| 1 | # 🤖 Native onboarding: a link → the app → signed in |
| 2 | |
| 3 | **Status: design (2026-07-09), sequenced for building.** The goal, stated as |
| 4 | the experience: someone taps an invite link and ends up **in the native app**, |
| 5 | **in the space**, and **signed in with a passkey** — and when they later set up |
| 6 | their other device (Mac first or iPhone first, either order), the passkey |
| 7 | ceremony on the second device *is* the sync: everything appears. |
| 8 | |
| 9 | This replaces the retired paste-a-link joins (deleted 2026-07-08 with the |
| 10 | sign-in-only door) with something better, not with their return. The design |
| 11 | leans on two invariants from `docs/onboarding-and-home-server.md` that are |
| 12 | already load-bearing: |
| 13 | |
| 14 | - **Deferred claim.** Opening a link never consumes the invite — claiming is |
| 15 | an explicit tap. This is what makes "the app AND the browser both saw the |
| 16 | link" safe: whoever *joins* claims; everyone else just looked. |
| 17 | - **Fragments never reach a server.** The invite secret `T` lives in the |
| 18 | `#fragment`; native parsing (`InviteLink.swift`) and the claim derivation |
| 19 | (`InviteCrypto.derive`) keep it that way. |
| 20 | |
| 21 | ## What already exists (more than it looks) |
| 22 | |
| 23 | The 2026-07-09 create-a-space work built the missing spine without meaning to |
| 24 | advertise it: |
| 25 | |
| 26 | - **`SpaceClaim` (LChatCore)** claims a key-invite **natively**: derive |
| 27 | `{id, wrapKey, claimSecret}` from `T`, `GET /api/key-invite/{id}`, claim for |
| 28 | a device token, generate the identity keypair, register the pubkey, resolve |
| 29 | `myUserId`, even bootstrap the instance key when first-in. Today it handles |
| 30 | the setup-invite shape; the member/DM and add-device shapes are small |
| 31 | extensions (below). |
| 32 | - **Every instance already serves the AASA.** `GET |
| 33 | /.well-known/apple-app-site-association` (main.go `serveAASA`) matches |
| 34 | `/join/*` for the iOS app id on **every** instance, tested in |
| 35 | `handlers_test.go`. The server side of universal links shipped long ago. |
| 36 | - **`inviteLink(fromOpenedURL:)` + `parseJoinLink`** (LChatCore) still parse |
| 37 | both the custom scheme (`elevenmessenger://add?url=…` — the join page's |
| 38 | "Open in Eleven" button) and raw https join links. |
| 39 | - **Passkey sign-in and the vault sync** are shipped on both platforms; the |
| 40 | cross-device story ("the second device's passkey dance does the sync") is |
| 41 | already true for everything in the vault. |
| 42 | |
| 43 | What's missing is the *middle*: neither app currently handles a join URL at |
| 44 | all (iOS has no `onOpenURL`; the Mac accepts only the sign-in callback), the |
| 45 | iOS `applinks` entitlement covers `*.elevenmessenger.com` but not `*.11ch.at` |
| 46 | where the fleet actually lives, and there's no native welcome screen. |
| 47 | |
| 48 | ## The flow, end to end |
| 49 | |
| 50 | ### A. The link opens the app (iOS first) |
| 51 | |
| 52 | 1. **Entitlements**: add `applinks:*.11ch.at` beside the existing |
| 53 | `applinks:*.elevenmessenger.com`. (Apple's rule: one wildcard prefix per |
| 54 | entry, every domain named in the shipped binary — so arbitrary custom |
| 55 | domains like `chat.paulca.com` can't be covered generically. They keep the |
| 56 | web join page, which still works everywhere, plus its "Open in Eleven" |
| 57 | custom-scheme button that reaches the same handler.) |
| 58 | 2. **Handlers**: `onOpenURL` + `onContinueUserActivity(NSUserActivityTypeBrowsingWeb)` |
| 59 | on the iOS root → `inviteLink(fromOpenedURL:)` → `parseJoinLink` → present |
| 60 | the **welcome card** (never claim here — deferred claim). |
| 61 | 3. App not installed: the link lands on the web join page exactly as today. |
| 62 | Distribution polish (smart App Store banner on join.html) is phase 4 of |
| 63 | the onboarding doc and stays there. |
| 64 | |
| 65 | ### B. The native welcome card |
| 66 | |
| 67 | A sheet with the space's **public branding** (`/api/group` name + |
| 68 | `/api/server-avatar` — public by design so this exact card can exist), the |
| 69 | suggested name from the fragment's `~name` tail prefilled into a name field, |
| 70 | and one button: **Join**. Tapping Join is the explicit claim. |
| 71 | |
| 72 | `SpaceClaim` grows the two remaining invite shapes (both already documented in |
| 73 | join.js): |
| 74 | |
| 75 | - **Member/DM invite** (`{threadKey}` payload): decrypt the thread key with |
| 76 | `wrapKey`, generate the keypair, wrap the thread key to our own new pubkey, |
| 77 | send that as `wrapped` in the claim. Lands in the pending DM. |
| 78 | - **Add-device link** (`{priv, pub}` payload): adopt the existing identity — |
| 79 | no new keypair, no label publish. |
| 80 | |
| 81 | Either way the result is a `SavedInstance` through the same `app.add` path, |
| 82 | which persists it, selects it, and pushes it to the vault when signed in. |
| 83 | |
| 84 | ### C. The passkey moment |
| 85 | |
| 86 | Right after landing in the space — not before, the chat is the payoff — the |
| 87 | app makes the save-your-spaces ask: |
| 88 | |
| 89 | - **No home session yet**: one inline card at the top of the thread list |
| 90 | (never a toast): "Keep this space safe — save it to Eleven" → the existing |
| 91 | explicit mint (`HomeSignInModel.backUp`). This is the native twin of the |
| 92 | welcome conversation's `access` step, which deliberately runs *first* on |
| 93 | the web too. Declining defers, matching the web's reminder cadence. |
| 94 | - **Session exists** (e.g. an invited member who already had Eleven): nothing |
| 95 | to ask — `app.add` already pushed the new space into the vault. |
| 96 | |
| 97 | ### D. The second device |
| 98 | |
| 99 | Nothing new to build: install the app → **Sign in** → the passkey ceremony |
| 100 | restores the vault → every space appears with credentials, order, stars. This |
| 101 | is shipped behavior; the design just makes it the *stated* contract: **the |
| 102 | sync IS the sign-in.** |
| 103 | |
| 104 | ### E. The Mac |
| 105 | |
| 106 | Same shape, one platform beat behind (iOS-first rule): |
| 107 | |
| 108 | 1. Server: `serveAASA` adds the Mac app id |
| 109 | (`J5NDF5PCD8.com.elevenmessenger.messenger.mac`) beside the iOS one — |
| 110 | **done** (PR #1383). |
| 111 | 2. Entitlements: the Mac gains its first `applinks` entries (same domains) — |
| 112 | **done** (`LChatMac.entitlements`, with #1383's server half; the Mac App |
| 113 | ID needs the Associated Domains capability before a release build's |
| 114 | profile authorizes it). |
| 115 | 3. `LChatMacApp.onOpenURL` grows a second accepted URL family: join links → |
| 116 | the same welcome card in a sheet. |
| 117 | |
| 118 | macOS routes universal links less aggressively than iOS (browser-first unless |
| 119 | the user opts in), so the join page's "Open in Eleven" button matters more |
| 120 | here — it fires the custom scheme, which macOS routes unconditionally. |
| 121 | |
| 122 | ## What deliberately stays out |
| 123 | |
| 124 | - ~~**No welcome *conversation* natively (yet).**~~ **Superseded — the |
| 125 | interpreter shipped.** The Swift flow interpreter is real now |
| 126 | (`FlowEngine.swift` running the bundled `Flows/welcome.json`, a byte-derived |
| 127 | copy of `welcome.flow.js` drift-gated by `test/flow.test.mjs`, hosted by |
| 128 | `ElevenConversationModel`), and a native member/DM-invite claim creates the |
| 129 | welcome app-thread and lands the joiner in the full conversation — which |
| 130 | asks their name — on both platforms (`SpaceClaim.claim` → |
| 131 | `WelcomeLanding.markPending`/`threadToLand`, #1376). The passkey ceremony |
| 132 | step stays web-only by design (`env.native` skips it — native access *is* |
| 133 | the sign-in). |
| 134 | - **No QR scanning revival, no paste field.** Links open the app; that's the |
| 135 | door. (The `NSCameraUsageDescription` string left from the retired QR flow |
| 136 | should be dropped when the welcome card lands.) |
| 137 | - **No change to web joins.** join.html remains the universal fallback and |
| 138 | the only path on uncovered custom domains. |
| 139 | |
| 140 | ## Build order |
| 141 | |
| 142 | 1. **iOS**: entitlement + URL handlers + welcome card + `SpaceClaim` member/DM |
| 143 | + add-device shapes (with tests against join.js's shapes) + the |
| 144 | post-join passkey nudge. Ships alone; Mac unaffected. |
| 145 | 2. **Server**: AASA gains the Mac app id (one-line change + test update). |
| 146 | 3. **Mac**: entitlements + handler + the same card. |
| 147 | 4. **Polish**: smart banner on join.html; drop the stale camera-permission |
| 148 | string; revisit the welcome conversation once scripts run natively. |
| 149 | |
| 150 | ## Risks / open questions |
| 151 | |
| 152 | - **TestFlight + associated domains**: applinks work on TestFlight builds via |
| 153 | the AASA's app id — no `?mode=developer` needed for the new wildcard (that |
| 154 | mode never worked on macOS anyway; see LChatMac-Dev.entitlements). |
| 155 | - **Wildcard AASA fetch**: Apple's CDN fetches the AASA per-host on install; |
| 156 | `*.11ch.at` hosts each serve it (single binary — already true). |
| 157 | - **A claimed-but-never-saved device**: someone joins natively, never saves a |
| 158 | passkey, loses the phone → the space is orphaned like any keyless loss. |
| 159 | Unchanged from web behavior; the reminder cadence is the mitigation. |
| 160 | |
amadan