You are a constitutional council ranking individual git commits for ownership allocation.

Compare these two commits. Decide which contributed more lasting value to the project.

Judge substance, not spectacle:
- Prefer correct, lasting design and real bugfixes over churn, formatting, renames, or generated noise.
- Prefer clarity and necessity over sheer line count. A small precise change can beat a large diffuse one.
- Do not favor a side merely because its patch is longer or noisier.
- Weight what the change does for the project, not the contributor's name.

Return ONLY a JSON object: {"winner": "A" or "B", "ratio": "N:M", "explanation": "..."}
The explanation must cite concrete differences in the patches (1-3 sentences).

Side A — contributor: tommy-mor
Side A — commit message:
[880eb778] Harden auth: fail-closed votes, mock OAuth gate, Secure cookies.

Also show the current alias in the top nav and pin durable by rev.

Co-authored-by: Cursor <cursoragent@cursor.com>

Side A — unified diff (full patch):
diff --git a/AGENTS.md b/AGENTS.md
index babb889d6fbfb1fa7176c9e6b7544ae17b61dd2e..6e0fd8ebb65d665c9c1438e3275971d62b98fd95 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -10,11 +10,11 @@ Single Rust web app **`sorter2-server`**: pairwise voting, rank-centrality ranki
 
 - **Bootstrap script**: `./scripts/cursor-env-install.sh` (also run via `.cursor/environment.json` on Cloud Agent boot) installs Playwright Chromium, Babashka, bbin, `clj-paren-repair`, and warms the RocksDB build.
 - **Rust 1.88+** is required (`rust-toolchain.toml`). The Cloud Dockerfile and `cursor-env-install.sh` install **rustup** 1.88.0 first so `cargo` works while Playwright/Clojure bootstrap continues. Do not rely on `/usr/local/cargo` (often missing or stale).
-- **RocksDB / `durable`**: Ubuntu’s default `c++` is often **clang** without libc++ headers. Set **`CXX=g++`** and **`RUSTFLAGS="-C linker=g++"`** (or `CC=gcc`) before `cargo build` / `cargo test` — both are set in the bootstrap script and `.cursor/environment.json`.
+- **RocksDB / `durable`**: `durable` is an external git dependency (`tommy-mor/durable`, pinned by rev in `server/Cargo.toml`). Ubuntu’s default `c++` is often **clang** without libc++ headers. Set **`CXX=g++`** and **`RUSTFLAGS="-C linker=g++"`** (or `CC=gcc`) before `cargo build` / `cargo test` — both are set in the bootstrap script and `.cursor/environment.json`.
 - **System packages** for builds: `build-essential`, `g++`, `clang`, `libclang-dev`, `pkg-config`, `libssl-dev`, `openjdk-21-jre-headless` (for `reqwest` / OpenSSL, `librocksdb-sys`, `zstd-sys` / bindgen, and **bbin** / Clojure JVM). The bootstrap sets **`JAVA_HOME`** when Java is present.
 - **Clojure CLI 1.12.0.1530** (used in CI): install from https://clojure.org/guides/install_clojure — needed for `./scripts/clj-test.sh` / Kaocha tests.
 - **Babashka / bbin / clj-paren-repair**: installed by `cursor-env-install.sh` into `~/.local/bin` (bb tasks in `bb.edn`, delimiter repair for Clojure edits).
-- **Playwright** (Spel browser tests in `test/vote_compare.clj`): Chromium via `clojure -M -e "(com.microsoft.playwright.CLI/main ...)"` — run once after clone or use the bootstrap script.
+- **Playwright** (Spel browser tests in `test/vote_compare.clj` / `test/auth_login.clj`): Chromium via `clojure -M -e "(com.microsoft.playwright.CLI/main ...)"` — run once after clone or use the bootstrap script.
 
 ### Commands (see also `TEST.sh`)
 
@@ -34,13 +34,17 @@ Environment variables (defaults in `server/src/state.rs`):
 - `PORT` — default `8080`
 - `SORTER2_DATA_DIR` — default `./data` (created on startup)
 - `SORTER2_EVENT_LOG` — default `{data_dir}/events.jsonl`
+- `SORTER2_BASE_URL` — public origin (also drives Secure cookies when `https://`)
+- `GITHUB_CLIENT_ID` / `GITHUB_CLIENT_SECRET` — GitHub OAuth (optional; login disabled if unset)
+- `SORTER2_ALLOW_MOCK_OAUTH=1` — allow `mock_user` on `/auth/github` (tests only)
 
 Health check: `GET /healthz` → `ok`.
 
-Core UI flow: `POST /ui` with form field `__rpc__` (JSON). Example vote:
+Core UI flow: `POST /ui` with form field `__rpc__` (JSON). Votes require a session cookie (sign in via `/login`). Example vote:
 
 ```bash
 curl -sf -X POST http://127.0.0.1:8080/ui \
+  --cookie "sorter2_session=..." \
   --data-urlencode '__rpc__={"action":"record_vote","a":"alpha","b":"beta","ratio_left":2,"ratio_right":1}'
 ```
 
diff --git a/Cargo.lock b/Cargo.lock
index aa02997ad85777195f135bfd9456bcee0fc9a590..1f8690f3e486d099577a32c2ece48caf57ea7160 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -414,7 +414,7 @@ dependencies = [
 [[package]]
 name = "durable"
 version = "0.2.0"
-source = "git+https://github.com/tommy-mor/durable.git?branch=main#a6c14eaa809693140eea0c22b07ef24d8e74adaf"
+source = "git+https://github.com/tommy-mor/durable.git?rev=a6c14eaa809693140eea0c22b07ef24d8e74adaf#a6c14eaa809693140eea0c22b07ef24d8e74adaf"
 dependencies = [
  "ciborium",
  "durable-derive",
@@ -426,7 +426,7 @@ dependencies = [
 [[package]]
 name = "durable-derive"
 version = "0.2.0"
-source = "git+https://github.com/tommy-mor/durable.git?branch=main#a6c14eaa809693140eea0c22b07ef24d8e74adaf"
+source = "git+https://github.com/tommy-mor/durable.git?rev=a6c14eaa809693140eea0c22b07ef24d8e74adaf#a6c14eaa809693140eea0c22b07ef24d8e74adaf"
 dependencies = [
  "proc-macro2",
  "quote",
diff --git a/server/Cargo.toml b/server/Cargo.toml
index dfa39beddecfa37dcdeaa602cb30f4b547528fbb..bd88687fb0ba47d68f2c08eb5e11d0e08b7c4398 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -25,7 +25,7 @@ futures-util = { version = "0.3", default-features = false, features = ["std"] }
 rand = "0.8"
 urlencoding = "2"
 url = "2"
-durable = { git = "https://github.com/tommy-mor/durable.git", branch = "main" }
+durable = { git = "https://github.com/tommy-mor/durable.git", rev = "a6c14eaa809693140eea0c22b07ef24d8e74adaf" }
 
 [dev-dependencies]
 reqwest = { version = "0.12", features = ["json"] }
diff --git a/server/src/api/ui_html.rs b/server/src/api/ui_html.rs
index b86581b1f337650564274254d840e8a75b49524d..9da62ffbed07eb28729aa3160bf33b07ce0d7945 100644
--- a/server/src/api/ui_html.rs
+++ b/server/src/api/ui_html.rs
@@ -71,10 +71,16 @@ pub async fn post_ui_html(
                 return resp;
             }
             let parent = parent_from_scope(&scope);
-            let actor = resolve_vote_actor(
+            let actor = match resolve_vote_actor(
                 state.projection_store.db(),
                 session_id_from_jar(&jar).as_deref(),
-            );
+            ) {
+                Ok(actor) => actor,
+                Err(_) => {
+                    return vote_auth_redirect(&state, &jar)
+                        .unwrap_or_else(|| login_redirect_js().into_response());
+                }
+            };
             if let Err(e) = state
                 .record_vote(&parent, &a, &b, ratio_left, ratio_right, &actor)
                 .await
diff --git a/server/src/auth/config.rs b/server/src/auth/config.rs
index a1f042c655bf3e5234eeb87a7d889f64592807fb..a5976af9a52ea207b35ae87bd1fe927c47a477ca 100644
--- a/server/src/auth/config.rs
+++ b/server/src/auth/config.rs
@@ -1,9 +1,42 @@
 pub const AUTH_RETURN_COOKIE: &str = "sorter2_auth_return";
 
+/// Allow `mock_user` on `/auth/github` (test harness only).
+pub fn mock_oauth_allowed() -> bool {
+    matches!(
+        std::env::var("SORTER2_ALLOW_MOCK_OAUTH").as_deref(),
+        Ok("1") | Ok("true") | Ok("TRUE")
+    )
+}
+
+/// Set the Secure flag on auth cookies when serving over HTTPS.
+pub fn cookies_secure() -> bool {
+    std::env::var("SORTER2_BASE_URL")
+        .map(|u| u.starts_with("https://"))
+        .unwrap_or(false)
+}
+
 pub fn sanitize_return_to(raw: &str) -> String {
     let s = raw.trim();
-    if s.is_empty() || !s.starts_with('/') || s.starts_with("//") {
+    if s.is_empty() || !s.starts_with('/') || s.starts_with("//") || s.starts_with("/\\") {
+        return "/".to_string();
+    }
+    // Reject scheme-relative and protocol-smuggling forms.
+    if s.contains("://") || s.contains('\\') {
         return "/".to_string();
     }
     s.to_string()
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn sanitize_return_to_blocks_open_redirects() {
+        assert_eq!(sanitize_return_to(""), "/");
+        assert_eq!(sanitize_return_to("//evil.com"), "/");
+        assert_eq!(sanitize_return_to("/\\evil.com"), "/");
+        assert_eq!(sanitize_return_to("https://evil.com"), "/");
+        assert_eq!(sanitize_return_to("/vote?parent=x"), "/vote?parent=x");
+    }
+}
diff --git a/server/src/auth/mod.rs b/server/src/auth/mod.rs
index 5ed535ba199fa736f0048c32623b14c3b1e5de2d..d4a85ef52c15dc35148e4c743f0d646cbbdb056d 100644
--- a/server/src/auth/mod.rs
+++ b/server/src/auth/mod.rs
@@ -26,7 +26,7 @@ use crate::{
     ui_action::UI_RPC_FIELD,
 };
 
-pub use session::{resolve_vote_actor, session_id_from_jar, VoteActor};
+pub use session::{nav_pseudonym, resolve_vote_actor, session_id_from_jar, VoteActor};
 
 pub fn base_url_from_env(port: u16) -> String {
     std::env::var("SORTER2_BASE_URL")
@@ -168,6 +168,10 @@ pub async fn login_page(
         "login · sorter2",
         login_body(session.as_ref(), &aliases, &providers),
         state.views.get_views("/login"),
+        session
+            .as_ref()
+            .filter(|s| !s.pseudonym.trim().is_empty())
+            .map(|s| s.pseudonym.as_str()),
     );
     (jar, Html(markup.into_string())).into_response()
 }
@@ -222,6 +226,7 @@ pub async fn alias_page(
             "choose alias · sorter2",
             body,
             state.views.get_views("/login/alias"),
+            None,
         )
         .into_string(),
     )
@@ -237,7 +242,12 @@ pub async fn github_start(
         .ok_or(StatusCode::SERVICE_UNAVAILABLE)?;
     let return_to = return_from_query_or_jar(&jar, query.return_to.as_deref());
     let state_token = session::new_oauth_state();
-    let url = oauth::authorize_url(&cfg, &state_token, query.mock_user.as_deref());
+    let mock_user = if config::mock_oauth_allowed() {
+        query.mock_user.as_deref()
+    } else {
+        None
+    };
+    let url = oauth::authorize_url(&cfg, &state_token, mock_user);
     let jar = jar
         .add(session::oauth_state_cookie_value(&state_token))
         .add(session::auth_return_cookie_value(&return_to));
diff --git a/server/src/auth/session.rs b/server/src/auth/session.rs
index 09659240b9455c6fca12db5652e1d31cf8c2acfc..41df030ded3abcafc0ab3887ab769adf103f9aa0 100644
--- a/server/src/auth/session.rs
+++ b/server/src/auth/session.rs
@@ -5,7 +5,7 @@ use durable::{Db, Durability};
 use rand::Rng;
 
 use crate::{
-    auth::config::AUTH_RETURN_COOKIE,
+    auth::config::{self, AUTH_RETURN_COOKIE},
     fetch::now_ms,
     identity::{DEFAULT_ACTOR_UUID, DEFAULT_PSEUDONYM},
     storage_dto::{SessionDataV1, SESSION_DATA_VERSION},
@@ -37,6 +37,7 @@ pub struct VoteActor {
 }
 
 impl VoteActor {
+    /// Test / bench helper: seed votes as the default pseudonym without a session.
     pub fn anon() -> Self {
         Self {
             pseudonym: DEFAULT_PSEUDONYM.to_string(),
@@ -70,20 +71,51 @@ fn hex_encode(bytes: &[u8]) -> String {
     bytes.iter().map(|b| format!("{b:02x}")).collect()
 }
 
-pub fn resolve_vote_actor(db: &Db, session_id: Option<&str>) -> VoteActor {
-    let Some(session_id) = session_id else {
-        return VoteActor::anon();
-    };
-    let Ok(Some(session)) = load_session(db, session_id) else {
-        return VoteActor::anon();
-    };
-    if session.expires_at <= now_ms() {
-        return VoteActor::anon();
+fn build_cookie(name: &'static str, value: String) -> Cookie<'static> {
+    let mut builder = Cookie::build((name, value))
+        .http_only(true)
+        .same_site(SameSite::Lax)
+        .path("/");
+    if config::cookies_secure() {
+        builder = builder.secure(true);
+    }
+    builder.build()
+}
+
+fn clear_cookie(name: &'static str) -> Cookie<'static> {
+    let mut builder = Cookie::build((name, ""))
+        .http_only(true)
+        .same_site(SameSite::Lax)
+        .path("/")
+        .removal();
+    if config::cookies_secure() {
+        builder = builder.secure(true);
+    }
+    builder.build()
+}
+
+/// Resolve the vote actor from a live session. Fail-closed: never falls back to anon.
+pub fn resolve_vote_actor(db: &Db, session_id: Option<&str>) -> Result<VoteActor, &'static str> {
+    let session_id = session_id.ok_or("sign in to vote")?;
+    let session = load_valid_session(db, session_id).ok_or("session expired")?;
+    if !session_has_pseudonym(&session) {
+        return Err("choose an alias first");
     }
     let trust_weight = user_trust_weight(db, &session.uuid).unwrap_or(1.0);
-    VoteActor {
+    Ok(VoteActor {
         pseudonym: session.current_pseudonym,
         trust_weight,
+    })
+}
+
+/// Display name for the top nav, if any session is active.
+pub fn nav_pseudonym(db: &Db, jar: &CookieJar) -> Option<String> {
+    let session_id = session_id_from_jar(jar)?;
+    let session = load_valid_session(db, &session_id)?;
+    if session_has_pseudonym(&session) {
+        Some(session.current_pseudonym)
+    } else {
+        None
     }
 }
 
@@ -151,54 +183,27 @@ pub fn destroy_session(db: &Db, session_id: &str) -> Result<(), String> {
 }
 
 pub fn session_cookie_value(session_id: &str) -> Cookie<'static> {
-    Cookie::build((SESSION_COOKIE, session_id.to_string()))
-        .http_only(true)
-        .same_site(SameSite::Lax)
-        .path("/")
-        .build()
+    build_cookie(SESSION_COOKIE, session_id.to_string())
 }
 
 pub fn clear_session_cookie() -> Cookie<'static> {
-    Cookie::build((SESSION_COOKIE, ""))
-        .http_only(true)
-        .same_site(SameSite::Lax)
-        .path("/")
-        .removal()
-        .build()
+    clear_cookie(SESSION_COOKIE)
 }
 
 pub fn oauth_state_cookie_value(state: &str) -> Cookie<'static> {
-    Cookie::build((OAUTH_STATE_COOKIE, state.to_string()))
-        .http_only(true)
-        .same_site(SameSite::Lax)
-        .path("/")
-        .build()
+    build_cookie(OAUTH_STATE_COOKIE, state.to_string())
 }
 
 pub fn clear_oauth_state_cookie() -> Cookie<'static> {
-    Cookie::build((OAUTH_STATE_COOKIE, ""))
-        .http_only(true)
-        .same_site(SameSite::Lax)
-        .path("/")
-        .removal()
-        .build()
+    clear_cookie(OAUTH_STATE_COOKIE)
 }
 
 pub fn auth_return_cookie_value(return_to: &str) -> Cookie<'static> {
-    Cookie::build((AUTH_RETURN_COOKIE, return_to.to_string()))
-        .http_only(true)
-        .same_site(SameSite::Lax)
-        .path("/")
-        .build()
+    build_cookie(AUTH_RETURN_COOKIE, return_to.to_string())
 }
 
 pub fn clear_auth_return_cookie() -> Cookie<'static> {
-    Cookie::build((AUTH_RETURN_COOKIE, ""))
-        .http_only(true)
-        .same_site(SameSite::Lax)
-        .path("/")
-        .removal()
-        .build()
+    clear_cookie(AUTH_RETURN_COOKIE)
 }
 
 pub fn auth_return_from_jar(jar: &CookieJar) -> Option<String> {
@@ -213,28 +218,35 @@ pub fn oauth_state_from_jar(jar: &CookieJar) -> Option<String> {
     jar.get(OAUTH_STATE_COOKIE).map(|c| c.value().to_string())
 }
 
-pub fn actor_uuid_for_vote(db: &Db, session_id: Option<&str>) -> String {
-    let Some(session_id) = session_id else {
-        return DEFAULT_ACTOR_UUID.to_string();
-    };
-    load_session(db, session_id)
-        .ok()
-        .flatten()
-        .filter(|s| s.expires_at > now_ms())
-        .map(|s| s.uuid)
-        .unwrap_or_else(|| DEFAULT_ACTOR_UUID.to_string())
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;
 
     #[test]
-    fn missing_session_falls_back_to_anon() {
+    fn missing_session_is_error() {
+        let dir = tempfile::tempdir().unwrap();
+        let db = Db::open(dir.path()).unwrap();
+        assert_eq!(resolve_vote_actor(&db, None).unwrap_err(), "sign in to vote");
+    }
+
+    #[test]
+    fn session_without_pseudonym_is_error() {
+        let dir = tempfile::tempdir().unwrap();
+        let db = Db::open(dir.path()).unwrap();
+        let (id, _) = create_session(&db, DEFAULT_ACTOR_UUID, "").unwrap();
+        assert_eq!(
+            resolve_vote_actor(&db, Some(&id)).unwrap_err(),
+            "choose an alias first"
+        );
+    }
+
+    #[test]
+    fn session_with_pseudonym_resolves() {
         let dir = tempfile::tempdir().unwrap();
         let db = Db::open(dir.path()).unwrap();
-        let actor = resolve_vote_actor(&db, None);
-        assert_eq!(actor.pseudonym, DEFAULT_PSEUDONYM);
+        let (id, _) = create_session(&db, DEFAULT_ACTOR_UUID, "alice").unwrap();
+        let actor = resolve_vote_actor(&db, Some(&id)).unwrap();
+        assert_eq!(actor.pseudonym, "alice");
         assert_eq!(actor.trust_weight, 1.0);
     }
 }
diff --git a/server/src/html/mod.rs b/server/src/html/mod.rs
index 46d18b87f1313bf0aeb29955d18f291961057509..3cc3d7bdf55b5cb5d009600f4ade1fcd201a410b 100644
--- a/server/src/html/mod.rs
+++ b/server/src/html/mod.rs
@@ -4,11 +4,13 @@ use axum::{
     http::{header, StatusCode, Uri},
     response::{IntoResponse, Response},
 };
+use axum_extra::extract::cookie::CookieJar;
 use maud::{html, Markup, DOCTYPE};
 
 use std::collections::HashSet;
 
 use crate::{
+    auth::nav_pseudonym,
     fetch::html::entity_section,
     form_template::template_json_compact,
     path_types::ItemId,
@@ -126,7 +128,7 @@ pub fn now_ms() -> i64 {
     t.as_millis() as i64
 }
 
-pub(crate) fn layout(title: &str, body: Markup, views: u64) -> Markup {
+pub(crate) fn layout(title: &str, body: Markup, views: u64, nav_user: Option<&str>) -> Markup {
     let ver = asset_version();
     let css_href = format!("/static/sorter.css?v={ver}");
     let js_src = format!("/static/sorter_ui.js?v={ver}");
@@ -145,7 +147,15 @@ pub(crate) fn layout(title: &str, body: Markup, views: u64) -> Markup {
                     span class="view-meta muted" { (views) " views" }
                 }
                 nav class="top-nav" {
-                    a href="/login" { "login" }
+                    @if let Some(name) = nav_user {
+                        span class="top-nav-user" data-testid="nav-user" { (name) }
+                        a href="/login" { "account" }
+                        form class="top-nav-logout" method="post" action="/auth/logout" data-navigate="full" {
+                            button type="submit" data-testid="nav-logout" { "log out" }
+                        }
+                    } @else {
+                        a href="/login" data-testid="nav-login" { "login" }
+                    }
                 }
                 div id="errors" {}
                 (body)
@@ -481,10 +491,11 @@ pub fn input_panel(query: &str, error: Option<&str>) -> Markup {
     }
 }
 
-async fn item_page(state: AppState, uri: Uri, item: ItemId) -> Markup {
+async fn item_page(state: AppState, uri: Uri, item: ItemId, jar: CookieJar) -> Markup {
     let path = uri.path().to_string();
     state.views.increment(path.clone());
     let views = state.views.get_views(&path);
+    let nav_user = nav_pseudonym(state.projection_store.db(), &jar);
 
     let tree = state
         .scope_tree(&item)
@@ -513,16 +524,24 @@ async fn item_page(state: AppState, uri: Uri, item: ItemId) -> Markup {
             (ranking_panel(&item, node, &tree))
         }
     };
-    layout("sorter2", body, views)
+    layout("sorter2", body, views, nav_user.as_deref())
 }
 
-pub async fn home(State(state): State<AppState>, uri: Uri) -> impl IntoResponse {
-    item_page(state, uri, ItemId::root()).await
+pub async fn home(
+    State(state): State<AppState>,
+    jar: CookieJar,
+    uri: Uri,
+) -> impl IntoResponse {
+    item_page(state, uri, ItemId::root(), jar).await
 }
 
-pub async fn browse(State(state): State<AppState>, uri: Uri) -> impl IntoResponse {
+pub async fn browse(
+    State(state): State<AppState>,
+    jar: CookieJar,
+    uri: Uri,
+) -> impl IntoResponse {
     let item = ItemId::from_browse_uri(uri.path()).unwrap_or(ItemId::root());
-    item_page(state, uri, item).await
+    item_page(state, uri, item, jar).await
 }
 
 #[cfg(test)]
diff --git a/server/src/html/vote.rs b/server/src/html/vote.rs
index 3aa00c417c89a9cab3417c650b50ed7c73f08e20..cadbec188b17a48a63b269c0e2fa2ea8ffedd7ed 100644
--- a/server/src/html/vote.rs
+++ b/server/src/html/vote.rs
@@ -4,11 +4,13 @@ use axum::{
     extract::{Query, State},
     response::{Html, IntoResponse},
 };
+use axum_extra::extract::cookie::CookieJar;
 use maud::{html, Markup};
 use serde::Deserialize;
 use std::collections::HashSet;
 
 use crate::{
+    auth::nav_pseudonym,
     fetch::html::entity_section,
     form_template::template_json_compact,
     html::{ranking_panel_with_highlights, scope_theme_style, JsBuilder},
@@ -262,6 +264,7 @@ fn suggest_next(
 
 pub async fn vote_page(
     State(state): State<AppState>,
+    jar: CookieJar,
     Query(q): Query<VoteQuery>,
 ) -> impl IntoResponse {
     let parent = parse_item_param(&q.parent);
@@ -329,8 +332,9 @@ pub async fn vote_page(
     let path = format!("/vote?parent={}", urlencoding::encode(parent.as_str()));
     state.views.increment(path.clone());
     let views = state.views.get_views(&path);
+    let nav_user = nav_pseudonym(state.projection_store.db(), &jar);
 
-    Html(layout(&title, body, views).into_string()).into_response()
+    Html(layout(&title, body, views, nav_user.as_deref()).into_string()).into_response()
 }
 
 #[cfg(test)]
diff --git a/server/static/sorter.css b/server/static/sorter.css
index e66a1e6c1acc473c8ff1ddb1e16e75a82d33741c..257280b6b490c65222e580a325b77351cac6cc6b 100644
--- a/server/static/sorter.css
+++ b/server/static/sorter.css
@@ -34,6 +34,47 @@ body {
   font-size: 0.75rem;
 }
 
+.top-nav {
+  display: flex;
+  align-items: center;
+  justify-content: flex-end;
+  gap: 0.75rem;
+  padding: 0.5rem 1rem;
+  font-size: 0.875rem;
+}
+
+.top-nav a {
+  color: var(--muted);
+  text-decoration: none;
+}
+
+.top-nav a:hover {
+  color: var(--fg);
+}
+
+.top-nav-user {
+  color: var(--fg);
+  font-weight: 600;
+}
+
+.top-nav-logout {
+  display: inline;
+  margin: 0;
+}
+
+.top-nav-logout button {
+  background: none;
+  border: none;
+  padding: 0;
+  color: var(--muted);
+  font: inherit;
+  cursor: pointer;
+}
+
+.top-nav-logout button:hover {
+  color: var(--fg);
+}
+
 .btn-primary {
   background: var(--accent);
   color: var(--accent-fg, #0f1115);
diff --git a/test/support/harness.clj b/test/support/harness.clj
index 3f05951f418258642dcacb4a10ccccc8bfbe8748..4505ece5aa193e826ca61c52f1467d252080d66b 100644
--- a/test/support/harness.clj
+++ b/test/support/harness.clj
@@ -43,6 +43,7 @@
          "SORTER2_VIEWS_LOG" (str data-dir "/views.jsonl")
          "PORT" (str app-port)
          "SORTER2_BASE_URL" (str "http://127.0.0.1:" app-port)
+         "SORTER2_ALLOW_MOCK_OAUTH" "1"
          "GITHUB_CLIENT_ID" "test-client"
          "GITHUB_CLIENT_SECRET" "test-secret"
          "GITHUB_OAUTH_BASE" (str "http://127.0.0.1:" oauth-port)


Side B — contributor: tommy-mor
Side B — commit message:
[c59951f5] fixed canonical item paths business

Side B — unified diff (full patch):
diff --git a/server/src/html/breadcrumb_path.rs b/server/src/html/breadcrumb_path.rs
index 12ad2c84faf2fbb693015d4552e45b5c54d587b9..c8a3937923161a6ff248bd77e87eff0dc6fe9ab0 100644
--- a/server/src/html/breadcrumb_path.rs
+++ b/server/src/html/breadcrumb_path.rs
@@ -1,4 +1,4 @@
-use crate::path_types::CanonicalItemUrl;
+use crate::path_types::{tilde_http_path_to_canonical, CanonicalItemUrl};
 
 /// Semantic view of an ontology path for rendering and routing decisions.
 pub(super) struct OntologyPath {
@@ -11,16 +11,7 @@ impl OntologyPath {
     /// Path is the `*path` segment from `/~/*path` (e.g. `topic/a`). Always treat it as under `~/`
     /// so it canonicalizes to `https://slug.social/~/…`, not the non-tilde site path.
     pub(super) fn from_input(path: &str) -> Self {
-        let p = path.trim_start_matches('/');
-        let raw = if p.starts_with("http://") || p.starts_with("https://") {
-            p.to_string()
-        } else if p.is_empty() {
-            "~/".to_string()
-        } else {
-            format!("~/{}", p)
-        };
-        let canonical = CanonicalItemUrl::parse(&raw)
-            .unwrap_or_else(|| CanonicalItemUrl::parse("~/").unwrap());
+        let canonical = tilde_http_path_to_canonical(path);
         Self::from_canonical(canonical)
     }
 
@@ -37,7 +28,7 @@ impl OntologyPath {
     }
 
     pub(super) fn root() -> Self {
-        Self::from_canonical(CanonicalItemUrl::parse("~/").unwrap())
+        Self::from_canonical(CanonicalItemUrl::ontology_root())
     }
 
     pub(super) fn is_root(&self) -> bool {
diff --git a/server/src/html/garden.rs b/server/src/html/garden.rs
index d58d9b46f575eb6b7e4971086b07dda75ca2f645..319feb15a6b68d2b5df98b4289fedbc9bdd048d3 100644
--- a/server/src/html/garden.rs
+++ b/server/src/html/garden.rs
@@ -459,6 +459,8 @@ struct ItemPageViewModel {
     item: String,
     body: Option<String>,
     sibling_rank: Option<SiblingRank>,
+    /// False at the tilde ontology root (`~/`): sibling-rank footnote does not apply.
+    item_has_parent: bool,
     child_rankings: ChildrenRankings,
     rank_history: Vec<RankHistoryEntryView>,
     /// Forum threads that mention or vote on this item.
@@ -470,11 +472,12 @@ fn build_sibling_rank(
     scope: &ScopeId,
     item: &CanonicalItemUrl,
 ) -> Option<SiblingRank> {
+    let item = item.clone().normalized_storage();
     let content = reduced
         .content_for_scope(scope)
         .unwrap_or_else(|| reduced.public());
     let group = &content.ranking_group;
-    let parent = item.parent()?;
+    let parent = item.parent()?.normalized_storage();
     let siblings: Vec<CanonicalItemUrl> = content
         .item_children
         .get(&parent)
@@ -492,7 +495,7 @@ fn build_sibling_rank(
     if scoped_idxs.is_empty() {
         return None;
     }
-    let current_idx = *group.item_to_idx.get(item)?;
+    let current_idx = *group.item_to_idx.get(&item)?;
     if !scoped_idxs.contains(&current_idx) {
         return None;
     }
@@ -520,7 +523,7 @@ fn build_sibling_rank(
         .filter_map(|li| local_to_global.get(*li).copied())
         .collect();
     let ranked = ranked_items_subset(group, &comp_global, 10000, 1e-8);
-    let position = ranked.iter().position(|r| &r.item == item)? + 1;
+    let position = ranked.iter().position(|r| r.item == item)? + 1;
     Some(SiblingRank {
         position,
         component_size: ranked.len(),
@@ -597,7 +600,9 @@ fn build_item_page_view_model(
         .content_for_scope(scope)
         .unwrap_or_else(|| reduced.public());
     let item_key = CanonicalItemUrl::parse(item)
-        .unwrap_or_else(|| CanonicalItemUrl::parse("~/").unwrap());
+        .unwrap_or_else(|| CanonicalItemUrl::parse("~/").unwrap())
+        .normalized_storage();
+    let item_has_parent = item_key.parent().is_some();
     let child_rankings = build_children_rankings(content, &item_key);
 
     let rank_history = build_rank_history(reduced, scope, item_key.as_str());
@@ -617,6 +622,7 @@ fn build_item_page_view_model(
             .cloned()
             .or_else(|| reduced.public().item_bodies.get(&item_key).cloned()),
         sibling_rank: build_sibling_rank(reduced, scope, &item_key),
+        item_has_parent,
         child_rankings,
         rank_history,
         threads,
@@ -652,7 +658,7 @@ async fn render_scope_view(
                             (format!("#{} of {}", rank.position, rank.component_size))
                         }
                         span class="muted" { (format!("({} siblings)", rank.sibling_total)) }
-                    } @else {
+                    } @else if model.item_has_parent {
                         span class="muted" { "unranked among siblings" }
                     }
                 }
@@ -815,6 +821,18 @@ mod tests {
         }));
     }
 
+    fn apply_ingest_room(state: &mut ReducerState, ts: i64, room_id: &str, raw: &str) {
+        state.apply_event(Event::Ingest(Ingest {
+            ts,
+            id: format!("ing-{ts}"),
+            raw: raw.to_string(),
+            principal: "testuser".to_string(),
+            delegate: Some("00000000-0000-0000-0000-000000000000:test:local/test".to_string()),
+            room_id: room_id.to_string(),
+            thread_tag: String::new(),
+        }));
+    }
+
     #[test]
     fn item_page_model_includes_body_and_unranked_without_votes() {
         let mut reduced = ReducerState::default();
@@ -885,4 +903,85 @@ mod tests {
                 || model.child_rankings.unranked_items.contains(&CanonicalItemUrl("https://slug.social/~/topic/kid2".to_string()))
         );
     }
+
+    #[test]
+    fn item_page_room_scope_root_lists_top_level_children() {
+        let mut reduced = ReducerState::default();
+        apply_ingest_room(
+            &mut reduced,
+            1,
+            "9ab12cd/my-room",
+            "@00000000-0000-0000-0000-000000000000:test:local/test\n~/t1 {a}\n~/t2 {b}\n",
+        );
+        use crate::path_types::CanonicalItemUrl;
+        let root = CanonicalItemUrl::ontology_root();
+        let model = build_item_page_view_model(
+            &reduced,
+            &ScopeId::Room("9ab12cd/my-room".to_string()),
+            root.as_str(),
+        );
+        assert!(!model.item_has_parent);
+        assert_eq!(model.child_rankings.unranked_items.len(), 2);
+        let set: std::collections::HashSet<&str> = model
+            .child_rankings
+            .unranked_items
+            .iter()
+            .map(|u| u.as_str())
+            .collect();
+        assert!(set.contains("https://slug.social/~/t1"));
+        assert!(set.contains("https://slug.social/~/t2"));
+    }
+
+    /// Top-level `~/a` vs `~/b` votes form one ranked component under the ontology root.
+    #[test]
+    fn item_page_room_scope_root_shows_ranked_child_group() {
+        let mut reduced = ReducerState::default();
+        apply_ingest_room(
+            &mut reduced,
+            1,
+            "9ab12cd/my-room",
+            "@00000000-0000-0000-0000-000000000000:test:local/test\n\
+             ~/a {a}\n~/b {b}\n~/a 2:1 ~/b {because}\n",
+        );
+        use crate::path_types::CanonicalItemUrl;
+        let root = CanonicalItemUrl::ontology_root();
+        let model = build_item_page_view_model(
+            &reduced,
+            &ScopeId::Room("9ab12cd/my-room".to_string()),
+            root.as_str(),
+        );
+        assert_eq!(model.child_rankings.component_rankings.len(), 1);
+        assert_eq!(model.child_rankings.component_rankings[0].pairs, 1);
+        let names: Vec<&str> = model.child_rankings.component_rankings[0]
+            .ranked
+            .iter()
+            .map(|r| r.item.as_str())
+            .collect();
+        assert_eq!(
+            names,
+            vec!["https://slug.social/~/a", "https://slug.social/~/b"]
+        );
+        assert!(model.child_rankings.unranked_items.is_empty());
+    }
+
+    /// Legacy `https://slug.social/~/` spelling still resolves children under the real root key.
+    #[test]
+    fn item_page_model_normalizes_legacy_tilde_root_storage_url() {
+        let mut reduced = ReducerState::default();
+        apply_ingest(
+            &mut reduced,
+            1,
+            "@00000000-0000-0000-0000-000000000000:test:local/test\n~/x {x}\n",
+        );
+        let model = build_item_page_view_model(
+            &reduced,
+            &ScopeId::Public,
+            "https://slug.social/~/",
+        );
+        assert_eq!(model.child_rankings.unranked_items.len(), 1);
+        assert_eq!(
+            model.child_rankings.unranked_items[0].as_str(),
+            "https://slug.social/~/x"
+        );
+    }
 }
diff --git a/server/src/path_types.rs b/server/src/path_types.rs
index 4c8075bbd488f1b9a5eda9e03ced83f6238c6d5e..361a9d446c9043cbdea5f060db2e8633c2fd9bf9 100644
--- a/server/src/path_types.rs
+++ b/server/src/path_types.rs
@@ -1,3 +1,5 @@
 //! Re-exports — implementations live in `slug-types` (`paths` module).
 
-pub use slug_types::paths::{CanonicalItemUrl, RelativePath, TildePath};
+pub use slug_types::paths::{
+    tilde_http_path_to_canonical, CanonicalItemUrl, RelativePath, TildeHttpPathTail, TildePath,
+};
diff --git a/server/src/scope_rank.rs b/server/src/scope_rank.rs
index dc640848232b7e79142bfeeea3003c9023f84854..d656b2f0a0a3623ca6b234b746beaaca8ae6017d 100644
--- a/server/src/scope_rank.rs
+++ b/server/src/scope_rank.rs
@@ -149,9 +149,10 @@ pub fn build_rankings_for_item_set(content: &ContentState, items_in_scope: &[Can
 /// Build connected-component rankings for direct children of parent_scope.
 /// Matches the HTML garden view: multiple components, isolates, no-vote items.
 pub fn build_children_rankings(content: &ContentState, parent: &CanonicalItemUrl) -> ChildrenRankings {
+    let parent = parent.clone().normalized_storage();
     let items: Vec<CanonicalItemUrl> = content
         .item_children
-        .get(parent)
+        .get(&parent)
         .map(|s| s.iter().cloned().collect())
         .unwrap_or_default();
     build_rankings_for_item_set(content, &items)
diff --git a/server/tests/integration.rs b/server/tests/integration.rs
index f9c218378f6a173e56ae1cec797b3c492986eac0..d4c5bfe9c6f1c71dc61878bd8c5e729b1b7c69ef 100644
--- a/server/tests/integration.rs
+++ b/server/tests/integration.rs
@@ -704,6 +704,62 @@ async fn test_private_room_post_links_use_private_garden_routes() {
     assert!(garden_body.contains(&format!("/r/{room_short}/{room_slug}/t/garden-thread")));
 }
 
+#[tokio::test]
+async fn test_private_room_garden_root_lists_top_level_tilde_children() {
+    let (addr, _tmp, _log, _handle) = create_test_server().await;
+    let client = reqwest::Client::builder()
+        .redirect(reqwest::redirect::Policy::none())
+        .build()
+        .unwrap();
+    let bearer = test_bearer();
+
+    let create = rpc_batch(
+        &client,
+        addr,
+        Some(&bearer),
+        serde_json::json!([{
+            "RoomCreate": { "slug": "garden-root-list" }
+        }]),
+    )
+    .await;
+    let room_id = create["results"][0]["result"]["RoomCreated"]["room_id"]
+        .as_str()
+        .unwrap()
+        .to_string();
+    let (room_short, room_slug) = room_id.split_once('/').unwrap();
+
+    let rpc = ui_post_ingest_rpc(
+        &room_id,
+        "ing",
+        "~/test1 {wow}\n~/test2 {wow2}\n~/test1 2:1 ~/test2 {because}\n",
+    );
+    let post = client
+        .post(format!("http://{addr}/ui"))
+        .header("Authorization", format!("Bearer {bearer}"))
+        .form(&[("__rpc__", rpc.as_str())])
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(post.status(), reqwest::StatusCode::OK);
+
+    let root_page = client
+        .get(format!("http://{addr}/r/{room_short}/{room_slug}/~"))
+        .header("Authorization", format!("Bearer {bearer}"))
+        .send()
+        .await
+        .unwrap();
+    assert!(root_page.status().is_success());
+    let body = root_page.text().await.unwrap();
+    assert!(
+        body.contains("ranked child groups"),
+        "expected garden child panel: {}",
+        body.len()
+    );
+    assert!(body.contains("~/test1"));
+    assert!(body.contains("~/test2"));
+    assert!(body.contains("ordering 1"));
+}
+
 #[tokio::test]
 async fn test_post_check_returns_targeted_js_error_for_missing_thread_tag() {
     let (addr, _tmp, _log, _handle) = create_test_server().await;
diff --git a/test/browser_public_garden.clj b/test/browser_public_garden.clj
new file mode 100644
index 0000000000000000000000000000000000000000..7bea08e1cf2c8f5b1a94b0640a46e9ba5607b19b
--- /dev/null
+++ b/test/browser_public_garden.clj
@@ -0,0 +1,100 @@
+(ns test.browser-public-garden
+  "Regression: ingest ontology items in the public room via RPC, then open /~ in the browser
+   and assert ranked + unranked paths appear (HTML garden index — not JSON API)."
+  (:require [babashka.fs :as fs]
+            [cheshire.core :as json]
+            [clojure.string :as str]
+            [clojure.test :refer [deftest is]]
+            [com.blockether.spel.core :as core]
+            [com.blockether.spel.locator :as locator]
+            [com.blockether.spel.page :as page]
+            [test.common :as common]
+            [test.oauth :as oauth]))
+
+(defn- wait-for-text [pg selector expected timeout-ms]
+  (let [deadline (+ (System/currentTimeMillis) timeout-ms)]
+    (loop []
+      (let [text (locator/text-content (page/locator pg selector))]
+        (if (and (string? text) (str/includes? text expected))
+          true
+          (if (< (System/currentTimeMillis) deadline)
+            (do (Thread/sleep 200) (recur))
+            false))))))
+
+(defn public-garden-flow! []
+  (println "\n━━━ browser public room garden index (RPC seed + GET /~) ━━━\n")
+
+  (common/letlocals
+   (bind build (common/run-cargo-build-release! ["slugsocial-server"]))
+   (is (zero? (:exit build)) "cargo build succeeds")
+   (bind server-bin "target/release/slugsocial-server")
+
+   (bind tmp-dir (str (fs/create-temp-dir {:prefix "slug-browser-pub-garden-"})))
+   (bind slug-port (common/pick-port))
+   (bind google-port (common/pick-port))
+   (bind base-url (str "http://127.0.0.1:" slug-port))
+   (bind google-url (str "http://127.0.0.1:" google-port))
+
+   (bind !server (atom nil))
+   (bind !google (atom nil))
+   (bind server-env (common/slug-server-env tmp-dir base-url google-url slug-port))
+   (try
+     (reset! !google (oauth/start-mock-google google-port
+                                              :google-users ["google-user-alice"]))
+     (reset! !server (common/start-server server-bin server-env))
+     (is (common/wait-for-server base-url 10000) "server responds to /healthz")
+
+     (let [alice-token (oauth/fetch-bearer-token! base-url :username "alice")
+           thread-tag "browser-pub-garden"
+           ;; Ranked pair at root + one isolate so both panels are exercised.
+           raw (str "# " thread-tag "\n\n"
+                    "~/br-pub-a {alpha}\n"
+                    "~/br-pub-b {beta}\n"
+                    "~/br-pub-c {gamma}\n"
+                    "~/br-pub-a 2:1 ~/br-pub-b {browser regression vote}\n")
+           post-resp (oauth/http-post-json
+                      (str base-url "/api/v0/rpc")
+                      [{"Post" {"room" "public"
+                                "thread_tag" thread-tag
+                                "text" raw
+                                "return_rank_diff" false}}]
+                      :headers {"Authorization" (str "Bearer " alice-token)})
+           post-json (json/parse-string (:body post-resp) false)
+           _ (is (true? (get-in post-json ["results" 0 "ok"])) "seed public post via rpc")
+           rank-resp (oauth/http-post-json
+                      (str base-url "/api/v0/rpc")
+                      [{"GetGardenRank" {"room" "public"
+                                         "parent_path" "~"
+                                         "depth" 1}}])
+           rank-json (json/parse-string (:body rank-resp) false)
+           _ (is (true? (get-in rank-json ["results" 0 "ok"])) "GetGardenRank ok")
+           comps (get-in rank-json ["results" 0 "result" "GardenRank" "components"])
+           _ (is (pos? (count comps)) "rank API reports at least one component")]
+       (core/with-playwright [pw]
+         (core/with-browser [browser (core/launch-chromium pw {:headless true :channel "chrome"})]
+           (core/with-context [ctx (core/new-context browser)]
+             (core/with-page [pg (core/new-page-from-context ctx)]
+               (page/navigate pg (str base-url "/login"))
+               (is (wait-for-text pg "body" "@alice" 15000) "alice session after login")
+               (page/navigate pg (str base-url "/~"))
+               (is (wait-for-text pg "body" "paths" 15000) "public garden index shows paths heading")
+               (is (wait-for-text pg "body" "ordering" 10000)
+                   "ranked child group meta visible")
+               (is (wait-for-text pg "body" "~/br-pub-a" 10000) "ranked list shows ~/br-pub-a")
+               (is (wait-for-text pg "body" "~/br-pub-b" 10000) "ranked list shows ~/br-pub-b")
+               (is (wait-for-text pg "body" "unranked" 10000) "unranked section present")
+               (is (wait-for-text pg "body" "~/br-pub-c" 10000)
+                   "unranked list shows ~/br-pub-c"))))))
+
+     (finally
+       (when-some [s @!server] (common/kill-server s))
+       (when-some [g @!google] ((:stop-fn g)))
+       (fs/delete-tree tmp-dir)))
+
+   nil))
+
+(defn public-garden-browser-test [& _args]
+  (public-garden-flow!))
+
+(deftest browser-public-garden-index-check
+  (public-garden-flow!))
diff --git a/tests.edn b/tests.edn
index 56fdfa4f29383ad305fd8068783e4efe2ed334a0..6e96432ba766461b4233c75dc48db2633483e5e0 100644
--- a/tests.edn
+++ b/tests.edn
@@ -16,7 +16,8 @@
    :ns-patterns ["^test\\.browser-sse$"
                  "^test\\.browser-ui-morph$"
                  "^test\\.browser-post-redact$"
-                 "^test\\.browser-room-delete$"]
+                 "^test\\.browser-room-delete$"
+                 "^test\\.browser-public-garden$"]
    :kaocha.filter/skip-meta [:skip]
    :parallel? false}]
  :plugins [:kaocha.plugin/junit-xml]
diff --git a/types/src/lib.rs b/types/src/lib.rs
index 8cea90238ef6207d65ecdb2903b8958fafb213d2..edbb923e4d7d41ad82dfc254c3bd697562383527 100644
--- a/types/src/lib.rs
+++ b/types/src/lib.rs
@@ -4,8 +4,9 @@ pub mod paths;
 pub mod timeago;
 
 pub use paths::{
-    canonicalize_item, canonicalize_tag, item_parent_path, item_path_segments, CanonicalItemUrl,
-    ForumThreadUrl, GardenItemUrl, RelativePath, TildeOntologyPath, TildePath,
+    canonicalize_item, canonicalize_tag, item_parent_path, item_path_segments, normalize_slug_ontology_storage_url,
+    CanonicalItemUrl, ForumThreadUrl, GardenItemUrl, RelativePath, SLUG_TILDE_ONTOLOGY_ROOT,
+    TildeHttpPathTail, TildeOntologyPath, TildePath, tilde_http_path_to_canonical,
 };
 
 /// Max characters returned for a garden item body unless `full=true` / `--full` (API + CLI).
diff --git a/types/src/paths.rs b/types/src/paths.rs
index 668323ed777f360f2838a0dfe6eae68905d1183b..8971f599a7ebcf399f60c306d35ee28d0f581194 100644
--- a/types/src/paths.rs
+++ b/types/src/paths.rs
@@ -1,5 +1,13 @@
 //! Canonical paths, storage ids, and JSON href newtypes. All normalization and
 //! room-aware URL rules for items live here.
+//!
+//! ## String kinds (parse in this module only)
+//!
+//! - **[`canonicalize_item`] / [`CanonicalItemUrl`]** — graph storage key and DSL form; tilde
+//!   ontology root is always [`SLUG_TILDE_ONTOLOGY_ROOT`] (no `…/~/` trailing slash only).
+//! - **[`TildeHttpPathTail`]** — capture from `GET /~/*path` or `…/r/…/~/…` (the `*path` segment).
+//! - **`-/…` wire form** — external items; see [`canonicalize_item`] dash branch.
+//! - **[`GardenItemUrl`], [`ForumThreadUrl`]** — JSON / browser href surfaces.
 
 use std::borrow::Borrow;
 use std::fmt;
@@ -7,6 +15,23 @@ use std::ops::Deref;
 
 use serde::{Deserialize, Serialize};
 
+// ---------------------------------------------------------------------------
+// Slug tilde ontology (single storage form for `~/`)
+// ---------------------------------------------------------------------------
+
+/// Canonical absolute URL for the tilde ontology **root** (`~/` in UI). Used as the
+/// `item_children` parent key for top-level items and must match [`CanonicalItemUrl::ontology_root`].
+pub const SLUG_TILDE_ONTOLOGY_ROOT: &str = "https://slug.social/~";
+
+/// Collapse legacy or parser variants of the ontology root to [`SLUG_TILDE_ONTOLOGY_ROOT`].
+pub fn normalize_slug_ontology_storage_url(s: &str) -> String {
+    if s == "https://slug.social/~/" {
+        SLUG_TILDE_ONTOLOGY_ROOT.to_string()
+    } else {
+        s.to_string()
+    }
+}
+
 // ---------------------------------------------------------------------------
 // Normalization (moved from server `canonical_path`)
 // ---------------------------------------------------------------------------
@@ -89,6 +114,9 @@ pub fn canonicalize_item(input: &str) -> String {
         .join("/");
 
     if is_tilde {
+        if tail.is_empty() {
+            return SLUG_TILDE_ONTOLOGY_ROOT.to_string();
+        }
         format!("https://slug.social/~/{}", tail)
     } else if tail.is_empty() {
         "https://slug.social".to_string()
@@ -173,7 +201,7 @@ impl CanonicalItemUrl {
         if c.is_empty() {
             None
         } else {
-            Some(Self(c))
+            Some(Self(normalize_slug_ontology_storage_url(&c)))
         }
     }
 
@@ -181,8 +209,19 @@ impl CanonicalItemUrl {
         &self.0
     }
 
+    /// Collapses legacy slug ontology root spellings so [`HashMap`] keys match the reducer graph.
+    pub fn normalized_storage(self) -> Self {
+        Self(normalize_slug_ontology_storage_url(self.as_str()))
+    }
+
     pub fn tilde_tail(&self) -> Option<&str> {
-        self.0.strip_prefix("https://slug.social/~/")
+        if let Some(tail) = self.0.strip_prefix("https://slug.social/~/") {
+            return Some(tail);
+        }
+        if self.0 == SLUG_TILDE_ONTOLOGY_ROOT || self.0 == "https://slug.social/~/" {
+            return Some("");
+        }
+        None
     }
 
     pub fn last_segment(&self) -> &str {
@@ -193,7 +232,7 @@ impl CanonicalItemUrl {
     }
 
     pub fn ontology_root() -> Self {
-        Self("https://slug.social/~".to_string())
+        Self(SLUG_TILDE_ONTOLOGY_ROOT.to_string())
     }
 
     pub fn parent(&self) -> Option<Self> {
@@ -234,9 +273,13 @@ impl CanonicalItemUrl {
 
     /// `-/` representation for external `https://…` items, `~/…` for slug ontology, else unchanged.
     pub fn display_path(&self) -> String {
-        if let Some(tail) = self.0.strip_prefix("https://slug.social/~/") {
-            format!("~/{}", tail)
-        } else if let Some(tail) = self.0.strip_prefix("https://") {
+        if let Some(tail) = self.tilde_tail() {
+            if tail.is_empty() {
+                return "~/".to_string();
+            }
+            return format!("~/{}", tail);
+        }
+        if let Some(tail) = self.0.strip_prefix("https://") {
             if tail.starts_with("slug.social") {
                 self.0.clone()
             } else {
@@ -276,6 +319,37 @@ impl CanonicalItemUrl {
     }
 }
 
+/// HTTP route capture: path segment after `~/` in `GET /~/*path` or `…/r/…/~/…` (empty = ontology root).
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct TildeHttpPathTail(pub String);
+
+impl TildeHttpPathTail {
+    pub fn new(path_segment: &str) -> Self {
+        Self(path_segment.trim_start_matches('/').to_string())
+    }
+
+    pub fn as_str(&self) -> &str {
+        &self.0
+    }
+
+    pub fn to_canonical(&self) -> CanonicalItemUrl {
+        tilde_http_path_to_canonical(self.as_str())
+    }
+}
+
+/// Map the router's tilde tail (e.g. `topic/a`, or empty for root) to a [`CanonicalItemUrl`].
+pub fn tilde_http_path_to_canonical(path_segment: &str) -> CanonicalItemUrl {
+    let p = path_segment.trim_start_matches('/');
+    let raw = if p.starts_with("http://") || p.starts_with("https://") {
+        p.to_string()
+    } else if p.is_empty() {
+        "~/".to_string()
+    } else {
+        format!("~/{}", p)
+    };
+    CanonicalItemUrl::parse(&raw).unwrap_or_else(|| CanonicalItemUrl::ontology_root())
+}
+
 impl fmt::Display for CanonicalItemUrl {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         self.0.fmt(f)
@@ -557,6 +631,44 @@ mod tests {
     fn canonical_parent_root_is_none() {
         let root = CanonicalItemUrl::parse("~/").unwrap();
         assert!(root.parent().is_none());
+        assert_eq!(root.as_str(), SLUG_TILDE_ONTOLOGY_ROOT);
+        assert_eq!(root, CanonicalItemUrl::ontology_root());
+    }
+
+    #[test]
+    fn tilde_ontology_root_unifies_forms() {
+        assert_eq!(canonicalize_item("~/"), SLUG_TILDE_ONTOLOGY_ROOT);
+        assert_eq!(
+            normalize_slug_ontology_storage_url("https://slug.social/~/"),
+            SLUG_TILDE_ONTOLOGY_ROOT.to_string()
+        );
+        assert_eq!(
+            CanonicalItemUrl::parse("https://slug.social/~/")
+                .unwrap()
+                .as_str(),
+            SLUG_TILDE_ONTOLOGY_ROOT
+        );
+        let legacy = CanonicalItemUrl("https://slug.social/~/".to_string());
+        assert_eq!(legacy.normalized_storage().as_str(), SLUG_TILDE_ONTOLOGY_ROOT);
+    }
+
+    #[test]
+    fn tilde_http_path_tail_maps_router_segment() {
+        assert_eq!(
+            TildeHttpPathTail::new("").to_canonical(),
+            CanonicalItemUrl::ontology_root()
+        );
+        assert_eq!(
+            tilde_http_path_to_canonical("topic/x").as_str(),
+            "https://slug.social/~/topic/x"
+        );
+    }
+
+    #[test]
+    fn display_path_slug_ontology_root() {
+        let r = CanonicalItemUrl::ontology_root();
+        assert_eq!(r.display_path(), "~/");
+        assert_eq!(r.tilde_tail(), Some(""));
     }
 
     #[test]