Beam component roadmap — plumb-ready list

Date: 2026-07-21 Status: backlog distilled from the day’s landings, minings, and blueprints (ide-workflows.md, attention-layer.md, ../acp/mission-plans.md). Every entry names its data source and whether that source EXISTS — the list is ordered so nothing waits on undesigned backend work.

Tier 0 — landed or in flight today (finish line, not backlog)

• UnitStatus composed-status atoms (landed) — the one truth for process × verdict × liveness × blocker, used by board/missions/inbox. The designated extension point for plan-progress and attention badges.
• Plan panel + step-progress fragment (in flight) — Mission.Plan on the mission API; checklist chips, revision + explanation line.
• Session adoption (in flight) — “Sitzung öffnen” from board/mission into the chat surface; übernommen/beobachten header; delete-guard; durability notice. Wire contract landed server-side.
• Fleet board / missions / inbox operability (landed) — running-first board, triage inbox, mobile + house patterns.

Tier 1 — API already exists, pure frontend (days, start anytime)

1. Workspace picker — source: GET /workspace/roots (landed today). Components: root chip in explorer/dispatch/chat headers; root selector on the dispatch form and new-chat flow (ACP session/new cwd already carries it); “outside roots” designed refusal state replacing the raw 422.
2. Terminal tab — source: terminalapi WS (fully built: PTY, reattach, in-band resize). xterm.js + fit addon, bolt.diy’s bridge verbatim. Blocked only on the interactivity decision (interactive vs read-only — flagged in ide-workflows.md).
3. Mission inspector shell — no backend at all: flat tab bar + OpenHands’ ~80-line resizable-split hook on MissionDetailPage, hosting Changes/Search/Terminal/Transcript tabs as they land. Hours.

The instant-feel law (binding on every tier)

The editors that won without being IDEs won on: instant latency, fuzzy-everything navigation over dumb text, zero ceremony (the folder is the project), shell composability, and plain-state honesty — while Eclipse-era IDEs traded the inner loop away for a semantic model. VS Code resolved it with progressive semantic enhancement: instantly usable dumb-fast, the model arrives async as an upgrade, never a prerequisite. Beam follows that resolution: every view works at record-speed over plain state (board, inbox, rg-streamed search — no index); the semantic layer (DOI ranking, plans, landed-vs-planned) is asynchronous enhancement that never blocks, gates, or delays the basic view.

3b. Goto-anything palette (Tier 1½, no backend gap — data all served already): a command palette fuzzy-matching over missions, agents, sessions, workspace roots, inbox items, and page actions. Keyboard-first, zero taxonomy (blind-spot compliant), the single biggest inner-loop upgrade per line of code the editors’ history offers. Size: ~1d.

Tier 2 — small named backend gap + frontend (the flagship arc)

4. Changed-files list + DiffViewer — the state-diff bet. Backend gap (small, designed): aggregate the per-edit ToolCallContent{Diff, Path, OldText, NewText} already flowing in acpsvc events into GET /missions/{id}/changes + /changes/diff?path=. Frontend: Monaco DiffEditor, collapsed rows, lazy per-file fetch, old/diff/new toggle, incomplete-suppression for huge files. First DOI hook: order the list by per-path edit/read counts (upgrade path in attention-layer.md).
5. Search panel — backend gap (small, designed): rg --json under the workspace root streamed as SSE/NDJSON. Frontend: bolt.diy’s Search.tsx anatomy (debounce, per-file groups, count badges, highlighted preview); click-through into #4’s diff when the hit is a changed file.
6. Plan-revision feed in the inbox — backend gap (small, needs a decision): plan_revised/status_changed are bus events with no REST history. Either (a) render only current Plan.{Revision, Explanation} on mission rows (zero backend), or (b) persist last-N revision summaries on the mission record for a real “+2/−1 — why” feed. (b) is the honest overnight-skim answer; size ~0.5d.

Tier 3 — rides on the attention layer (attention-layer.md)

7. Attention badges — “concentrated in 3 files / wandered 14 dirs” chips on board rows and inbox groups, from the same per-path aggregation as #4.
8. Scope-anomaly flag — the derailment early-warning (“unit left its expected scope”) as a first-class UnitStatus atom + inbox condition.
9. Transcript anchors — jump-to-where-attention-concentrated markers in the adopted-session view and journal rendering.

Tier 4 — post-decision / post-dependency

10. Batch/plan roll-up view — parent mission with children grouped (ParentSessionID exists; waits on the sub-mission/a2a slice).
11. Inline risk annotations — envelope/gate decisions rendered beside actions in transcript and timeline (OpenHands’ security_risk pattern); waits on events carrying the gate verdicts explicitly.
12. Checkpoint/rollback affordances — waits on the state-diff design maturing (see attention-layer.md and the beam criterion).

Deliberately absent (the meaningful-filter): text editing, LSP anything, debugging, embedded editor iframes, docking layouts.