Merge pull request 'fix: NEXT TURN button into the right pane — full width, no longer overlapped (#52, v0.14.0)' (#54) from feat/next-turn-button into master

- resolveJumpTask: build existingEdgeKeys from all jump routes (both
  endpoints in the save's system set), pass all systems except the
  target as attachCandidates, insert closing routes for each attach.
- save.test.ts: jump test now expects 1–4 fresh systems (was pinned
  to exactly 4); A/B snapshot test stays green (both paths share the
  same resolveJumpTask code).
- e2e/helpers.ts: update stale comment ('4 fresh neighbours' →
  '1–4 new systems').
- e2e/smoke.spec.ts: new test verifying 1–4 mints, all undiscovered,
  each routed to the target, and BFS connectivity of the full graph.

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## v0.14.0 — 2026-10-06 12:50
+- The NEXT TURN button now lives inside the right pane (full width of the pane, larger) instead of floating as a fixed bottom-right overlay — it can no longer be covered by the active-tasks strip (#52).
+- The button grew from the SM to the MD size and spans the whole pane content width; it pins to the pane bottom when the content is short and scrolls with it when the cargo list is long. The `TURN <n>` counter, the EXEC styling and the in-flight behaviour are unchanged.
+- E2E: new spec pins the button full-width in the right pane (≥ 280px, within ±8px of the CARGO HOLD panel) and asserts its bounding box does not intersect the active-tasks strip's while a task is queued.
+
+## v0.13.0 — 2026-10-06 12:17
+- Jump spread limit (#51): jumping into an undiscovered system now mints a seeded-random 1–4 new systems (was a fixed 4). Each leg can instead attach an already-known system (closing a loop) with probability 0.35, so the chart grows slower and more circular. A frontier guarantee ensures at least one new system is always minted.
+- `ringEdges` small-n fix: n=1 no longer emits a `[1,1]` self-loop, n=2 no longer emits a duplicate edge. n≥3 output is byte-identical to the legacy wheel.
+- `generateRing` gains `attachCandidates`, `existingEdgeKeys`, and `anchorId` parameters; `RingRegion` gains an `attaches` field. The `EXPAND_RING` constant is removed in favour of `EXPAND_MIN`/`EXPAND_MAX`.
+
 ## v0.12.0 — 2026-10-04 21:04
 - FINDS HIDDEN THINGS now grants +1 exploration haul item — one extra roll on the save's seeded per-planet stream, appended to the scan's haul.
 - TALKS TO ANYONE now raises the crew-recruit chance from 18% to 30% when a member with the trait is on the exploring team.

components/mission-control.tsx

@@ -529,6 +529,14 @@ export function MissionControl() {
                 )}
               </PanelContent>
             </Panel>
+
+            {/* #52 — the manual tick control (5b), moved in from the fixed bottom-right overlay:
+                last child of the pane's flex column — full width, size MD, pinned to the pane
+                bottom when the content is short (the wrapper's marginTop:auto) and scrolling
+                with the pane when the cargo list is long. In normal flow, the active-tasks strip
+                can no longer paint over it; the pane (unlike the tab content) is outside Radix's
+                unmount, so it stays visible on every tab. */}
+            <NextTurnButton turn={ship?.turn ?? null} onTicked={refreshAll} />
           </div>
         </div>
       </div>
@@ -567,13 +575,9 @@ export function MissionControl() {
         <Badge variant="ACTIVE">SYS ONLINE</Badge>
       </footer>
 
-      {/* #44 — the manual tick control (5b): fixed bottom-right, outside the tab grid so it
+      {/* #44 — the active-tasks strip: fixed bottom-left, outside the tab grid so it stays
-          stays visible on every tab (Radix unmounts inactive tabs — the button only refreshes
+          visible on every tab. (#52 moved the NEXT TURN button out of this fixed-overlay area
-          the snapshots this shell owns) */}
+          and into the right pane, so the two can no longer overlap.) Data: the shell's system
-      <NextTurnButton turn={ship?.turn ?? null} onTicked={refreshAll} />
-
-      {/* #44 — the active-tasks strip: fixed bottom-left (same mount convention as the button —
-          outside the tab grid so it stays visible on every tab). Data: the shell's system
           snapshot (JC-15) — refreshAll re-runs /api/system on every turn, so it updates on
           every shell refresh with no fetch of its own. */}
       <TaskStrip tasks={system?.tasks ?? []} />

components/next-turn-button.tsx

@@ -3,12 +3,16 @@
 import { useState } from 'react'
 import { Button } from '@/components/ui/button'
 
-// NEXT TURN — the manual tick control (5b): a fixed bottom-right button + the current turn from
+// NEXT TURN — the manual tick control (5b): a normal-flow block in the right pane (#52) carrying
-// the ship snapshot the shell holds. One click = POST /api/turn (no body); on success the shell
+// the current turn from the ship snapshot the shell holds. One click = POST /api/turn (no body);
-// re-fetches its snapshots. Review Focus 4: the button is NEVER disabled by game state — an
+// on success the shell re-fetches its snapshots. Review Focus 4: the button is NEVER disabled by
-// empty queue is a FREE SKIP (the route always returns 200) — and the only transient is an
+// game state — an empty queue is a FREE SKIP (the route always returns 200) — and the only
-// in-flight request, which the handler ignores. `disabled` is never set, so the cva
+// transient is an in-flight request, which the handler ignores. `disabled` is never set, so the
-// disabled:opacity-40 styling never applies either.
+// cva disabled:opacity-40 styling never applies either.
+// #52 — the fixed bottom-right overlay became the right pane's last flex child (mission-control):
+// full width, size MD, pinned to the pane bottom when the content is short (marginTop:auto) and
+// scrolling with the pane when the cargo list is long. No position/zIndex any more — so the
+// active-tasks strip can no longer paint over it.
 
 export function NextTurnButton({ turn, onTicked }: { turn: number | null; onTicked: () => void }) {
   const [inFlight, setInFlight] = useState(false)
@@ -30,14 +34,11 @@ export function NextTurnButton({ turn, onTicked }: { turn: number | null; onTick
   return (
     <div
       style={{
-        position: 'fixed',
-        right: '1rem',
-        bottom: '1rem',
-        zIndex: 60, // above the header/footer's 50
         display: 'flex',
         flexDirection: 'column',
-        alignItems: 'flex-end',
+        gap: '0.5rem',
-        gap: '0.375rem',
+        width: '100%',
+        marginTop: 'auto',
       }}
     >
       {error && (
@@ -46,7 +47,7 @@ export function NextTurnButton({ turn, onTicked }: { turn: number | null; onTick
       <span style={{ fontSize: '0.62rem', color: 'var(--text-muted)', letterSpacing: '0.12em' }}>
         TURN {turn ?? '—'}
       </span>
-      <Button variant="EXEC" size="SM" onClick={tick}>
+      <Button variant="EXEC" size="MD" className="w-full" onClick={tick}>
         NEXT TURN
       </Button>
     </div>

components/task-strip.tsx

@@ -2,7 +2,8 @@
 
 import type { QueueDto } from '@/lib/game/save'
 
-// TASK STRIP — the save's task queue, fixed bottom-left next to the NEXT TURN button (#44).
+// TASK STRIP — the save's task queue, fixed bottom-left (#44); the NEXT TURN button moved into
+// the right pane in #52, so the two can no longer overlap.
 // The array arrives pre-ordered from the snapshot builder (Task 6: ACTIVE block, then PENDING
 // block, each by (queuedAtTurn, id)) — the strip renders it as-is, dimming the PENDING rows,
 // and never fetches or re-sorts. Empty queue → null, no box at all. The shell re-renders it on

e2e/helpers.ts

@@ -49,12 +49,13 @@ export async function resolveAction(page: Page, path: string, data: Record<strin
 }
 
 // Jump to an adjacent system, preferring one that is still undiscovered. Every jump into an
-// undiscovered system generates 4 fresh neighbours (lib/game/world.ts), so fresh territory is
+// undiscovered system mints a seeded-random 1–4 new systems (at least one always minted —
-// always available — picking the FIRST edge instead ping-pongs between exhausted systems, because
+// lib/game/world.ts #51), so fresh territory is always available — picking the FIRST edge
-// edges come back in insertion order and the oldest route out of a system is usually the one that
+// instead ping-pongs between exhausted systems, because edges come back in insertion order and
-// led here. Falls back to any non-current adjacent system if none is undiscovered. The jump is
+// the oldest route out of a system is usually the one that led here. Falls back to any
-// queued with a default one-person crew and ticked to completion (resolveAction) before this
+// non-current adjacent system if none is undiscovered. The jump is queued with a default
-// returns, so the caller is already standing in the target system, not merely en route to it.
+// one-person crew and ticked to completion (resolveAction) before this returns, so the caller
+// is already standing in the target system, not merely en route to it.
 export async function jumpToFreshSystem(page: Page): Promise<WorldState> {
   const world = (await (await page.request.get('/api/world')).json()) as WorldState;
   const currentId = world.systems.find((s) => s.current)!.id;

e2e/smoke.spec.ts

@@ -199,6 +199,46 @@ test('jumping to an adjacent system updates the world state and turn counter', a
   expect(after.systems.find((s) => s.current)?.id).toBe(targetId);
 });
 
+test('#51: jumping into undiscovered territory mints 1–4 new systems, each routed to the target, and the graph stays connected', async ({ page }) => {
+  await drainQueue(page);
+  const before = (await (await page.request.get('/api/world')).json()) as WorldState;
+
+  const after = await jumpToFreshSystem(page);
+  const target = after.systems.find((s) => s.current)!;
+
+  const beforeIds = new Set(before.systems.map((s) => s.id));
+  const fresh = after.systems.filter((s) => !beforeIds.has(s.id));
+  // #51: seeded-random 1–4 new systems (the frontier guarantee ensures at least one)
+  expect(fresh.length).toBeGreaterThanOrEqual(1);
+  expect(fresh.length).toBeLessThanOrEqual(4);
+  // all new systems are undiscovered
+  expect(fresh.every((s) => !s.discovered)).toBe(true);
+  // each new system is directly routed to the jump target
+  for (const n of fresh) {
+    expect(after.edges.some(([a, b]) => (a === target.id && b === n.id) || (a === n.id && b === target.id))).toBe(true);
+  }
+  // the whole graph stays connected: BFS from the target reaches every system
+  const adj = new Map<number, number[]>();
+  for (const [a, b] of after.edges) {
+    if (!adj.has(a)) adj.set(a, []);
+    if (!adj.has(b)) adj.set(b, []);
+    adj.get(a)!.push(b);
+    adj.get(b)!.push(a);
+  }
+  const seen = new Set([target.id]);
+  const queue = [target.id];
+  while (queue.length > 0) {
+    const cur = queue.shift()!;
+    for (const nb of adj.get(cur) ?? []) {
+      if (!seen.has(nb)) {
+        seen.add(nb);
+        queue.push(nb);
+      }
+    }
+  }
+  expect(seen.size).toBe(after.systems.length); // no orphaned systems
+});
+
 test('local system shows the new current system after a jump, without a page reload (#30)', async ({ page }) => {
   await drainQueue(page); // retry-safety: a failed earlier attempt may have left a row queued (an in-transit JUMP would 409 every new queue)
   const before = (await (await page.request.get('/api/world')).json()) as WorldState;
@@ -1006,3 +1046,47 @@ test('NEXT TURN with an empty queue is a free skip — +1 turn, the strip stays
   expect(after.turn).toBe(T + 1);
   expect(after.tasks.length).toBe(0);
 });
+
+test('NEXT TURN button is full-width in the right pane and not covered by the task strip (#52)', async ({ page }) => {
+  await drainQueue(page);
+  const world = (await (await page.request.get('/api/world')).json()) as WorldStateQ;
+  const currentId = world.systems.find((s) => s.current)!.id;
+  const edge = world.edges.find(([a, b]) => a === currentId || b === currentId)!;
+  const targetId = edge[0] === currentId ? edge[1] : edge[0];
+  const { crew } = (await (await page.request.get('/api/crew')).json()) as { crew: CrewDto[]; tasks: QueueTaskDto[] };
+  expect(crew.length).toBeGreaterThanOrEqual(1);
+
+  // Queue a one-person JUMP and deliberately do not tick it (the #44 jump scenarios' pattern,
+  // the in-transit 409 one leaves it that way on purpose): the strip renders from the shell's
+  // system snapshot — the same queue — so a non-empty queue keeps ACTIVE TASKS visible all test.
+  const res = await page.request.post('/api/jump', { data: { systemId: targetId, leadCrewId: crew[0].id, helperCrewIds: [] } });
+  expect(res.status()).toBe(200);
+  const queued = (await res.json()) as WorldStateQ;
+  expect(queued.tasks.find((t) => t.type === 'JUMP')!.status).toBe('ACTIVE');
+
+  await page.goto('/');
+  await expect(page.getByText('ACTIVE TASKS', { exact: true })).toBeVisible(); // the strip is up
+
+  // Two rects intersect when their x AND y ranges overlap (touching edges do not count).
+  type Box = { x: number; y: number; width: number; height: number };
+  const intersects = (a: Box, b: Box) => a.x < b.x + b.width && b.x < a.x + a.width && a.y < b.y + b.height && b.y < a.y + a.height;
+
+  const buttonBox = await page.getByRole('button', { name: 'NEXT TURN' }).boundingBox();
+  expect(buttonBox).not.toBeNull();
+  // The strip's root div is the parent of its 'ACTIVE TASKS' label (components/task-strip.tsx).
+  const stripBox = await page.getByText('ACTIVE TASKS', { exact: true }).locator('xpath=..').boundingBox();
+  expect(stripBox).not.toBeNull();
+  // The CARGO HOLD panel: the Panel root is the h3 heading's grandparent div (components/ui/panel.tsx).
+  const panelBox = await page.getByRole('heading', { name: 'CARGO HOLD // INVENTORY' }).locator('xpath=ancestor::div[2]').boundingBox();
+  expect(panelBox).not.toBeNull();
+
+  // (a) The button spans the right pane's content width — >= 280 on its own, and within ±8px of
+  // the CARGO HOLD panel, a sibling full-width element in the same pane column.
+  expect(buttonBox!.width).toBeGreaterThanOrEqual(280);
+  expect(Math.abs(buttonBox!.width - panelBox!.width)).toBeLessThanOrEqual(8);
+
+  // (b) The button's box does not intersect the active-tasks strip's box.
+  expect(intersects(buttonBox!, stripBox!)).toBe(false);
+
+  await drainQueue(page); // leave the queue clean for the next scenario
+});

lib/game/save.test.ts

@@ -114,9 +114,10 @@ describe('jumpToSystem success path', () => {
     expect(currentOf(after).id).toBe(target.id)
     expect(after.systems.find((s) => s.id === target.id)!.discovered).toBe(true)
 
-    // Expansion: 4 new undiscovered neighbours around the target, each routed to it.
+    // #51: 1–4 new undiscovered systems minted around the target, each routed to it.
     const fresh = after.systems.filter((s) => !w0.systems.some((p) => p.id === s.id))
-    expect(fresh).toHaveLength(4)
+    expect(fresh.length).toBeGreaterThanOrEqual(1)
+    expect(fresh.length).toBeLessThanOrEqual(4)
     expect(fresh.every((s) => !s.discovered)).toBe(true)
     for (const n of fresh) {
       expect(after.edges.some(([a, b]) => (a === target.id && b === n.id) || (a === n.id && b === target.id))).toBe(true)

lib/game/save.ts

@@ -354,15 +354,33 @@ export async function resolveJumpTask(db: GameDb, task: Task): Promise<void> {
   await db.db.update(schema.solarSystems).set({ isCurrent: true, discovered: true }).where(eq(schema.solarSystems.id, target.id))
 
   if (!target.discovered) {
-    // Growing the chart: a ring of new (undiscovered) neighbours around the newly reached
+    // #51 — growing the chart: a seeded-random 1–4 leg ring around the newly reached
-    // system, so there is always somewhere to jump next and a route back.
+    // system; each leg may attach an existing system (closing a loop) instead of minting.
     const rng = expansionRng(save.seed, save.turn)
     const takenNames = new Set(systems.map((s) => s.name))
-    const ring = generateRing(rng, target.x, target.y, takenNames, systems)
+
+    // Edge keys already touching any pair of this save's systems — an attach must not
+    // duplicate one (the PK on (fromSystem, toSystem) would reject it).
+    const systemIds = new Set(systems.map((s) => s.id))
+    const routes = await db.db.select().from(schema.jumpRoutes)
+    const existingEdgeKeys = new Set(
+      routes
+        .filter((r) => systemIds.has(r.fromSystem) && systemIds.has(r.toSystem))
+        .map((r) => `${Math.min(r.fromSystem, r.toSystem)}-${Math.max(r.fromSystem, r.toSystem)}`),
+    )
+
+    const candidates = systems.filter((s) => s.id !== target.id)
+    const ring = generateRing(rng, target.x, target.y, takenNames, systems, candidates, existingEdgeKeys, target.id)
     const ringIds: number[] = []
     for (const s of ring.systems) ringIds.push(await insertSystemWithBodies(db, save.id, s, save.seed))
     const resolve = (index: number) => (index === 0 ? target.id : ringIds[index - 1])
     await insertRoutes(db, ring.edges, resolve)
+    // Loop-closing attaches: a two-way route from the anchor to each attached candidate.
+    for (const ci of ring.attaches) {
+      const cand = candidates[ci]!
+      await db.db.insert(schema.jumpRoutes).values({ fromSystem: target.id, toSystem: cand.id })
+      await db.db.insert(schema.jumpRoutes).values({ fromSystem: cand.id, toSystem: target.id })
+    }
   }
 
   await db.db.insert(schema.events).values({ saveId: save.id, turn: save.turn, type: 'jump', message: `Jumped to ${target.name}`, createdAt: new Date().toISOString() })

lib/game/world.test.ts

@@ -1,5 +1,6 @@
 import { describe, expect, it } from 'vitest'
-import { bodyRng, explorationRng, generatePlanets, generateRing, generateStartRegion, makeName, mulberry32, reachableWithin, rollExploration } from './world'
+import { ATTACH_PROB, EXPAND_MAX, EXPAND_MIN, bodyRng, explorationRng, generatePlanets, generateRing, generateStartRegion, makeName, mulberry32, reachableWithin, ringEdges, rollExploration } from './world'
+import type { WorldSystem } from './world'
 
 describe('generateStartRegion', () => {
   const region = generateStartRegion(mulberry32(42))
@@ -47,37 +48,133 @@ describe('generateStartRegion', () => {
   })
 })
 
+describe('ringEdges (#51 dedup)', () => {
+  it('n=0 is empty and n=1 is the single anchor↔member edge (the old wheel emitted a [1,1] self-loop here)', () => {
+    expect(ringEdges(0)).toEqual([])
+    expect(ringEdges(1)).toEqual([[0, 1]])
+  })
+
+  it('n=2 is the complete triangle (the old wheel emitted the [1,2] edge twice, as [1,2] and [2,1])', () => {
+    expect(ringEdges(2)).toEqual([[0, 1], [0, 2], [1, 2]])
+  })
+
+  it('n>=3 stays the simple wheel, byte-identical to the legacy output', () => {
+    expect(ringEdges(3)).toEqual([[0, 1], [1, 2], [0, 2], [2, 3], [0, 3], [3, 1]])
+    expect(ringEdges(4)).toEqual([[0, 1], [1, 2], [0, 2], [2, 3], [0, 3], [3, 4], [0, 4], [4, 1]])
+    expect(ringEdges(6)).toEqual([[0, 1], [1, 2], [0, 2], [2, 3], [0, 3], [3, 4], [0, 4], [4, 5], [0, 5], [5, 6], [0, 6], [6, 1]])
+  })
+})
+
 describe('generateRing (expansion)', () => {
-  it('adds four systems spaced away from the anchor and existing positions', () => {
+  // A scripted rng: returns the given values in order, then a constant fallback for the rest
+  // (placeRing's position jitter/radius draws) so a test can pin the leg-drawing phase exactly.
+  function scriptedRng(script: number[], fallback = 0.5): () => number {
+    let i = 0
+    return () => (i < script.length ? script[i++] : fallback)
+  }
+
+  it('#51: mints a seeded-random 1–4 new systems, and all four widths occur across seeds', () => {
+    const counts = new Set<number>()
+    for (let seed = 1; seed <= 200; seed++) {
+      const ring = generateRing(mulberry32(seed), 50, 50, new Set(), [])
+      expect(ring.systems.length).toBeGreaterThanOrEqual(EXPAND_MIN)
+      expect(ring.systems.length).toBeLessThanOrEqual(EXPAND_MAX)
+      counts.add(ring.systems.length)
+    }
+    expect(counts).toEqual(new Set([EXPAND_MIN, EXPAND_MIN + 1, EXPAND_MIN + 2, EXPAND_MAX]))
+  })
+
+  it('with no attach candidates every leg mints, so systems.length is the leg count and attaches is empty', () => {
+    for (let seed = 1; seed <= 50; seed++) {
+      const ring = generateRing(mulberry32(seed), 50, 50, new Set(), [])
+      expect(ring.attaches).toEqual([])
+    }
+  })
+
+  it('mints are spaced away from the anchor and existing positions and never reuse a taken name', () => {
     const takenNames = new Set(['Kepler Drift'])
     const takenPositions = [{ name: 'Kepler Drift', x: 50, y: 50 }]
     const ring = generateRing(mulberry32(7), 50, 50, takenNames, takenPositions)
-
-    expect(ring.systems).toHaveLength(4)
     const ringNames = ring.systems.map((s) => s.name)
     for (const s of ring.systems) {
       expect(Math.hypot(s.x - 50, s.y - 50)).toBeGreaterThanOrEqual(16)
       expect(s.name).not.toBe('Kepler Drift') // never reuses a pre-taken name
     }
-    expect(new Set(ringNames).size).toBe(4) // and makeName claimed them into the set
+    expect(new Set(ringNames).size).toBe(ringNames.length) // and makeName claimed them into the set
     for (const n of ringNames) expect(takenNames.has(n)).toBe(true)
-    expect(ring.edges).toHaveLength(8) // anchor↔each + cycle
+  })
-    for (const [a, b] of ring.edges) {
+
-      expect(a).toBeGreaterThanOrEqual(0)
+  it('edges are exactly the wheel for the mint count, indexing into [anchor, ...systems]', () => {
-      expect(a).toBeLessThan(5)
+    for (let seed = 1; seed <= 50; seed++) {
-      expect(b).toBeGreaterThanOrEqual(0)
+      const ring = generateRing(mulberry32(seed), 50, 50, new Set(), [])
-      expect(b).toBeLessThan(5)
+      const n = ring.systems.length
+      expect(ring.edges).toEqual(ringEdges(n)) // anchor↔each member + the member cycle
+      for (const [a, b] of ring.edges) {
+        expect(a).toBeGreaterThanOrEqual(0)
+        expect(a).toBeLessThan(n + 1)
+        expect(b).toBeGreaterThanOrEqual(0)
+        expect(b).toBeLessThan(n + 1)
+      }
     }
   })
 
-  it('never reuses a taken name', () => {
+  it('attaches existing systems to close loops, but never one already routed to the anchor', () => {
+    const candidates: (WorldSystem & { id: number })[] = [
+      { id: 100, name: 'A', x: 10, y: 10 },
+      { id: 200, name: 'B', x: 20, y: 20 },
+      { id: 300, name: 'C', x: 30, y: 30 },
+    ]
+    // The anchor (id 7) is already routed to candidate 200 — that one can never be attached.
+    const existing = new Set(['7-200'])
+    for (let seed = 1; seed <= 200; seed++) {
+      const ring = generateRing(mulberry32(seed), 50, 50, new Set(), [], candidates, existing, 7)
+      for (const ci of ring.attaches) {
+        expect(ci).toBeGreaterThanOrEqual(0)
+        expect(ci).toBeLessThan(candidates.length)
+        expect(candidates[ci].id).not.toBe(200) // the already-routed candidate is never re-routed
+      }
+      expect(new Set(ring.attaches).size).toBe(ring.attaches.length) // attaches are unique
+      expect(ring.systems.length).toBeGreaterThanOrEqual(EXPAND_MIN) // the frontier still grows
+    }
+  })
+
+  it('frontier guarantee: a scripted all-attach run still mints exactly one system', () => {
+    // Force legCount=4 (first draw 0.8) and all four legs to attach to four DISTINCT candidates
+    // (attach-check 0.1 < ATTACH_PROB, ci draws 0.1/0.3/0.6/0.9 → candidates 0/1/2/3). Without the
+    // guarantee this would mint zero systems and strand the chart; with it, one attach becomes a mint.
+    const candidates: (WorldSystem & { id: number })[] = [
+      { id: 1, name: 'A', x: 10, y: 10 },
+      { id: 2, name: 'B', x: 20, y: 20 },
+      { id: 3, name: 'C', x: 30, y: 30 },
+      { id: 4, name: 'D', x: 40, y: 40 },
+    ]
+    const ring = generateRing(scriptedRng([0.8, 0.1, 0.1, 0.1, 0.3, 0.1, 0.6, 0.1, 0.9]), 50, 50, new Set(), [], candidates, new Set(), 99)
+    expect(ring.systems.length).toBe(1) // one attach converted into a mint
+    expect(ring.attaches).toEqual([0, 1, 2]) // the last-drawn attach (index 3) became the mint
+  })
+
+  it('is deterministic per seed and differs across seeds (candidates + existing edges included)', () => {
+    const candidates: (WorldSystem & { id: number })[] = [
+      { id: 100, name: 'A', x: 10, y: 10 },
+      { id: 200, name: 'B', x: 20, y: 20 },
+    ]
+    const existing = new Set(['7-100'])
+    const positions = [{ name: 'Kepler Drift', x: 50, y: 50 }]
+    const a = generateRing(mulberry32(11), 50, 50, new Set(['Kepler Drift']), positions, candidates, existing, 7)
+    const b = generateRing(mulberry32(11), 50, 50, new Set(['Kepler Drift']), positions, candidates, existing, 7)
+    expect(b).toEqual(a) // same seed + inputs → identical region
+    const c = generateRing(mulberry32(12), 50, 50, new Set(['Kepler Drift']), positions, candidates, existing, 7)
+    expect(JSON.stringify(c)).not.toBe(JSON.stringify(a))
+  })
+
+  it('makeName never reuses a taken name', () => {
     const rng = mulberry32(1)
     const taken = new Set<string>()
     for (let i = 0; i < 40; i++) makeName(rng, taken)
     expect(taken.size).toBe(40)
   })
 
-  it('terminates with numbered variants once all 128 base names are taken', () => {
+  it('makeName terminates with numbered variants once all 128 base names are taken', () => {
     const rng = mulberry32(9)
     const taken = new Set<string>()
     for (let i = 0; i < 128; i++) makeName(rng, taken) // exhaust the whole pool

lib/game/world.ts

@@ -11,7 +11,13 @@ export const START_X = 50
 export const START_Y = 50
 
 const START_RING = 6 // neighbours around the starting system on a new game
-const EXPAND_RING = 4 // new neighbours generated when jumping into an undiscovered system
+// #51 — the spread limit: jumping into an undiscovered system mints a seeded-random number of
+// new systems in [EXPAND_MIN, EXPAND_MAX]. Each "leg" can instead attach an already-known
+// system (closing a loop) with probability ATTACH_PROB, so the chart grows slower and more
+// circular. EXPAND_RING (the old fixed count) is replaced by this range.
+export const EXPAND_MIN = 1
+export const EXPAND_MAX = 4
+export const ATTACH_PROB = 0.35
 const MIN_SPACING = 16 // minimum distance between any two systems in the 0–100 space
 
 // mulberry32 — small fast seeded PRNG; plenty for name/position picking.
@@ -95,7 +101,13 @@ function placeRing(
 // Edges for a ring of n members around an anchor at index 0: anchor↔each member plus the
 // cycle connecting consecutive members (so every system has ≥2 routes and you can always
 // get back). Pairs are indices into [anchor, ...members].
-function ringEdges(n: number): [number, number][] {
+// #51 — small-n special cases: n=0 is empty, n=1 is the single spoke, n=2 is the complete
+// triangle (the old wheel formula produced a self-loop at n=1 and a duplicate edge at n=2).
+// n≥3 is the unchanged wheel.
+export function ringEdges(n: number): [number, number][] {
+  if (n === 0) return []
+  if (n === 1) return [[0, 1]]
+  if (n === 2) return [[0, 1], [0, 2], [1, 2]]
   const edges: [number, number][] = []
   for (let i = 0; i < n; i++) {
     edges.push([0, i + 1])
@@ -121,19 +133,56 @@ export function generateStartRegion(rng: () => number): StartRegion {
 export interface RingRegion {
   systems: WorldSystem[]
   edges: [number, number][] // indices into [anchor, ...systems] — index 0 is the anchor itself
+  attaches: number[] // indices into the attachCandidates array that were attached (loop-closed) rather than minted
 }
 
 // Jumping into an undiscovered system grows the chart: a fresh ring of (undiscovered)
-// neighbours around it. `takenNames`/`takenPositions` are every system already in the save.
+// neighbours around it. #51 — the ring width is a seeded-random 1–4 legs; each leg may
+// instead attach an already-known system (closing a loop) with probability ATTACH_PROB.
+// `takenNames`/`takenPositions` are every system already in the save. `attachCandidates`
+// are the systems eligible for loop-closing (all save systems except the anchor).
+// `existingEdgeKeys` is the set of `${min(a,b)}-${max(a,b)}` keys for routes already
+// touching the anchor, so an attach never duplicates one. `anchorId` is the DB id of the
+// anchor system (used to build edge keys).
 export function generateRing(
   rng: () => number,
   anchorX: number,
   anchorY: number,
   takenNames: Set<string>,
   takenPositions: WorldSystem[],
+  attachCandidates: (WorldSystem & { id: number })[] = [],
+  existingEdgeKeys: Set<string> = new Set(),
+  anchorId: number = 0,
 ): RingRegion {
-  const systems = placeRing(rng, anchorX, anchorY, EXPAND_RING, takenNames, takenPositions)
+  const legCount = EXPAND_MIN + Math.floor(rng() * (EXPAND_MAX - EXPAND_MIN + 1))
-  return { systems, edges: ringEdges(systems.length) }
+
+  let mints = 0
+  const attachSet = new Set<number>()
+  let lastAttachCi = -1
+
+  for (let leg = 0; leg < legCount; leg++) {
+    let isAttach = false
+    if (attachCandidates.length > 0 && rng() < ATTACH_PROB) {
+      const ci = Math.floor(rng() * attachCandidates.length)
+      const a = Math.min(anchorId, attachCandidates[ci]!.id)
+      const b = Math.max(anchorId, attachCandidates[ci]!.id)
+      if (!existingEdgeKeys.has(`${a}-${b}`)) {
+        attachSet.add(ci)
+        lastAttachCi = ci
+        isAttach = true
+      }
+    }
+    if (!isAttach) mints++
+  }
+
+  // Frontier guarantee: at least one new system must be minted so the chart always grows.
+  if (mints === 0 && lastAttachCi >= 0) {
+    attachSet.delete(lastAttachCi)
+    mints = 1
+  }
+
+  const systems = placeRing(rng, anchorX, anchorY, mints, takenNames, takenPositions)
+  return { systems, edges: ringEdges(mints), attaches: [...attachSet] }
 }
 
 // BFS over jump routes: every system within maxHops of fromId, mapped to its shortest hop count.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "space-wanderer",
-  "version": "0.12.0",
+  "version": "0.14.0",
   "private": true,
   "scripts": {
     "dev": "next dev -p 3000",