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# Didit digital ID wallets — integrate in 5 minutes

You are adding digital ID wallet sign-in to my_stack. The user signs in with a
government or bank digital identity and the wallet returns signed attributes.
Every URL, header, and enum value below is canonical — do not paraphrase or
"improve" them.

## 1. Provision an account
- Sign up: https://business.didit.me (no credit card required).
- Grab the API key for your application from the console.

## 2. Read the methods catalog first
Wallet availability is server-driven per country. Never hard-code a wallet list.

Read the catalog one of these ways:
  - Business Console: your application -> Workflows -> the ID Verification
    step -> Countries -> "Wallets accepted". Coming-soon wallets are listed
    but cannot be switched on. https://docs.didit.me/console/id-verification-methods
  - Didit MCP server (https://mcp.didit.me/mcp), tool
    didit_workflow_get_id_verification_methods_catalog; pass country as ISO
    3166-1 alpha-3 to narrow it. The MCP server signs in with "Log in with
    Didit" (OAuth). It does not accept the x-api-key.
    https://docs.didit.me/integration/mcp/tools
  - Public coverage table (no sign-in, read-only):
    https://docs.didit.me/core-technology/id-verification/digital-id-wallets#supported-wallets
If your code holds only an API key, it cannot read the catalog itself: use the
wallet ids listed in this prompt, and treat the answer of the workflow save as
the check. A live application answers 400 for a wallet that is not available
in that country ("<wallet> is not offered in <ISO3>", "unknown wallet").

The catalog gives you, per wallet id: the display name, the countries it
covers, the issuing authority, the level of assurance, the availability state,
and the attributes it returns. When this prompt was generated it marked these
available:
  - MitID: wallet id mitid, country keys DNK
  - BankID: wallet id bankid_se, country keys SWE
  - Finnish Trust Network: wallet id ftn, country keys FIN
  - Smart-ID: wallet id smart_id, country keys EST, LVA, LTU, BEL
  - Mobile-ID: wallet id mobile_id, country keys EST, LTU
Finnish Trust Network has its own integration guide:
https://docs.didit.me/core-technology/id-verification/finnish-trust-network
iDIN and other wallets remain coming soon until the catalog in
your environment marks them available. Check it; do not hard-code a date.

## 3. Create a workflow with the ID Verification (OCR) feature
POST https://verification.didit.me/v3/workflows/
  -H "x-api-key: <your-api-key>"
  -H "Content-Type: application/json"

The ID Verification feature's enum value is OCR (UPPERCASE — strict enum;
there is no ID_VERIFICATION alias and the API rejects it). Wallets are its
wallet method, accepted per country under config.methods on that same
feature entry, in the same request. Keys are ISO 3166-1 alpha-3.

{
  "workflow_label": "Wallet onboarding",
  "features": [
    {
      "feature": "OCR",
      "config": {
        "methods": {
          "DNK": {
            "document": { "enabled": true },
            "wallet": {
              "enabled": true,
              "providers": ["mitid"],
              "on_failure": "fallback_to_document"
            }
          },
          "FIN": {
            "document": { "enabled": true },
            "wallet": {
              "enabled": true,
              "providers": ["ftn"],
              "on_failure": "fallback_to_document"
            }
          }
        }
      }
    }
  ]
}

Response: 201. The workflow id is uuid (workflow_id carries the same value);
the workflow is published straight away. Create it once and keep the id:
every call to this endpoint makes a new workflow.
is_desktop_allowed defaults to false: on a desktop browser the hosted flow
then shows a QR code to continue on a phone. Add "is_desktop_allowed": true
next to workflow_label to let people finish on desktop.
Use that id as workflow_id in step 4. The ID Verification node id of a
workflow made by this call is "ocr".

Rules that the API enforces:
  - providers is an accept-list, not a ranking. Order carries no meaning and
    the end user picks
  - on_failure is either fallback_to_document or decline. It covers all three
    cases: no wallet, cancelled, sign-in failed
  - a wallet id the catalog does not mark available for that country is
    rejected, and the rejection fails the whole save — including any lookup
    configuration next to it. For unavailable wallets, keep wallet.enabled
    false (or omit the wallet block) so the save succeeds. A sandbox
    application accepts coming-soon wallets, so this only shows on live
  - unknown wallet ids already saved on a workflow are preserved untouched, so
    a config written by a newer console version is never silently dropped
  - a country with no method enabled is rejected at publish time

## 4. Create a session
POST https://verification.didit.me/v3/session/
  -H "x-api-key: <your-api-key>"
  -H "Content-Type: application/json"
  -d '{ "workflow_id": "<id from step 3>", "vendor_data": "<your user id>" }'

Response: 201 with session_id, session_token, url and status "Not Started".
Redirect the user to url (hosted flow) or open it in the Web, iOS, Android,
React Native or Flutter SDK. The field is named url on this response.
One unfinished session exists per workflow_id and vendor_data pair: calling
create again with the same pair answers 201 again with that same session.
Didit shows the accepted wallets for the user's country with their brand marks,
hands off to the wallet, and waits for the signed assertion to come back.

## 5. Webhooks
Register a destination in the console (API & Webhooks), or over the API:

POST https://verification.didit.me/v3/webhook/destinations/
  -H "x-api-key: <your-api-key>"
  -H "Content-Type: application/json"
  -d '{
    "label": "Verification webhooks",
    "url": "https://<your-public-host>/webhooks/didit",
    "webhook_version": "v3",
    "subscribed_events": ["status.updated", "data.updated"]
  }'

label, url and subscribed_events are required. url must be a public HTTPS
address: Didit does not deliver to localhost or private addresses. Response:
201 with uuid and secret_shared_key. Store secret_shared_key as the webhook
secret (DIDIT_WEBHOOK_SECRET); it is unique to this destination. Remove a
destination with DELETE /v3/webhook/destinations/{uuid}/ (204).

What arrives:
  - webhook_type is "status.updated" (the session changed status) or
    "data.updated" (verification data was corrected after the fact)
  - a destination receives the events of every session of the application,
    so filter on workflow_id or vendor_data when several flows share it
  - creating a session already sends status.updated with status
    "Not Started". The decision key is present only when status is Approved,
    Declined, In Review or Abandoned.

Verify every delivery:

  Header:      X-Signature-V2   (NOT X-Signature, NOT X-Signature-Simple)
  Algorithm:   HMAC-SHA256, hex digest, over the CANONICAL JSON of the payload
               — the sender's Python json.dumps(sort_keys=True,
               separators=(",", ":"), ensure_ascii=False) after whole-valued
               floats become ints. Reproduce those bytes EXACTLY; do NOT
               "parse, sort keys, JSON.stringify", which fails in four ways:
               numbers come from the wire TEXT, never from parsed doubles
               (read the body with express.text, not express.json(),
               registered ABOVE any global app.use(express.json()), and
               re-emit integers through BigInt(source) — JSON.parse rounds
               1000000000000000129); floats use Python's repr (1e-05, not
               0.00001; 27.0 becomes 27); keys sort by Unicode CODE POINT as
               strings ("10" before "2", U+FF21 before U+1F642, which
               JavaScript's default .sort() reverses); and the bytes come
               straight from the sorted entries, never from a rebuilt object.
               Do NOT hash the raw request bytes — that is the v1
               X-Signature algorithm and fails for V2 whenever whitespace or
               key order differs from the canonical form.
  Freshness:   the signed body field timestamp is the dispatch time (Unix
               seconds, refreshed on every retry). Reject when
               abs(now - timestamp) > 300 seconds, and reject when the
               X-Timestamp header does not equal it. The header is not
               covered by the signature, so it must never be the only replay
               check: a captured delivery replays with just that header
               refreshed.
  Idempotency: event_id is the same on every retry of one event, so store it
               and skip a delivery you already processed. One session can
               still send the same status under two event ids, and the
               console's Try Webhook test deliveries carry no event_id, so
               also make the handler safe to run twice for one
               (session_id, status, webhook_type).
  Compare:     constant-time (crypto.timingSafeEqual)

Reference handler (Express). Keep the verification lines as written.
The handler is a fragment. Put this above it and app.listen(process.env.PORT)
below it. It needs Express and Node 21 or newer (an older Node rejects
every delivery). It expects a JSON body: answer 400 yourself if you accept
anything else on this route, and refuse to start without the secret.

const express = require("express");
const app = express();
const SECRET = process.env.DIDIT_WEBHOOK_SECRET; // secret_shared_key of the destination

// Your endpoint receives a signed payload
const crypto = require("node:crypto"); // ESM: import crypto from "node:crypto"
// X-Signature-V2 = HMAC over the canonical JSON, never the raw bytes. Match the sender byte for
// byte: keys sorted by code point, integers digit for digit, floats in Python's repr.
class Num { constructor(src) { this.src = src; } } // a number as written on the wire, not a double
const num = (s) => { if (/^-?\d+$/.test(s)) return BigInt(s).toString(); const n = +s; // ints stay exact
  if (Number.isInteger(n)) return BigInt(n).toString(); const [m, e] = n.toExponential().split("e"); // 27.0 -> 27
  return +e >= -4 ? String(n) : `${m}e-${String(-e).padStart(2, "0")}`; }; // 1e-05, not 0.00001
const byCodePoint = (a, b) => Buffer.compare(Buffer.from(a), Buffer.from(b)); // UTF-8 order = Python's
const canon = (v) => Array.isArray(v) ? `[${v.map(canon)}]` : v instanceof Num ? num(v.src)
  : v && typeof v === "object" ? `{${Object.keys(v).sort(byCodePoint).map((k) => `${JSON.stringify(k)}:${canon(v[k])}`)}}`
  : JSON.stringify(v);
// Read the body as text: express.json() would round 1000000000000000129 to a double first.
// Register this route ABOVE any global app.use(express.json()): the first parser to run
// consumes the stream, and a body it already parsed has lost the digits the signature covers.
app.post("/webhooks/didit", express.text({ type: "application/json" }), (req, res) => {
  const exact = JSON.parse(req.body, (k, v, c) => typeof v === "number" ? new Num(c.source) : v); // Node 21+
  const body = JSON.parse(req.body);
  const mac = crypto.createHmac("sha256", SECRET).update(canon(exact), "utf8").digest("hex");
  const sig = Buffer.from(String(req.headers["x-signature-v2"] ?? ""));
  // Freshness comes from the signed body timestamp; the header alone is unsigned and replayable.
  const ts = body.timestamp, fresh = String(ts) === req.headers["x-timestamp"]
    && Math.abs(Date.now() / 1000 - ts) <= 300;
  if (!fresh || sig.length !== mac.length
    || !crypto.timingSafeEqual(sig, Buffer.from(mac))) return res.sendStatus(401);
  const { status, decision } = body;
  // One entry per ID Verification node; pick yours by node_id when you run several.
  const [idv] = decision?.id_verifications ?? [];
  // idv.verification_method: "document" | "id_lookup" | "wallet"
  res.sendStatus(200);
});

Body fields you will use: event_id, session_id, status, webhook_type,
workflow_id, vendor_data, timestamp, decision.
Status values (exact strings): Not Started, In Progress, Approved, Declined,
In Review, Resubmitted, Expired, Abandoned, Kyc Expired. Awaiting User only
appears on business verification sessions.

## 6. Reading the result
The same V3 decision reaches you two ways:
  - webhook body: body.decision.id_verifications[]
  - GET https://verification.didit.me/v3/session/{session_id}/decision/
      -H "x-api-key: <your-api-key>"
    This response IS the decision object. Read id_verifications at the top
    level: there is no decision wrapper here.
Until the user finishes the ID step, status is "Not Started" or "In Progress"
and id_verifications is null, not an empty array. Guard for it.

The decision is the V3 shape: every feature result is a plural array with one
entry per workflow node. ID Verification results live in
id_verifications[]: there is no singular kyc (that is the V2 shape) and no
id_verification. The decision's features list names the step
ID_VERIFICATION, while the workflow body takes OCR. Select your entry by node_id (the
id of your ID Verification node in the workflow graph); with a single ID step,
take index 0. Each entry carries, next to the document fields:

  verification_method    "document" | "id_lookup" | "wallet"
  assurance              "documentary" | "data_match" | "cryptographic"
  wallet_provider        the catalog wallet id the user signed in with; null
                         on document and id_lookup entries
  wallet_verification    provider, provider_name, issuing_authority,
                         issuing_country, credential_type, level_of_assurance
                         (low | substantial | high), verified_at,
                         signature_valid, attributes (what the wallet shared),
                         portrait when the wallet shares one; null otherwise
  fallback_from          { method, reason, action } when the wallet sign-in failed
                         and on_failure declined the session; otherwise
                         null. After a document fallback that succeeds the
                         entry reads verification_method "document" with
                         fallback_from null

A wallet entry that succeeds is assurance cryptographic: an identity provider
authenticated the person and signed the attributes. The normalised full_name
and date_of_birth sit on the entry itself; attributes holds the wallet's own
claims. On a live application, check wallet_verification.signature_valid
before you trust attributes.
Field-by-field reference: https://docs.didit.me/reference/data-models#id-verification

## 7. Billing
  - published customer prices in USD per completed wallet verification:
    - MitID personal: $0.25; production availability: Available
    - BankID Sweden: $0.20; production availability: Available
    - Finnish Trust Network: $0.25; production availability: Available
    - Smart-ID: $0.20; production availability: Available
    - Mobile-ID: $0.20; production availability: Available
    - BankID Norway High: $0.35; production availability: Coming soon
    - Vipps Plus: $0.25; production availability: Coming soon
    - Buypass ID: Coming soon; production availability: Coming soon
    - itsme: Coming soon; production availability: Coming soon
    - iDIN full identification: $0.85; production availability: Coming soon
    - Personalausweis Profile 2: $0.45; production availability: Coming soon
    - Freja eID: $0.25; production availability: Coming soon
    - UAE PASS: Coming soon; production availability: Coming soon
    - gov.br: Coming soon; production availability: Coming soon
    - OneID: $2.50; production availability: Coming soon
    - GOV.UK Wallet: Coming soon; production availability: Coming soon
    - Bank iD: Coming soon; production availability: Coming soon
    - MojeID: Coming soon; production availability: Coming soon
    - Diia: Coming soon; production availability: Coming soon
    - FranceConnect: Coming soon; production availability: Coming soon
    - Auðkenni: Coming soon; production availability: Coming soon
    - ConnectID: Coming soon; production availability: Coming soon
    - EUDI Wallet: Coming soon; production availability: Coming soon
    - Estonian ID-card: $0.55; production availability: Coming soon
    - eParaksts mobile: $0.55; production availability: Coming soon
  - an announced price does not enable a wallet; check the live workflow catalog
  - wallet checks are outside the document free tier; other checks are billed separately
  - full pricing: https://docs.didit.me/core-technology/id-verification/digital-id-wallets#pricing
  - document capture bills its own price when the user falls back

## 8. Hard rules — do not change
  - base URL for v3 endpoints: verification.didit.me
  - auth header: x-api-key (lowercase, hyphenated)
  - webhook headers: X-Signature-V2 plus X-Timestamp; canonical JSON, never
    raw bytes; freshness from the signed body timestamp
  - feature enum: OCR (uppercase) — the ID Verification feature; per-country
    methods go under its config.methods
  - method keys: document, id_lookup, wallet (lowercase, snake_case)
  - wallet ids come from the catalog verbatim, lowercase, snake_case
  - country keys: ISO 3166-1 alpha-3, uppercase
  - result path: decision.id_verifications[] in the webhook body and
    id_verifications[] on the GET decision response, never kyc

## 9. Verify your integration
Sandbox (an application in sandbox mode: nothing is billed and no real eID is
called). https://docs.didit.me/integration/sandbox-testing
  - a sandbox application can enable every wallet in the catalog, the
    coming-soon ones included. A workflow that saves in sandbox can still be
    refused on a live application, so only use wallets marked available.
  - open the session url, pick the wallet and confirm: the default approve
    scenario simulates the sign-in. The entry then has verification_method
    "wallet", assurance "cryptographic" and wallet_provider set, and the
    normalised full_name and date_of_birth are filled. But
    wallet_verification.signature_valid and level_of_assurance are null and
    attributes is { "sandbox": true }: no real credential was checked.
    Assert signature_valid === true and the level of assurance only against
    a live application.
  - to exercise on_failure, create the session with
    "sandbox_scenario": "wallet_cancelled" (also wallet_timeout and
    wallet_provider_error). The wallet sign-in then fails and the flow moves
    to document capture or declines, as on_failure says. A fallback that
    ends in an approved document reads verification_method "document".
  - POST /v3/session/{session_id}/simulate/ forces a final status but writes
    no id_verifications entry, so it cannot stand in for a sign-in.

Checks:
  - create the workflow, create a session, and read its decision: expect 201,
    201 with url, and 200 with status "Not Started"
  - run one session per accepted wallet in sandbox through the hosted flow
  - assert the id_verifications[] entry for your node has verification_method
    wallet and wallet_provider set to the wallet you picked
  - run one session with sandbox_scenario "wallet_cancelled" and assert your
    on_failure setting actually fires
  - on a live application, assert wallet_verification.signature_valid is true
  - assert your webhook accepts a correctly signed payload with reordered
    keys, whitespace and integer-like metadata keys ("10" before "2"), and
    rejects a wrong X-Signature-V2, a payload whose signed timestamp is older
    than 300 seconds, and that same stale payload with only the X-Timestamp
    header refreshed

Docs: https://docs.didit.me/integration/integration-prompt