diff --git a/docs/adhoc/2026-05-03-sidebar-nav-and-bugfixes.md b/docs/adhoc/2026-05-03-sidebar-nav-and-bugfixes.md
new file mode 100644
index 0000000..71fd5c9
--- /dev/null
+++ b/docs/adhoc/2026-05-03-sidebar-nav-and-bugfixes.md
@@ -0,0 +1,139 @@
+---
+date: 2026-05-03
+author: tegwick (Claude Sonnet 4.6 pair)
+type: adhoc
+tags: [ui, navigation, bugfix, profiling]
+commits: 6078c48, 08d662d, e8b0c7c
+---
+
+# Session: Registry Bugfixes + Left Sidebar Navigation
+
+## What was done
+
+### Bug fixes (commit 6078c48)
+
+**Registry pages crashed on load** (`/WidgetTypeRegistry` and the three sibling tabs).
+Root cause: `IHP.NameSupport`'s Megaparsec-based runtime parser chokes on field names
+that end with a trailing underscore (e.g. `"label_"`). IHP generates `label_` as the
+Haskell record field name for the `label` SQL column to avoid shadowing the HTML `<label>`
+element. The parser accepts `label` but then fails when it encounters the trailing `_`.
+
+Affected call sites:
+- `orderByAsc #label_` in `Web/Controller/TypeRegistries.hs` (4×) and
+  `Web/Controller/Api/V2/Registries.hs` (3×) — crashes on page load
+- `textField #label_` in 4 view files — would crash on New/Edit form render
+
+Fix: `orderByAsc #name` everywhere (semantically equivalent for these registries);
+manual `<input name="label_">` replacing `textField #label_` in forms.
+`fill @'["label_"]`, `validateField #label_`, and `createRecord`/`updateRecord`
+are NOT affected — they use explicit `columnNames` from generated types or HTTP
+param names, bypassing NameSupport.
+
+**Logout returned 500** (`UnexpectedMethodException {allowedMethods = [DELETE], method = GET}`).
+The nav `<a href={DeleteSessionAction}>` issues a GET, but IHP routes `DeleteSessionAction`
+as DELETE. IHP ships `Network.Wai.Middleware.MethodOverridePost` in its middleware stack.
+Fix: replace the `<a>` with a POST form carrying `<input type="hidden" name="_method" value="DELETE">`.
+
+**Seed migration had wrong password hash format.**
+`Application/Migration/1744416000-seed-admin-user.sql` used a bcrypt hash (`$2b$10$…`).
+IHP's `verifyPassword` uses `Crypto.PasswordStore.verifyPassword` from `pwstore-fast`,
+which produces and consumes PBKDF2-SHA256 hashes in the format `sha256|17|<b64salt>|<b64hash>`.
+The formats are incompatible. Fixed the migration; added a "Password Hashing" section to
+`deploy/railiance/RUNBOOK.md` with a runghc snippet for generating correct hashes on haskelseed.
+
+### UI change: left sidebar navigation (commits 08d662d, e8b0c7c)
+
+Moved all operational links out of a flat top nav (which was overflowing on any screen)
+into a grouped left sidebar (192 px wide). Top nav retains: logo (left) and
+About / Tutorial / Extend / Sign out (right).
+
+Sidebar groups:
+| Group | Links |
+|---|---|
+| *(top, ungrouped)* | Hubs, Widgets |
+| Governance | Candidates, Requirements, Decisions, Deployments |
+| Intelligence | Agent Proposals, Agents, Routing, Collective, AI Gov, Learning |
+| Platform | Adapters, Propagations, Ops Review, Federation, Policies, Archive |
+| Registry | Registries, Extensions |
+| API & Market | API Consumers, API Dashboard, Hub Registry, Marketplace |
+
+**Follow-up fix (e8b0c7c):** `flex-col` and `flex-1` were absent from the compiled
+`prod.css`. Tailwind's build only bundles classes that appear in templates at compile time;
+these were new to the codebase. Without `flex-col`, the body defaulted to `flex-row`,
+placing the top nav beside the sidebar instead of above it. Fixed by replacing
+layout-structural Tailwind classes with inline styles (`style="display:flex;flex-direction:column"`)
+so the column layout is independent of the CSS bundle. Visual Tailwind classes (colors,
+spacing, hover states) remain as-is.
+
+---
+
+## Profiling results
+
+All times are wall-clock, measured between commit push and `kubectl rollout` completion.
+
+| Phase | Bug-fix build | Sidebar build | Layout-fix build |
+|---|---|---|---|
+| Code edit | ~25 min (diagnosis + 12 edits) | ~8 min (1 file) | ~5 min (1 file, 4 lines) |
+| Commit + push to Gitea | <1 min | <1 min | <1 min |
+| `nix build .#docker` on haskelseed | ~37 min | ~46 min | ~46 min (in progress) |
+| `skopeo` push to Gitea registry | ~1 min | ~1 min | ~1 min |
+| `kubectl set image` + rollout | ~2 min | ~2 min | ~2 min |
+| **Total** | **~66 min** | **~58 min** | **~55 min** |
+
+The Nix build dominates in every case. A 4-line change costs the same as a 50-line change.
+
+---
+
+## Improvement suggestions
+
+### 1. Dev-loop: GHCi hot-reload for template changes (highest impact)
+
+The 46-minute build cycle is entirely driven by GHC recompiling the full app layer via
+Nix. In the `devenv` environment, `ghcid` reloads only changed modules in ~10–60 seconds.
+The current production pipeline skips `devenv` entirely.
+
+**Proposal:** Use the existing `devenv` + `ghcid` setup for all iterative work (including
+layout changes), test locally, then trigger a single `nix build` only when a feature is
+ready to ship. This reduces the effective iteration cycle from 46 min to 1–2 min for
+UI/template work.
+
+### 2. Nix binary cache for the app layer
+
+Each `nix build` on haskelseed rebuilds `inter-hub-lib-0.1.0.drv` from scratch because
+Nix detects a new input hash whenever any source file changes. A Nix binary cache
+(e.g. `cachix`) would allow haskelseed to upload build outputs and reuse them across
+machines, but would not help with incremental rebuilds on the same machine since the
+derivation hash changes per-commit.
+
+Partial improvement: configure Nix to use a remote builder with a warm store so that
+unchanged dependencies (IHP framework, GHC) are never fetched twice.
+
+### 3. Split the Haskell package into stable-lib + app layers
+
+Currently `inter-hub-lib` contains everything: IHP framework wiring AND all controllers
+and views. A single-file change causes the entire ~199-module package to recompile.
+
+**Proposal:** Extract a stable `inter-hub-core` package (models, types, helpers) and
+keep a thin `inter-hub-app` package (controllers, views, FrontController). Nix would
+then only rebuild `inter-hub-app` for UI/controller changes, leaving `inter-hub-core`
+cached. Estimated saving: 20–30 min per UI-only change.
+
+### 4. Tailwind CSS: safelist layout primitives
+
+Layout-structural Tailwind classes (`flex-col`, `flex-1`, `min-h-screen`, `grid-cols-*`)
+are frequently needed but may be absent from the compiled CSS if they haven't been used
+before. Workaround (current): inline styles. Proper fix: add a `safelist` entry in
+`tailwind.config.js` for layout utilities, or maintain a CSS file with layout primitives
+that is always included regardless of template scanning.
+
+### 5. IHP NameSupport — avoid trailing-underscore fields
+
+IHP generates `label_` (trailing underscore) for columns named `label` to avoid shadowing
+the HSX `<label>` element. The NameSupport runtime parser cannot handle the trailing
+underscore in query positions (`orderByAsc`, `filterWhere`, `textField`). This is an IHP
+v1.5 bug. Two mitigations until it is fixed upstream:
+
+- **Rename columns** at the schema level to avoid IHP-reserved words (`label` → `display_label`,
+  `type` → `entry_type`, etc.). Requires a migration but permanently removes the fragility.
+- **Avoid `textField`/`orderByAsc` with underscore fields**; use raw inputs and order by a
+  non-conflicting field (`#name`). This is the current workaround.