieIngetrokken` message to the task's execution.**
-
- **Modelled in BPMN, not deleted from code.** The `Beoordelen` user task carries an interrupting
-  message boundary event (`RegistratieIngetrokken`) that routes to a dedicated "Registratie
-  ingetrokken" end event. The process's own model says *how* a withdrawal ends it — the Workflow
-  Client only delivers the message; it never reaches into Flowable to delete an instance. This keeps
-  the workflow's control flow in the workflow (§8.2) and leaves an audit trail in Flowable history
-  (the process ended via the ingetrokken path, not a raw delete).
- **Correlated by the registration's own process instance.** The aggregate records its Flowable
-  process instance id at submit, so the `WithdrawRegistration` handler correlates directly by that
-  id — no task lookup. The Workflow Client asks Flowable for the execution **subscribed to** the
-  `RegistratieIngetrokken` message in that instance and delivers `messageEventReceived` to it.
-  Targeting the subscribed execution (not the user task's execution — a message boundary event's
-  subscription lives on its own execution) is what makes the correlation land.
- **Best-effort, mirroring the beoordeling.** If no open `Beoordelen` task is found (the process has
-  not yet parked there — the `OpenZaakAanmaken` window — or has already ended), the withdrawal still
-  stands: the aggregate is INGETROKKEN and the werkbak filters it out regardless (S-11b). We complete
-  the domain transition first and cancel the workflow best-effort, exactly as `BeoordeelRegistratie`
-  completes its task best-effort.
-
-## Consequences
-
-**Positive**
-
- The cancellation path is visible in `registratie.bpmn`; the Workflow Client stays the only code
-  that talks to Flowable and does not delete instances behind the model's back.
- Reuses the existing task-query correlation — no new plumbing, no correlation store.
- A withdrawn case leaves the werkbak (its `Beoordelen` task is cancelled), and the werkbak also
-  filters non-open registrations as a belt-and-braces for the brief window before cancellation lands.
-
-**Negative / costs**
-
- A withdrawal raced ahead of the process reaching `Beoordelen` (during `OpenZaakAanmaken`, seconds)
-  finds no task to cancel, so that process instance runs on to `Beoordelen` and parks there with no
-  one to act on it (it is hidden from the werkbak by the status filter). Acceptable for this
-  reference at these volumes; a process-level interrupting event subprocess would close the gap and
-  is an additive follow-up if it matters.
- The Flowable message-correlation REST shape is validated live (verify-stack), not in the
-  Workflow Client's unit tests, which stub the HTTP exchange and assert only the request shape
-  (consistent with ADR-0009).
-
-## Alternatives considered
-
- **Delete the process instance from the Workflow Client** (`DELETE /runtime/process-instances/{id}`)
-  — rejected: it cancels the case but hides the reason from the BPMN model; the "why" lives in code,
-  not the process. The message event keeps the cancellation a first-class part of the workflow.
- **Interrupting message event subprocess at process level** — more robust (correlates anytime,
-  closing the `OpenZaakAanmaken`-race gap), but a heavier BPMN construct; deferred as an additive
-  change if the race proves to matter.
--- a/docs/demo-script.md
+++ b/docs/demo-script.md
@@ -275,26 +275,3 @@ ACL → NRC → event-subscriber → projection → openbaar register shows INGE
 > The full round-trip — DigiD submit → public INGEDIEND → behandelaar goedkeurt in the werkbak →
 > public INGESCHREVEN — is the Playwright happy path (`tests/e2e/registration.spec.ts`), which now
 > drives the behandel portal in place of the old admin endpoint.
-
-## S-11 — Withdrawal: "trek aanvraag in" (#12, ADR-0014)
-
-A zorgprofessional can withdraw their own still-open registration from the self-service portal. The
-withdrawal is owner-scoped (the BFF forwards the DigiD token's bsn; the domain only lets the owner
-withdraw) and cancels the running workflow via a BPMN message event, so the case leaves the
-behandelaar's werkbak.
-
-```text
-# 1. Log in and submit at the self-service portal (http://localhost:8140/, jan-burger / test123),
-#    note the "Referentie" on the confirmation.
-# 2. Click "Trek aanvraag in" → the page confirms the registration is ingetrokken.
-# 3. In the behandel werkbak (http://localhost:8142/, merel-behandelaar) the registration no longer
-#    appears — its Beoordelen task was cancelled.
-```
-
-**The path:** self-service → BFF `POST /self-service/registrations/{id}/withdraw` (DigiD, owner-scoped)
-→ domain sets INGETROKKEN + correlates the `RegistratieIngetrokken` message to the process → the
-interrupting boundary event ends it → the werkbak drops the case.
-
-> DigiD submit → trek aanvraag in → ingetrokken is the Playwright happy path
-> (`tests/e2e/withdrawal.spec.ts`); the owner-scoping + workflow cancellation are covered by the
-> `Een registratie intrekken` acceptance scenarios and the domain live check.
--- a/docs/frontend-decisions.md
+++ b/docs/frontend-decisions.md
@@ -151,19 +151,3 @@ frontend work is the medewerker realm auth and the werkbak/decide page. Wiring r
  to assert the medewerker token attaches to `/behandel/*` (and not to the anonymous openbaar call).
  The full DigiD-submit → behandel-decide → public INGESCHREVEN round-trip is the Playwright happy
  path.
-
-## Self-service withdrawal: "trek aanvraag in" (S-11c, #12)
-
-The submit confirmation grows a **"Trek aanvraag in"** action so a zorgprofessional can withdraw the
-registration they just submitted (`apps/self-service`, on the existing `RegistrationPage`).
-
- **Keyed by the reference, owner-scoped at the BFF.** The button calls the generated
-  `postSelfServiceRegistrationsIdWithdraw(reference)` with the reference the submit returned. The
-  DigiD token (attached by the interceptor) carries the bsn the BFF forwards; the domain only lets
-  the owner withdraw (a mismatch is 404). No extra identity is entered in the UI.
- **Same confirm-and-surface pattern as submit.** A secondary-action button; on success the page
-  switches to an ingetrokken confirmation; a failure is surfaced (`role="alert"`) and the action
-  stays available to retry — mirroring how submit handles its failure rather than swallowing it.
- **Testing.** Component tests (`@testing-library/angular`, mocked BFF) cover the button appearing
-  after submit, the reference being passed, the ingetrokken confirmation, and the failure path; the
-  browser round-trip is `tests/e2e/withdrawal.spec.ts`.
--- a/infra/docker-compose.local.yml
+++ b/infra/docker-compose.local.yml
@@ -17,12 +17,7 @@
 #
 # Port map (host):
 #   8000 OpenZaak · 8001 Open Notificaties · 8080 BFF · 8090 Flowable REST
-#   8100 ACL · 8130 Domain · 8180 Keycloak   (all admin: admin / admin — dev only)
-#   8140 self-service portal · 8141 openbaar register · 8142 behandel portal
-#
-# Portal OIDC on the HOST: browse the portals at their 8140/8141/8142 ports and log in via
-# Keycloak on localhost:8180 (KC_HOSTNAME below pins the issuer there; the BFF still validates
-# in-network via keycloak:8080). Test users are in docs/synthetic-data.md.
+#   8100 ACL · 8180 Keycloak   (all admin: admin / admin — dev only)

 services:

@@ -210,12 +205,6 @@ services:
      KEYCLOAK_ADMIN_PASSWORD: admin
      KC_HEALTH_ENABLED: "true"
      KC_HTTP_ENABLED: "true"
-      # Pin the frontend/issuer URL to the host-published address so a browser on the host and the
-      # tokens it gets both use localhost:8180. KC_HOSTNAME_BACKCHANNEL_DYNAMIC lets in-network
-      # callers (the BFF via keycloak:8080) still resolve token/jwks endpoints to their request host,
-      # so the BFF validates the localhost:8180 issuer while fetching keys over the compose network.
-      KC_HOSTNAME: http://localhost:8180
-      KC_HOSTNAME_BACKCHANNEL_DYNAMIC: "true"
    ports:
      - "8180:8080"
    volumes:
@@ -306,14 +295,6 @@ services:
      context: ../services/bff
      dockerfile: Dockerfile
    image: register-referentie/bff:dev
-    environment:
-      # Reach Keycloak over the compose network for metadata/keys; the discovered issuer is the
-      # host-pinned localhost:8180 (KC_HOSTNAME above), which is what browser tokens carry — so
-      # validation matches without the BFF ever needing to resolve localhost:8180 itself.
-      Keycloak__Authority: http://keycloak:8080/realms/digid
-      Keycloak__MedewerkerAuthority: http://keycloak:8080/realms/medewerker
-      Downstream__Domain__BaseUrl: http://domain:8080/
-      Downstream__Projection__BaseUrl: http://projection-api:8080/
    ports:
      - "8080:8080"
    healthcheck:
@@ -322,39 +303,6 @@ services:
      timeout: 3s
      retries: 5
      start_period: 10s
-    depends_on:
-      domain:
-        condition: service_healthy
-      projection-api:
-        condition: service_healthy
-      keycloak:
-        condition: service_started
-    networks: [cg]
-
-  # ── BIG Domain Service (S-05) ─────────────────────────────────────────────
-  domain:
-    build:
-      context: ../services/domain
-      dockerfile: Dockerfile
-    image: register-referentie/domain:dev
-    environment:
-      Flowable__BaseUrl: http://flowable-rest:8080/flowable-rest/
-      Flowable__Username: rest-admin
-      Flowable__Password: test
-      Acl__BaseUrl: http://acl:8080/
-    ports:
-      - "8130:8080"
-    healthcheck:
-      test: ["CMD", "curl", "-fsS", "http://localhost:8080/health"]
-      interval: 5s
-      timeout: 3s
-      retries: 5
-      start_period: 10s
-    depends_on:
-      acl:
-        condition: service_healthy
-      flowable-init:
-        condition: service_completed_successfully
    networks: [cg]

  # ── Read projection (S-06) ────────────────────────────────────────────────
@@ -380,10 +328,6 @@ services:
    image: register-referentie/event-subscriber:dev
    environment:
      ConnectionStrings__Projection: Host=projection-db;Database=projection;Username=projection;Password=projection
-      # The subscriber enriches the projection with each zaak's reference by asking the ACL — the only
-      # code allowed to read ZGW (§8.1, #78). Required: startup throws without it (parity with the
-      # canonical compose).
-      Acl__BaseUrl: http://acl:8080/
      EventSubscriber__Webhook__AuthToken: ${NOTIFICATION_WEBHOOK_TOKEN:-Bearer big-reference-notifications}
    ports:
      - "8110:8080"
@@ -396,8 +340,6 @@ services:
    depends_on:
      projection-db:
        condition: service_healthy
-      acl:
-        condition: service_healthy
    networks: [cg]

  projection-api:
@@ -420,73 +362,6 @@ services:
        condition: service_healthy
    networks: [cg]

-  # ── Portals (S-08/S-09/S-12) ──────────────────────────────────────────────
-  # nginx serves each Angular app and reverse-proxies its endpoint group to the BFF (same-origin).
-  # The images bake config.json with the compose authority (keycloak:8080), which a HOST browser
-  # can't resolve — so here we bind-mount a config.json pointing at the host-published localhost:8180
-  # (matching KC_HOSTNAME). openbaar is anonymous and needs no config.
-  self-service:
-    build:
-      context: ..
-      dockerfile: apps/self-service/Dockerfile
-    image: register-referentie/self-service:dev
-    ports:
-      - "8140:80"
-    volumes:
-      - ./local-config/self-service.config.json:/usr/share/nginx/html/config.json:ro,z
-    healthcheck:
-      test: ["CMD-SHELL", "wget -q -O /dev/null http://127.0.0.1/ || exit 1"]
-      interval: 5s
-      timeout: 3s
-      retries: 5
-      start_period: 10s
-    depends_on:
-      bff:
-        condition: service_healthy
-      keycloak:
-        condition: service_started
-    networks: [cg]
-
-  openbaar:
-    build:
-      context: ..
-      dockerfile: apps/openbaar/Dockerfile
-    image: register-referentie/openbaar:dev
-    ports:
-      - "8141:80"
-    healthcheck:
-      test: ["CMD-SHELL", "wget -q -O /dev/null http://127.0.0.1/ || exit 1"]
-      interval: 5s
-      timeout: 3s
-      retries: 5
-      start_period: 10s
-    depends_on:
-      bff:
-        condition: service_healthy
-    networks: [cg]
-
-  behandel:
-    build:
-      context: ..
-      dockerfile: apps/behandel/Dockerfile
-    image: register-referentie/behandel:dev
-    ports:
-      - "8142:80"
-    volumes:
-      - ./local-config/behandel.config.json:/usr/share/nginx/html/config.json:ro,z
-    healthcheck:
-      test: ["CMD-SHELL", "wget -q -O /dev/null http://127.0.0.1/ || exit 1"]
-      interval: 5s
-      timeout: 3s
-      retries: 5
-      start_period: 10s
-    depends_on:
-      bff:
-        condition: service_healthy
-      keycloak:
-        condition: service_started
-    networks: [cg]
-
 volumes:
  oz-db:
  nrc-db:
--- a/infra/local-config/behandel.config.json
+++ b/infra/local-config/behandel.config.json
@@ -1,3 +0,0 @@
-{
-  "authority": "http://localhost:8180/realms/medewerker"
-}
--- a/infra/local-config/self-service.config.json
+++ b/infra/local-config/self-service.config.json
@@ -1,3 +0,0 @@
-{
-  "authority": "http://localhost:8180/realms/digid"
-}
--- a/infra/run-domain-check.sh
+++ b/infra/run-domain-check.sh
@@ -79,9 +79,9 @@ fl="$(docker ps -q --filter 'name=flowable-rest' | head -1)"
 fl_base="http://$(ip "$fl"):8080/flowable-rest/service"
 reg_id="${loc##*/}"

-# Extracts the Beoordelen task id for a given registration from a Flowable task-query response on
-# stdin. Tolerates an empty/non-JSON body (a transient failure during the poll) by printing nothing.
-task_for_reg() { REG_ID="$1" python3 -c "import os,sys,json
+# Extracts the Beoordelen task id for our registration from a Flowable task-query response on stdin.
+# Tolerates an empty/non-JSON body (a transient failure during the poll) by printing nothing.
+task_for_reg() { REG_ID="$reg_id" python3 -c "import os,sys,json
 try:
    d=json.load(sys.stdin)
 except Exception:
@@ -98,7 +98,7 @@ echo ">> polling Flowable for the Beoordelen user task (werkbak)"
 task_id=""
 for _ in $(seq 1 30); do
  resp="$(flcurl -X POST "$fl_base/query/tasks" -H 'Content-Type: application/json' -d "$query" 2>/dev/null || true)"
-  task_id="$(printf '%s' "$resp" | task_for_reg "$reg_id")"
+  task_id="$(printf '%s' "$resp" | task_for_reg)"
  [ -n "$task_id" ] && break
  sleep 2
 done
@@ -115,46 +115,7 @@ flcurl -X POST "$fl_base/runtime/tasks/$task_id" -H 'Content-Type: application/j

 echo ">> asserting the process finished (no Beoordelen task remains for the registration)"
 resp="$(flcurl -X POST "$fl_base/query/tasks" -H 'Content-Type: application/json' -d "$query")"
-still="$(printf '%s' "$resp" | task_for_reg "$reg_id")"
+still="$(printf '%s' "$resp" | task_for_reg)"
 [ -z "$still" ] || { echo "FAIL — Beoordelen task $still still active after completion" >&2; exit 1; }
 echo "OK — behandelaar claimed and completed the Beoordelen task; the registratie process finished"
-
-# ── S-11: withdrawal. A second registration parks at Beoordelen; the citizen withdraws it via the
-# domain, which delivers the RegistratieIngetrokken message to the task's execution, tripping the
-# BPMN boundary event so the process ends and the Beoordelen task disappears (ADR-0014). ────────────
-echo ">> submitting a second registration to withdraw"
-loc2="$(docker run --rm --network "$net" curlimages/curl:latest \
-  -fsS -D - -o /dev/null -X POST "http://$dom_ip:8080/registrations" \
-  -H 'Content-Type: application/json' -d '{"bsn":"123456782"}' \
-  | sed -n 's/\r$//; s/^[Ll]ocation: //p' | head -1)"
-[ -n "$loc2" ] || { echo "FAIL — second POST /registrations returned no Location" >&2; exit 1; }
-reg_id2="${loc2##*/}"
-echo ">> second registration $reg_id2"
-
-echo ">> polling Flowable for its Beoordelen task"
-task_id2=""
-for _ in $(seq 1 30); do
-  resp="$(flcurl -X POST "$fl_base/query/tasks" -H 'Content-Type: application/json' -d "$query" 2>/dev/null || true)"
-  task_id2="$(printf '%s' "$resp" | task_for_reg "$reg_id2")"
-  [ -n "$task_id2" ] && break
-  sleep 2
-done
-[ -n "$task_id2" ] || { echo "FAIL — no Beoordelen task appeared for registration $reg_id2" >&2; docker logs "$dom" 2>&1 | tail -15 >&2; exit 1; }
-echo ">> Beoordelen task $task_id2 is waiting; withdrawing the registration via the domain"
-
-# Owner-scoped: the withdraw carries the same bsn the registration was submitted with (S-11c).
-docker run --rm --network "$net" curlimages/curl:latest \
-  -fsS -X POST "http://$dom_ip:8080/registrations/$reg_id2/withdraw" \
-  -H 'Content-Type: application/json' -d '{"bsn":"123456782"}' >/dev/null
-
-echo ">> asserting the process was cancelled (no Beoordelen task remains for the registration)"
-gone=""
-for _ in $(seq 1 15); do
-  resp="$(flcurl -X POST "$fl_base/query/tasks" -H 'Content-Type: application/json' -d "$query" 2>/dev/null || true)"
-  still2="$(printf '%s' "$resp" | task_for_reg "$reg_id2")"
-  [ -z "$still2" ] && { gone=1; break; }
-  sleep 2
-done
-[ -n "$gone" ] || { echo "FAIL — Beoordelen task for $reg_id2 still active after withdrawal" >&2; docker logs "$dom" 2>&1 | tail -15 >&2; exit 1; }
-echo "OK — withdrawal cancelled the Beoordelen task; the registratie process ended (ingetrokken)"
 exit 0
--- a/libs/api-client/src/lib/generated/bff-api.ts
+++ b/libs/api-client/src/lib/generated/bff-api.ts
@@ -192,40 +192,6 @@ export class BffApiV1Service {
    );
  }

- postSelfServiceRegistrationsIdWithdraw<TData = void>(id: string, options?: HttpClientBodyOptions): Observable<TData>;
- postSelfServiceRegistrationsIdWithdraw<TData = void>(id: string, options?: HttpClientEventOptions): Observable<HttpEvent<TData>>;
- postSelfServiceRegistrationsIdWithdraw<TData = void>(id: string, options?: HttpClientResponseOptions): Observable<AngularHttpResponse<TData>>;
-  postSelfServiceRegistrationsIdWithdraw<TData = void>(
-    id: string, options?: HttpClientObserveOptions): Observable<TData | HttpEvent<TData> | AngularHttpResponse<TData>> {
-    if (options?.observe === 'events') {
-      return this.http.post<TData>(
-      `/self-service/registrations/${id}/withdraw`,
-      undefined,{
-        ...(options as Omit<NonNullable<typeof options>, 'observe'>),
-        observe: 'events',
-      }
-    );
-    }
-
-    if (options?.observe === 'response') {
-      return this.http.post<TData>(
-      `/self-service/registrations/${id}/withdraw`,
-      undefined,{
-        ...(options as Omit<NonNullable<typeof options>, 'observe'>),
-        observe: 'response',
-      }
-    );
-    }
-
-    return this.http.post<TData>(
-      `/self-service/registrations/${id}/withdraw`,
-      undefined,{
-        ...(options as Omit<NonNullable<typeof options>, 'observe'>),
-        observe: 'body',
-      }
-    );
-  }
-
 getOpenbaarRegister<TData = OpenbaarEntry[]>(params?: GetOpenbaarRegisterParams, options?: HttpClientBodyOptions): Observable<TData>;
 getOpenbaarRegister<TData = OpenbaarEntry[]>(params?: GetOpenbaarRegisterParams, options?: HttpClientEventOptions): Observable<HttpEvent<TData>>;
 getOpenbaarRegister<TData = OpenbaarEntry[]>(params?: GetOpenbaarRegisterParams, options?: HttpClientResponseOptions): Observable<AngularHttpResponse<TData>>;
--- a/services/bff/Bff.Api/DownstreamClients.cs
+++ b/services/bff/Bff.Api/DownstreamClients.cs
@@ -22,11 +22,6 @@ public interface IDomainClient
 {
    Task<SubmitAccepted> SubmitRegistrationAsync(string bsn, CancellationToken ct = default);

-    /// <summary>Withdraw the caller's own registration ("trek aanvraag in"). Owner-scoped by
-    /// <paramref name="bsn"/>. Returns <c>false</c> when the domain reports the registration is
-    /// unknown or not the caller's (404), so the BFF can relay a 404 rather than a 500.</summary>
-    Task<bool> WithdrawRegistrationAsync(string registrationId, string bsn, CancellationToken ct = default);
-
    /// <summary>The behandelaar's werkbak — registrations awaiting beoordeling.</summary>
    Task<IReadOnlyList<WerkbakItem>> GetWerkbakAsync(CancellationToken ct = default);

@@ -52,17 +47,6 @@ public sealed class DomainClient(HttpClient http) : IDomainClient
        return new SubmitAccepted(dto.RegistrationId, dto.Status);
    }

-    public async Task<bool> WithdrawRegistrationAsync(string registrationId, string bsn, CancellationToken ct = default)
-    {
-        using var response = await http.PostAsJsonAsync(
-            $"registrations/{registrationId}/withdraw", new { bsn }, ct);
-        // The domain 404s an unknown or not-owned registration; relay that rather than fail hard.
-        if (response.StatusCode == System.Net.HttpStatusCode.NotFound)
-            return false;
-        response.EnsureSuccessStatusCode();
-        return true;
-    }
-
    public async Task<IReadOnlyList<WerkbakItem>> GetWerkbakAsync(CancellationToken ct = default)
        => await http.GetFromJsonAsync<List<WerkbakItem>>("behandel/werkbak", ct) ?? [];

--- a/services/bff/Bff.Api/Program.cs
+++ b/services/bff/Bff.Api/Program.cs
@@ -86,24 +86,6 @@ app.MapPost("/self-service/registrations", async (ClaimsPrincipal user, IDomainC
    .Produces(StatusCodes.Status400BadRequest)
    .Produces(StatusCodes.Status401Unauthorized);

-// Self-service withdrawal (S-11): the signed-in zorgprofessional withdraws their own registration.
-// The bsn comes from the DigiD token and is forwarded to the domain, which owner-scopes the action;
-// a registration that is unknown or not the caller's comes back 404 (ownership is not revealed).
-app.MapPost("/self-service/registrations/{id}/withdraw", async (string id, ClaimsPrincipal user, IDomainClient domain, CancellationToken ct) =>
-{
-    var bsn = user.FindFirstValue("bsn");
-    if (string.IsNullOrWhiteSpace(bsn))
-        return Results.BadRequest("The token carries no bsn claim.");
-
-    var withdrawn = await domain.WithdrawRegistrationAsync(id, bsn, ct);
-    return withdrawn ? Results.NoContent() : Results.NotFound();
-})
-    .RequireAuthorization()
-    .Produces(StatusCodes.Status204NoContent)
-    .Produces(StatusCodes.Status400BadRequest)
-    .Produces(StatusCodes.Status401Unauthorized)
-    .Produces(StatusCodes.Status404NotFound);
-
 // Openbaar register: an anonymous public lookup that exposes only public-safe fields (S-09).
 app.MapGet("/openbaar/register", async (string? q, IProjectionClient projection, CancellationToken ct) =>
 {
--- a/services/bff/Bff.Tests/BffFactory.cs
+++ b/services/bff/Bff.Tests/BffFactory.cs
@@ -82,18 +82,6 @@ internal sealed class FakeDomainClient : IDomainClient
        return Task.FromResult(Result);
    }

-    public (string RegistrationId, string Bsn)? Withdrawn { get; private set; }
-
-    /// <summary>Whether the fake domain reports the withdrawal as done (true → 204) or not-found/not-owned
-    /// (false → 404). Tests set this to exercise the relay.</summary>
-    public bool WithdrawSucceeds { get; set; } = true;
-
-    public Task<bool> WithdrawRegistrationAsync(string registrationId, string bsn, CancellationToken ct = default)
-    {
-        Withdrawn = (registrationId, bsn);
-        return Task.FromResult(WithdrawSucceeds);
-    }
-
    public (string RegistrationId, string Besluit)? Decided { get; private set; }

    public Task<IReadOnlyList<WerkbakItem>> GetWerkbakAsync(CancellationToken ct = default)
--- a/services/bff/Bff.Tests/SelfServiceEndpointTests.cs
+++ b/services/bff/Bff.Tests/SelfServiceEndpointTests.cs
@@ -71,46 +71,5 @@ public class SelfServiceEndpointTests
        Assert.Equal("reg-123", body!.RegistrationId);
    }

-    private static HttpRequestMessage Withdraw(string? bearer, string id = "reg-123")
-    {
-        var request = new HttpRequestMessage(HttpMethod.Post, $"/self-service/registrations/{id}/withdraw");
-        if (bearer is not null)
-            request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", bearer);
-        return request;
-    }
-
-    [Fact]
-    public async Task Rejects_a_withdrawal_without_a_token()
-    {
-        using var factory = new BffFactory();
-
-        var response = await factory.CreateClient().SendAsync(Withdraw(bearer: null));
-
-        Assert.Equal(HttpStatusCode.Unauthorized, response.StatusCode);
-        Assert.Null(factory.Domain.Withdrawn);
-    }
-
-    [Fact]
-    public async Task Withdraws_the_callers_registration_forwarding_the_id_and_bsn()
-    {
-        using var factory = new BffFactory();
-
-        var response = await factory.CreateClient().SendAsync(Withdraw(TestTokens.Valid("123456782"), "reg-9"));
-
-        Assert.Equal(HttpStatusCode.NoContent, response.StatusCode);
-        Assert.Equal(("reg-9", "123456782"), factory.Domain.Withdrawn);
-    }
-
-    [Fact]
-    public async Task Relays_not_found_when_the_registration_is_unknown_or_not_the_callers()
-    {
-        using var factory = new BffFactory();
-        factory.Domain.WithdrawSucceeds = false;
-
-        var response = await factory.CreateClient().SendAsync(Withdraw(TestTokens.Valid("123456782")));
-
-        Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
-    }
-
    private sealed record SubmitAcceptedDto(string RegistrationId, string Status);
 }
--- a/services/bff/openapi.json
+++ b/services/bff/openapi.json
@@ -30,37 +30,6 @@
        }
      }
    },
-    "/self-service/registrations/{id}/withdraw": {
-      "post": {
-        "tags": [
-          "Bff.Api"
-        ],
-        "parameters": [
-          {
-            "name": "id",
-            "in": "path",
-            "required": true,
-            "schema": {
-              "type": "string"
-            }
-          }
-        ],
-        "responses": {
-          "204": {
-            "description": "No Content"
-          },
-          "400": {
-            "description": "Bad Request"
-          },
-          "401": {
-            "description": "Unauthorized"
-          },
-          "404": {
-            "description": "Not Found"
-          }
-        }
-      }
-    },
    "/openbaar/register": {
      "get": {
        "tags": [
--- a/services/domain/Big.Api/Program.cs
+++ b/services/domain/Big.Api/Program.cs
@@ -76,19 +76,16 @@ app.MapPost("/registrations/{id}/decide", async (string id, DecideRequest body,
 });

 // Withdraw a registration (S-11): the zorgprofessional pulls their own still-open submission back,
-// advancing it to INGETROKKEN and cancelling its workflow. Owner-scoped by the caller's bsn (the BFF
-// forwards it from the DigiD token, S-11c); a registration that is unknown or not the caller's is
-// 404 (indistinguishable, so ownership isn't leaked). Idempotent.
-app.MapPost("/registrations/{id}/withdraw", async (string id, WithdrawRequest body, WithdrawRegistration withdraw, CancellationToken ct) =>
+// advancing it to INGETROKKEN. Idempotent. The BFF reaches this behind a digid token, owner-scoped
+// to the caller's bsn (S-11c); the domain trusts its callers (§8.3). Cancelling the running Flowable
+// process is a later sub-slice (S-11b).
+app.MapPost("/registrations/{id}/withdraw", async (string id, WithdrawRegistration withdraw, CancellationToken ct) =>
 {
    if (!Guid.TryParse(id, out var guid))
        return Results.NotFound();

-    if (string.IsNullOrWhiteSpace(body?.Bsn))
-        return Results.BadRequest(new { error = "A bsn is required to withdraw a registration." });
-
-    var outcome = await withdraw.HandleAsync(new WithdrawRegistrationCommand(new RegistrationId(guid), body.Bsn), ct);
-    return outcome == WithdrawOutcome.Withdrawn ? Results.NoContent() : Results.NotFound();
+    await withdraw.HandleAsync(new WithdrawRegistrationCommand(new RegistrationId(guid)), ct);
+    return Results.NoContent();
 });

 // The behandelaar's werkbak (S-12): the registrations awaiting beoordeling, read from the open
@@ -116,8 +113,6 @@ public sealed record SubmitRegistrationRequest(string Bsn);

 public sealed record DecideRequest(string Besluit);

-public sealed record WithdrawRequest(string Bsn);
-
 public sealed record RegistrationResponse(string RegistrationId, string Status, string? ZaakUrl);

 public partial class Program;
--- a/services/domain/Big.Application/Ports.cs
+++ b/services/domain/Big.Application/Ports.cs
@@ -15,14 +15,6 @@ public interface IWorkflowClient
    /// aggregate. Returns the process instance id.
    /// </summary>
    Task<string> StartRegistrationProcessAsync(RegistrationId registrationId, CancellationToken ct = default);
-
-    /// <summary>
-    /// Cancel a running <c>registratie</c> process on withdrawal (S-11): correlate the
-    /// <c>RegistratieIngetrokken</c> message to the instance, tripping the interrupting message event
-    /// that ends it (ADR-0014). Best-effort — if the instance is not waiting on that message (already
-    /// ended, or not yet parked) it is a no-op; the aggregate is INGETROKKEN regardless.
-    /// </summary>
-    Task WithdrawProcessAsync(string processInstanceId, CancellationToken ct = default);
 }

 /// <summary>
--- a/services/domain/Big.Application/Werkbak.cs
+++ b/services/domain/Big.Application/Werkbak.cs
@@ -1,5 +1,3 @@
-using Big.Domain;
-
 namespace Big.Application;

 /// <summary>One row of the behandelaar's werkbak: a registration awaiting beoordeling, with the
@@ -10,8 +8,7 @@ public sealed record WerkbakItem(string RegistrationId, string Bsn, string Statu
 /// The werkbak query (S-12c): the registrations awaiting a behandelaar's beoordeling. It reads the
 /// open <c>Beoordelen</c> tasks from the workflow engine (§8.2, via <see cref="IUserTaskClient"/>) —
 /// the authoritative set of work items — and enriches each with its aggregate (bsn + status). A task
-/// whose registration the domain doesn't know, or whose registration is no longer open for beoordeling
-/// (e.g. withdrawn — S-11 — while its task lingers until the workflow cancels it), is skipped.
+/// whose registration the domain doesn't know is skipped rather than invented.
 /// </summary>
 public sealed class Werkbak(IUserTaskClient tasks, IRegistrationStore store)
 {
@@ -23,7 +20,7 @@ public sealed class Werkbak(IUserTaskClient tasks, IRegistrationStore store)
        foreach (var task in open)
        {
            var registration = await store.GetAsync(task.RegistrationId, ct);
-            if (registration is null || !IsOpenForBeoordeling(registration.Status))
+            if (registration is null)
                continue;

            items.Add(new WerkbakItem(
@@ -32,9 +29,4 @@ public sealed class Werkbak(IUserTaskClient tasks, IRegistrationStore store)

        return items;
    }
-
-    // Only registrations still open for a decision belong in the werkbak; a terminal one (decided or
-    // withdrawn — S-11) whose Beoordelen task has not yet been cleared must not surface to a behandelaar.
-    private static bool IsOpenForBeoordeling(RegistrationStatus status)
-        => status is RegistrationStatus.Ingediend or RegistrationStatus.InBehandeling;
 }
--- a/services/domain/Big.Application/WithdrawRegistration.cs
+++ b/services/domain/Big.Application/WithdrawRegistration.cs
@@ -2,54 +2,31 @@ using Big.Domain;

 namespace Big.Application;

-/// <summary>A zorgprofessional's request to withdraw their own registration ("trek aanvraag in").
-/// <paramref name="Bsn"/> is the authenticated caller (from the DigiD token, forwarded by the BFF):
-/// only the registration's own bsn may withdraw it.</summary>
-public sealed record WithdrawRegistrationCommand(RegistrationId RegistrationId, string Bsn);
-
-/// <summary>The outcome of a withdrawal request.</summary>
-public enum WithdrawOutcome
-{
-    /// <summary>The registration is now (or already was) INGETROKKEN.</summary>
-    Withdrawn,
-
-    /// <summary>No registration with that id belongs to the caller — unknown, or owned by someone
-    /// else (the two are deliberately indistinguishable, so the endpoint reveals neither).</summary>
-    NotFound,
-}
+/// <summary>A zorgprofessional's request to withdraw their own registration ("trek aanvraag in").</summary>
+public sealed record WithdrawRegistrationCommand(RegistrationId RegistrationId);

 /// <summary>
 /// The withdrawal use case (S-11): a zorgprofessional pulls a still-open registration back. It
-/// advances the aggregate to INGETROKKEN, persists it, then cancels the running registratie process
-/// by correlating the withdrawal message to its instance (ADR-0014), so the case leaves the
-/// behandelaar's werkbak. Idempotent — a repeated or redelivered withdrawal of an already-withdrawn
-/// registration is a no-op (not persisted or cancelled again). Cancelling is best-effort: if the
-/// registration never started a process the withdrawal still stands (the process cancel is skipped),
-/// mirroring how <see cref="BeoordeelRegistratie"/> completes its task best-effort.
+/// advances the aggregate to INGETROKKEN and persists it. Idempotent — a repeated or redelivered
+/// withdrawal of an already-withdrawn registration is a no-op (the aggregate is not persisted again).
+/// Cancelling the running Flowable process (so the case leaves the behandelaar's werkbak) is a later
+/// sub-slice (S-11b, via a BPMN message event); this sub-slice owns the domain transition only —
+/// mirroring how the beoordeling's rejection deferred its zaak propagation.
 /// </summary>
-public sealed class WithdrawRegistration(IRegistrationStore store, IWorkflowClient workflow)
+public sealed class WithdrawRegistration(IRegistrationStore store)
 {
-    public async Task<WithdrawOutcome> HandleAsync(WithdrawRegistrationCommand command, CancellationToken ct = default)
+    public async Task HandleAsync(WithdrawRegistrationCommand command, CancellationToken ct = default)
    {
        ArgumentNullException.ThrowIfNull(command);

-        var registration = await store.GetAsync(command.RegistrationId, ct);
+        var registration = await store.GetAsync(command.RegistrationId, ct)
+            ?? throw new InvalidOperationException($"No registration {command.RegistrationId} to withdraw.");

-        // Unknown, or not the caller's registration: report NotFound either way (don't reveal which).
-        if (registration is null || registration.Bsn != command.Bsn)
-            return WithdrawOutcome.NotFound;
-
-        // A repeated withdrawal is a no-op: don't persist or cancel the already-withdrawn one again.
+        // A repeated withdrawal is a no-op: don't persist the already-withdrawn aggregate again.
        if (registration.Status == RegistrationStatus.Ingetrokken)
-            return WithdrawOutcome.Withdrawn;
+            return;

        registration.Withdraw();
        await store.SaveAsync(registration, ct);
-
-        // Cancel the running process (if one was started) so its Beoordelen task leaves the werkbak.
-        if (registration.ProcessInstanceId is not null)
-            await workflow.WithdrawProcessAsync(registration.ProcessInstanceId, ct);
-
-        return WithdrawOutcome.Withdrawn;
    }
 }
--- a/services/domain/Big.Infrastructure/FlowableWorkflowClient.cs
+++ b/services/domain/Big.Infrastructure/FlowableWorkflowClient.cs
@@ -23,7 +23,6 @@ public sealed class FlowableWorkflowClient(HttpClient http, FlowableOptions opti
    private const string RegistrationIdVariable = "registrationId";
    private const string ZaakUrlVariable = "zaakUrl";
    private const string BesluitVariable = "besluit";
-    private const string IngetrokkenMessage = "RegistratieIngetrokken";

    public async Task<string> StartRegistrationProcessAsync(RegistrationId registrationId, CancellationToken ct = default)
    {
@@ -86,35 +85,6 @@ public sealed class FlowableWorkflowClient(HttpClient http, FlowableOptions opti
        response.EnsureSuccessStatusCode();
    }

-    public async Task WithdrawProcessAsync(string processInstanceId, CancellationToken ct = default)
-    {
-        // Correlate the withdrawal message to the instance: find the execution subscribed to it (the
-        // interrupting message event's own execution — NOT the user task's), then deliver
-        // messageEventReceived to that execution so the process ends (ADR-0014). If nothing is
-        // subscribed (the process is not parked at Beoordelen) this is a best-effort no-op.
-        var subscribed = await GetAsync<ExecutionQueryResult>(
-            $"service/runtime/executions?messageEventSubscriptionName={IngetrokkenMessage}&processInstanceId={processInstanceId}",
-            ct);
-
-        var execution = subscribed?.Data?.FirstOrDefault();
-        if (execution is null)
-            return;
-
-        var request = new MessageEventRequest("messageEventReceived", IngetrokkenMessage);
-        using var response = await SendAsync(
-            $"service/runtime/executions/{execution.Id}", request, ct, HttpMethod.Put);
-        response.EnsureSuccessStatusCode();
-    }
-
-    private async Task<TResponse?> GetAsync<TResponse>(string path, CancellationToken ct)
-    {
-        var message = new HttpRequestMessage(HttpMethod.Get, new Uri(options.BaseUrl, path));
-        message.Headers.Authorization = new AuthenticationHeaderValue("Basic", BasicCredentials());
-        using var response = await http.SendAsync(message, ct);
-        response.EnsureSuccessStatusCode();
-        return await response.Content.ReadFromJsonAsync<TResponse>(ct);
-    }
-
    private async Task<TResponse?> PostAsync<TRequest, TResponse>(string path, TRequest body, CancellationToken ct)
    {
        using var response = await SendAsync(path, body, ct);
@@ -122,9 +92,9 @@ public sealed class FlowableWorkflowClient(HttpClient http, FlowableOptions opti
        return await response.Content.ReadFromJsonAsync<TResponse>(ct);
    }

-    private Task<HttpResponseMessage> SendAsync<TRequest>(string path, TRequest body, CancellationToken ct, HttpMethod? method = null)
+    private Task<HttpResponseMessage> SendAsync<TRequest>(string path, TRequest body, CancellationToken ct)
    {
-        var message = new HttpRequestMessage(method ?? HttpMethod.Post, new Uri(options.BaseUrl, path))
+        var message = new HttpRequestMessage(HttpMethod.Post, new Uri(options.BaseUrl, path))
        {
            Content = JsonContent.Create(body),
        };
@@ -162,10 +132,6 @@ public sealed class FlowableWorkflowClient(HttpClient http, FlowableOptions opti
        [property: JsonPropertyName("action")] string Action,
        [property: JsonPropertyName("variables")] IReadOnlyList<Variable> Variables);

-    private sealed record MessageEventRequest(
-        [property: JsonPropertyName("action")] string Action,
-        [property: JsonPropertyName("messageName")] string MessageName);
-
    private sealed record TaskQueryResult(
        [property: JsonPropertyName("data")] IReadOnlyList<UserTaskDto>? Data);

@@ -188,11 +154,6 @@ public sealed class FlowableWorkflowClient(HttpClient http, FlowableOptions opti

    private sealed record ProcessInstance([property: JsonPropertyName("id")] string Id);

-    private sealed record ExecutionQueryResult(
-        [property: JsonPropertyName("data")] IReadOnlyList<ExecutionDto>? Data);
-
-    private sealed record ExecutionDto([property: JsonPropertyName("id")] string Id);
-
    private sealed record AcquiredJob(
        [property: JsonPropertyName("id")] string Id,
        [property: JsonPropertyName("variables")] IReadOnlyList<Variable> Variables)
--- a/services/domain/Big.Tests/Fakes.cs
+++ b/services/domain/Big.Tests/Fakes.cs
@@ -32,7 +32,6 @@ internal sealed class FakeWorkflowClient(string processInstanceId = "proc-1", Ac
    : IWorkflowClient
 {
    public RegistrationId? StartedFor { get; private set; }
-    public string? WithdrawnProcessInstanceId { get; private set; }

    public Task<string> StartRegistrationProcessAsync(RegistrationId registrationId, CancellationToken ct = default)
    {
@@ -40,12 +39,6 @@ internal sealed class FakeWorkflowClient(string processInstanceId = "proc-1", Ac
        StartedFor = registrationId;
        return Task.FromResult(processInstanceId);
    }
-
-    public Task WithdrawProcessAsync(string processInstanceId, CancellationToken ct = default)
-    {
-        WithdrawnProcessInstanceId = processInstanceId;
-        return Task.CompletedTask;
-    }
 }

 /// <summary>A fake user-task client for the werkbak/decision use cases: returns a scripted set of
--- a/services/domain/Big.Tests/FlowableWorkflowClientTests.cs
+++ b/services/domain/Big.Tests/FlowableWorkflowClientTests.cs
@@ -242,61 +242,6 @@ public class FlowableWorkflowClientTests
        Assert.Contains($"\"value\":\"{expected}\"", capture.Body);
    }

-    [Fact]
-    public async Task Withdraw_process_correlates_the_message_to_the_subscribed_execution()
-    {
-        HttpRequestMessage? getReq = null;
-        HttpRequestMessage? putReq = null;
-        string? putBody = null;
-        var client = Client(new StubHandler(async req =>
-        {
-            if (req.Method == HttpMethod.Get)
-            {
-                getReq = req;
-                return new HttpResponseMessage(HttpStatusCode.OK)
-                {
-                    Content = new StringContent("""{"data":[{"id":"exec-9"}]}""", Encoding.UTF8, "application/json"),
-                };
-            }
-            putReq = req;
-            putBody = await req.Content!.ReadAsStringAsync();
-            return new HttpResponseMessage(HttpStatusCode.OK);
-        }));
-
-        await client.WithdrawProcessAsync("pi-1");
-
-        // 1. Find the execution subscribed to the withdrawal message for this instance.
-        Assert.Equal(HttpMethod.Get, getReq!.Method);
-        Assert.Contains("service/runtime/executions", getReq.RequestUri!.ToString());
-        Assert.Contains("messageEventSubscriptionName=RegistratieIngetrokken", getReq.RequestUri!.Query);
-        Assert.Contains("processInstanceId=pi-1", getReq.RequestUri!.Query);
-        // 2. Deliver messageEventReceived to that execution (PUT), tripping the interrupting event.
-        Assert.Equal(HttpMethod.Put, putReq!.Method);
-        Assert.Equal("http://flowable/flowable-rest/service/runtime/executions/exec-9",
-            putReq.RequestUri!.ToString());
-        Assert.Contains("\"action\":\"messageEventReceived\"", putBody);
-        Assert.Contains("\"messageName\":\"RegistratieIngetrokken\"", putBody);
-    }
-
-    [Fact]
-    public async Task Withdraw_process_is_a_no_op_when_no_execution_is_subscribed()
-    {
-        var methods = new List<HttpMethod>();
-        var client = Client(new StubHandler(req =>
-        {
-            methods.Add(req.Method);
-            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
-            {
-                Content = new StringContent("""{"data":[]}""", Encoding.UTF8, "application/json"),
-            });
-        }));
-
-        await client.WithdrawProcessAsync("pi-1");
-
-        // No subscribed execution → no message delivered (best-effort), no throw.
-        Assert.DoesNotContain(HttpMethod.Put, methods);
-    }
-
    [Fact]
    public async Task Complete_beoordeling_throws_when_flowable_rejects_the_request()
    {
--- a/services/domain/Big.Tests/WerkbakTests.cs
+++ b/services/domain/Big.Tests/WerkbakTests.cs
@@ -46,19 +46,4 @@ public class WerkbakTests

        Assert.Empty(await werkbak.GetAsync());
    }
-
-    [Fact]
-    public async Task Skips_a_task_whose_registration_is_no_longer_open()
-    {
-        // A withdrawn registration (S-11) may still have a Beoordelen task lingering until the workflow
-        // cancels it; the werkbak lists only registrations still open for beoordeling, so it drops off.
-        var store = new FakeRegistrationStore();
-        var registration = Registration.Submit("123456782");
-        registration.Withdraw();
-        store.Seed(registration);
-        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", registration.Id)]);
-        var werkbak = new Werkbak(tasks, store);
-
-        Assert.Empty(await werkbak.GetAsync());
-    }
 }
--- a/services/domain/Big.Tests/WithdrawRegistrationTests.cs
+++ b/services/domain/Big.Tests/WithdrawRegistrationTests.cs
@@ -5,101 +5,40 @@ namespace Big.Tests;

 public class WithdrawRegistrationTests
 {
-    private const string Bsn = "123456782";
-
-    private static Registration Submitted(string processInstanceId = "proc-1")
-    {
-        var registration = Registration.Submit(Bsn);
-        registration.RecordProcessStarted(processInstanceId);
-        return registration;
-    }
-
-    private static WithdrawRegistrationCommand Command(RegistrationId id, string bsn = Bsn) => new(id, bsn);
-
    [Fact]
    public async Task Withdrawing_marks_the_registration_ingetrokken_and_persists_it()
    {
        var store = new FakeRegistrationStore();
-        var registration = Submitted();
+        var registration = Registration.Submit("123456782");
        store.Seed(registration);
-        var handler = new WithdrawRegistration(store, new FakeWorkflowClient());
+        var handler = new WithdrawRegistration(store);

-        var outcome = await handler.HandleAsync(Command(registration.Id));
+        await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));

-        Assert.Equal(WithdrawOutcome.Withdrawn, outcome);
        var saved = await store.GetAsync(registration.Id);
        Assert.Equal(RegistrationStatus.Ingetrokken, saved!.Status);
        Assert.Equal(1, store.SaveCount);
    }

-    [Fact]
-    public async Task Withdrawing_cancels_the_running_process()
-    {
-        var store = new FakeRegistrationStore();
-        var registration = Submitted("proc-42");
-        store.Seed(registration);
-        var workflow = new FakeWorkflowClient();
-        var handler = new WithdrawRegistration(store, workflow);
-
-        await handler.HandleAsync(Command(registration.Id));
-
-        // The process the registration recorded at submit is cancelled (ADR-0014).
-        Assert.Equal("proc-42", workflow.WithdrawnProcessInstanceId);
-    }
-
-    [Fact]
-    public async Task Withdrawing_before_a_process_was_started_still_marks_ingetrokken()
-    {
-        var store = new FakeRegistrationStore();
-        var registration = Registration.Submit(Bsn); // no RecordProcessStarted
-        store.Seed(registration);
-        var workflow = new FakeWorkflowClient();
-        var handler = new WithdrawRegistration(store, workflow);
-
-        await handler.HandleAsync(Command(registration.Id));
-
-        Assert.Equal(RegistrationStatus.Ingetrokken, (await store.GetAsync(registration.Id))!.Status);
-        Assert.Null(workflow.WithdrawnProcessInstanceId);
-    }
-
-    [Fact]
-    public async Task A_different_bsn_cannot_withdraw_the_registration()
-    {
-        // Owner-scoping: only the zorgprofessional who submitted may withdraw. Another bsn is told
-        // NotFound (we don't reveal the registration exists) and nothing is changed.
-        var store = new FakeRegistrationStore();
-        var registration = Submitted();
-        store.Seed(registration);
-        var workflow = new FakeWorkflowClient();
-        var handler = new WithdrawRegistration(store, workflow);
-
-        var outcome = await handler.HandleAsync(Command(registration.Id, bsn: "999999990"));
-
-        Assert.Equal(WithdrawOutcome.NotFound, outcome);
-        Assert.Equal(RegistrationStatus.Ingediend, (await store.GetAsync(registration.Id))!.Status);
-        Assert.Equal(0, store.SaveCount);
-        Assert.Null(workflow.WithdrawnProcessInstanceId);
-    }
-
    [Fact]
    public async Task Rejects_a_null_command_without_touching_the_store()
    {
        var store = new FakeRegistrationStore();
-        var handler = new WithdrawRegistration(store, new FakeWorkflowClient());
+        var handler = new WithdrawRegistration(store);

        await Assert.ThrowsAsync<ArgumentNullException>(() => handler.HandleAsync(null!));
        Assert.Equal(0, store.SaveCount);
    }

    [Fact]
-    public async Task Withdrawing_an_unknown_registration_is_not_found()
+    public async Task Withdrawing_an_unknown_registration_throws()
    {
        var store = new FakeRegistrationStore();
-        var handler = new WithdrawRegistration(store, new FakeWorkflowClient());
+        var handler = new WithdrawRegistration(store);

-        var outcome = await handler.HandleAsync(Command(RegistrationId.New()));
-
-        Assert.Equal(WithdrawOutcome.NotFound, outcome);
+        var ex = await Assert.ThrowsAsync<InvalidOperationException>(
+            () => handler.HandleAsync(new WithdrawRegistrationCommand(RegistrationId.New())));
+        Assert.Contains("No registration", ex.Message);
        Assert.Equal(0, store.SaveCount);
    }

@@ -107,16 +46,14 @@ public class WithdrawRegistrationTests
    public async Task Re_withdrawing_an_already_ingetrokken_registration_is_idempotent()
    {
        var store = new FakeRegistrationStore();
-        var registration = Submitted();
+        var registration = Registration.Submit("123456782");
        store.Seed(registration);
-        var workflow = new FakeWorkflowClient();
-        var handler = new WithdrawRegistration(store, workflow);
+        var handler = new WithdrawRegistration(store);

-        await handler.HandleAsync(Command(registration.Id));
-        var second = await handler.HandleAsync(Command(registration.Id));
+        await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));
+        await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));

-        // The second withdrawal is a no-op: still Withdrawn, but the aggregate is not persisted again.
-        Assert.Equal(WithdrawOutcome.Withdrawn, second);
+        // The second withdrawal is a no-op: the aggregate is not persisted again.
        Assert.Equal(1, store.SaveCount);
        Assert.Equal(RegistrationStatus.Ingetrokken, (await store.GetAsync(registration.Id))!.Status);
    }
--- a/tests/acceptance/Features/EenRegistratieIntrekken.feature
+++ b/tests/acceptance/Features/EenRegistratieIntrekken.feature
@@ -1,22 +0,0 @@
-# language: en
-# Drives S-11 (#12). A zorgprofessional withdraws their own submitted registration ("trek aanvraag
-# in"): it advances to INGETROKKEN and its running workflow is cancelled (ADR-0014). Only the owner
-# may withdraw — another bsn is told not-found. Exercised against in-memory stand-ins for the store
-# and the Workflow Client; the live Flowable message correlation is verified by the domain check.
-Feature: Een registratie intrekken
-  Als zorgprofessional wil ik mijn ingediende registratie kunnen intrekken
-  zodat een aanvraag die ik niet meer wil niet in behandeling blijft.
-
-  Scenario: De zorgprofessional trekt zijn eigen registratie in
-    Given a submitted registration with a running process
-    When the zorgprofessional withdraws it
-    Then the withdrawal succeeds
-    And the registration has status "INGETROKKEN"
-    And the running process is cancelled
-
-  Scenario: Een andere zorgprofessional kan de registratie niet intrekken
-    Given a submitted registration with a running process
-    When a different zorgprofessional tries to withdraw it
-    Then the withdrawal is reported not found
-    And the registration has status "INGEDIEND"
-    And the running process is not cancelled
--- a/tests/acceptance/Steps/EenRegistratieIntrekkenSteps.cs
+++ b/tests/acceptance/Steps/EenRegistratieIntrekkenSteps.cs
@@ -1,59 +0,0 @@
-using Acceptance.Support;
-using Big.Application;
-using Big.Domain;
-using Reqnroll;
-using Xunit;
-
-namespace Acceptance.Steps;
-
-/// <summary>Bindings for <c>EenRegistratieIntrekken.feature</c> (S-11). Submits a registration (which
-/// records its process) and then applies the WithdrawRegistration use case against in-memory ports;
-/// one instance per scenario. Scoped to this feature so its "the registration has status" step does
-/// not clash with the identically phrased steps in the other features.</summary>
-[Binding]
-[Scope(Feature = "Een registratie intrekken")]
-public sealed class EenRegistratieIntrekkenSteps
-{
-    private const string OwnerBsn = "123456782";
-
-    private readonly InMemoryRegistrationStore _store = new();
-    private readonly InMemoryWorkflowClient _workflow = new();
-    private RegistrationId _id;
-    private WithdrawOutcome _outcome;
-
-    [Given("a submitted registration with a running process")]
-    public async Task GivenASubmittedRegistrationWithARunningProcess()
-        => _id = await new SubmitRegistration(_store, _workflow).HandleAsync(new SubmitRegistrationCommand(OwnerBsn));
-
-    [When("the zorgprofessional withdraws it")]
-    public async Task WhenTheZorgprofessionalWithdrawsIt()
-        => _outcome = await new WithdrawRegistration(_store, _workflow).HandleAsync(
-            new WithdrawRegistrationCommand(_id, OwnerBsn));
-
-    [When("a different zorgprofessional tries to withdraw it")]
-    public async Task WhenADifferentZorgprofessionalTriesToWithdrawIt()
-        => _outcome = await new WithdrawRegistration(_store, _workflow).HandleAsync(
-            new WithdrawRegistrationCommand(_id, "999999990"));
-
-    [Then("the withdrawal succeeds")]
-    public void ThenTheWithdrawalSucceeds() => Assert.Equal(WithdrawOutcome.Withdrawn, _outcome);
-
-    [Then("the withdrawal is reported not found")]
-    public void ThenTheWithdrawalIsReportedNotFound() => Assert.Equal(WithdrawOutcome.NotFound, _outcome);
-
-    [Then("the registration has status \"(.*)\"")]
-    public async Task ThenTheRegistrationHasStatus(string expected)
-    {
-        var registration = await _store.GetAsync(_id);
-        Assert.NotNull(registration);
-        Assert.Equal(expected, registration.Status.ToString().ToUpperInvariant());
-    }
-
-    [Then("the running process is cancelled")]
-    public void ThenTheRunningProcessIsCancelled()
-        => Assert.Equal(InMemoryWorkflowClient.StartedProcessInstanceId, _workflow.WithdrawnProcessInstanceId);
-
-    [Then("the running process is not cancelled")]
-    public void ThenTheRunningProcessIsNotCancelled()
-        => Assert.Null(_workflow.WithdrawnProcessInstanceId);
-}
--- a/tests/acceptance/Support/BffAcceptanceHost.cs
+++ b/tests/acceptance/Support/BffAcceptanceHost.cs
@@ -69,9 +69,6 @@ public sealed class CapturingDomainClient : IDomainClient
        return Task.FromResult(new SubmitAccepted("reg-acc-1", "Ingediend"));
    }

-    public Task<bool> WithdrawRegistrationAsync(string registrationId, string bsn, CancellationToken ct = default)
-        => Task.FromResult(true);
-
    public Task<IReadOnlyList<WerkbakItem>> GetWerkbakAsync(CancellationToken ct = default)
        => Task.FromResult<IReadOnlyList<WerkbakItem>>([]);

--- a/tests/acceptance/Support/InMemoryDomainPorts.cs
+++ b/tests/acceptance/Support/InMemoryDomainPorts.cs
@@ -11,19 +11,12 @@ public sealed class InMemoryWorkflowClient : IWorkflowClient
    public const string StartedProcessInstanceId = "proc-acc-1";

    public RegistrationId? StartedFor { get; private set; }
-    public string? WithdrawnProcessInstanceId { get; private set; }

    public Task<string> StartRegistrationProcessAsync(RegistrationId registrationId, CancellationToken ct = default)
    {
        StartedFor = registrationId;
        return Task.FromResult(StartedProcessInstanceId);
    }
-
-    public Task WithdrawProcessAsync(string processInstanceId, CancellationToken ct = default)
-    {
-        WithdrawnProcessInstanceId = processInstanceId;
-        return Task.CompletedTask;
-    }
 }

 /// <summary>An in-memory ACL stand-in: records the bsn it opened a zaak for and returns a fixed URL,
--- a/tests/e2e/withdrawal.spec.ts
+++ b/tests/e2e/withdrawal.spec.ts
@@ -1,27 +0,0 @@
-import { expect, test } from '@playwright/test';
-
-// S-11 (Flow 3): a zorgprofessional logs in via mock DigiD, submits a registration, then withdraws
-// it ("trek aanvraag in") from the self-service portal. The withdrawal goes portal → BFF (owner-
-// scoped by the DigiD token's bsn) → domain, which cancels the running workflow (ADR-0014); the page
-// then confirms the registration is ingetrokken.
-test('DigiD submit → trek aanvraag in → self-service confirms ingetrokken', async ({ page }) => {
-  // Visiting the guarded page redirects to the Keycloak (mock DigiD) login.
-  await page.goto('/');
-
-  await page.locator('#username').fill('jan-burger');
-  await page.locator('#password').fill('test123');
-  await page.locator('#kc-login').click();
-
-  await expect(page.getByRole('heading', { name: /Zelfservice/i })).toBeVisible();
-
-  await page.getByRole('button', { name: /indienen/i }).click();
-
-  // The BFF accepted it and the page shows the confirmation with the reference.
-  await expect(page.getByText(/ontvangen/i)).toBeVisible();
-
-  // Withdraw it. The confirmation of withdrawal appears only after the decide POST completes (204),
-  // so awaiting the "ingetrokken" text also proves the request landed — no premature navigation.
-  await page.getByRole('button', { name: /trek aanvraag in/i }).click();
-
-  await expect(page.getByText(/is ingetrokken/i)).toBeVisible();
-});
--- a/workflows/registratie.bpmn
+++ b/workflows/registratie.bpmn
@@ -11,13 +11,7 @@
       S-03 added the external task (Workflow Client / ACL). S-12 adds the behandelaar's beoordeling
       as a user task: the process parks here until a behandelaar claims and completes it with a
       `besluit` (goedkeuren/afwijzen). The registrationId set at start rides along as a process
-       variable so the werkbak can correlate each task back to its aggregate.
-       S-11 adds withdrawal: while parked at Beoordelen the citizen can trek de aanvraag in — an
-       interrupting message boundary event (RegistratieIngetrokken) cancels the task and ends the
-       process via a dedicated "ingetrokken" end (ADR-0014). The Workflow Client delivers the message
-       to the task's execution; the BPMN owns the cancellation path. -->
-  <message id="Message_Ingetrokken" name="RegistratieIngetrokken"/>
-
+       variable so the werkbak can correlate each task back to its aggregate. -->
  <process id="registratie" name="Registratie ontvangen" isExecutable="true">

    <startEvent id="start" name="Registratie ontvangen"/>
@@ -35,16 +29,6 @@
    <sequenceFlow id="flow3" sourceRef="Beoordelen" targetRef="end"/>

    <endEvent id="end" name="Registratie beoordeeld"/>
-
-    <!-- Withdrawal (S-11): interrupting message boundary event on Beoordelen. On RegistratieIngetrokken
-         the task is cancelled and the process ends as "ingetrokken". -->
-    <boundaryEvent id="Ingetrokken" attachedToRef="Beoordelen" cancelActivity="true">
-      <messageEventDefinition messageRef="Message_Ingetrokken"/>
-    </boundaryEvent>
-
-    <sequenceFlow id="flow4" sourceRef="Ingetrokken" targetRef="endIngetrokken"/>
-
-    <endEvent id="endIngetrokken" name="Registratie ingetrokken"/>
  </process>

  <bpmndi:BPMNDiagram id="diagram">
@@ -73,16 +57,6 @@
        <omgdi:waypoint x="510" y="115"/>
        <omgdi:waypoint x="580" y="115"/>
      </bpmndi:BPMNEdge>
-      <bpmndi:BPMNShape id="s_ingetrokken" bpmnElement="Ingetrokken">
-        <omgdc:Bounds x="435" y="135" width="30" height="30"/>
-      </bpmndi:BPMNShape>
-      <bpmndi:BPMNShape id="s_endIngetrokken" bpmnElement="endIngetrokken">
-        <omgdc:Bounds x="435" y="220" width="30" height="30"/>
-      </bpmndi:BPMNShape>
-      <bpmndi:BPMNEdge id="e_flow4" bpmnElement="flow4">
-        <omgdi:waypoint x="450" y="165"/>
-        <omgdi:waypoint x="450" y="220"/>
-      </bpmndi:BPMNEdge>
    </bpmndi:BPMNPlane>
  </bpmndi:BPMNDiagram>
 </definitions>