diff --git a/packages/api/src/.internal-tests/participant-edge.test.ts b/packages/api/src/.internal-tests/participant-edge.test.ts
index 903a3875..8cc7718c 100644
--- a/packages/api/src/.internal-tests/participant-edge.test.ts
+++ b/packages/api/src/.internal-tests/participant-edge.test.ts
@@ -969,6 +969,9 @@ describe("Participant edge cases", () => {
     // includes registrationStatus, and the query has no limit.
     it("hides who was rejected from the public roster", async () => {
       mockFindMany.mockReturnValue([]);
+      mockFindFirst.mockImplementation((table: string) =>
+        table === "hackathons" ? { id: HACK_A, status: "open" } : undefined,
+      );
 
       await callerFor().hackathon.participants({ hackathonId: HACK_A });
 
diff --git a/packages/api/src/.internal-tests/qr-checkin.test.ts b/packages/api/src/.internal-tests/qr-checkin.test.ts
index 26d2dac5..5b502413 100644
--- a/packages/api/src/.internal-tests/qr-checkin.test.ts
+++ b/packages/api/src/.internal-tests/qr-checkin.test.ts
@@ -884,6 +884,9 @@ describe("QR check-in", () => {
             ]
           : [],
       );
+      mockFindFirst.mockImplementation((table: string) =>
+        table === "hackathons" ? { id: HACK_A, status: "open" } : undefined,
+      );
       const anon = appRouter.createCaller(createMockCtx());
 
       const rows: any[] = await anon.hackathon.participants({
diff --git a/packages/api/src/.internal-tests/routers.test.ts b/packages/api/src/.internal-tests/routers.test.ts
index af18dc21..2b7d422d 100644
--- a/packages/api/src/.internal-tests/routers.test.ts
+++ b/packages/api/src/.internal-tests/routers.test.ts
@@ -1024,6 +1024,9 @@ describe("Router Integration and Access Control Verification Suite", () => {
 
     it("should return public participant list for a hackathon", async () => {
       const ctx = createMockCtx();
+      mockFindFirst.mockImplementation((table: string) =>
+        table === "hackathons" ? { id: hackathonId, status: "open" } : undefined,
+      );
       mockFindMany.mockReturnValue([
         {
           hackathonId,
@@ -1040,6 +1043,22 @@ describe("Router Integration and Access Control Verification Suite", () => {
       // event-pass QR payload and is deliberately not returned.
       expect(res[0].user.id).toBe("u1");
     });
+
+    // A draft edition is one nobody outside the team is meant to know exists;
+    // its roster answers like the schedule and gallery do.
+    it("should hide a draft hackathon's participant list", async () => {
+      mockFindFirst.mockImplementation((table: string) =>
+        table === "hackathons" ? { id: hackathonId, status: "draft" } : undefined,
+      );
+      mockFindMany.mockReturnValue([
+        { hackathonId, teamId: null, user: { id: "u1", name: "Ada", image: null }, team: null },
+      ]);
+
+      const caller = appRouter.createCaller(createMockCtx());
+      await expect(caller.hackathon.participants({ hackathonId })).rejects.toThrow(
+        /not found/i,
+      );
+    });
   });
 
   describe("9. Hackathon Creation, Updates and Admin Operations (does it create stuff)", () => {
diff --git a/packages/api/src/middleware/cache.ts b/packages/api/src/middleware/cache.ts
index 1b263dec..295926a7 100644
--- a/packages/api/src/middleware/cache.ts
+++ b/packages/api/src/middleware/cache.ts
@@ -249,6 +249,9 @@ export const clearMembershipCaches = (userId: string) => {
   // `member:me:<userId>`. Evict what is written.
   cache.deletePattern(`member:me:${userId}*`);
   cache.deletePattern(`member:status:${userId}*`);
+  cache.deletePattern(`member:history:${userId}*`);
+  // The staff directory lists every member; `member:*` does not match it.
+  cache.deletePattern("members:list:*");
   invalidatePortalContext(userId);
 };
 
diff --git a/packages/api/src/routers/hackathon/registration.ts b/packages/api/src/routers/hackathon/registration.ts
index 22129278..bdba6835 100644
--- a/packages/api/src/routers/hackathon/registration.ts
+++ b/packages/api/src/routers/hackathon/registration.ts
@@ -9,6 +9,7 @@ import {
 } from "@query/db";
 import { eq, and, sql } from "drizzle-orm";
 import type { DrizzleDB } from "@query/db";
+import { assertHackathonVisible } from "./visibility";
 
 // Postgres unique_violation on unique_participant_per_hackathon — a second
 // submission of the same form. Drizzle wraps every driver error in a
@@ -293,6 +294,10 @@ export const hackathonRegistrationRouter = createTRPCRouter({
   participants: publicProcedure
     .input(z.object({ hackathonId: z.string().uuid("Invalid hackathon ID") }))
     .query(async ({ ctx, input }) => {
+      // Public, so it answers to the same visibility rule as the schedule and
+      // gallery: a draft edition's roster is staff-only.
+      await assertHackathonVisible(ctx, input.hackathonId);
+
       const cacheKey = `hackathon:${input.hackathonId}:participants`;
       const cached = ctx.cache.get<typeof participants>(cacheKey);
       if (cached) return cached;
diff --git a/packages/api/src/routers/judge/admin.ts b/packages/api/src/routers/judge/admin.ts
index 9e13bef2..200d042f 100644
--- a/packages/api/src/routers/judge/admin.ts
+++ b/packages/api/src/routers/judge/admin.ts
@@ -382,6 +382,11 @@ export const judgeAdminRouter = createTRPCRouter({
         })
         .returning();
 
+      // Same as approval: the role gate and the sidebar both cache, so the new
+      // judge would otherwise wait out a 5-minute TTL for the Judge tab.
+      ctx.cache.deletePattern(`${CacheKeys.judge(input.userId)}*`);
+      invalidatePortalContext(input.userId);
+
       return result[0];
     }),
 
@@ -896,9 +901,16 @@ export const judgeAdminRouter = createTRPCRouter({
         });
       }
 
-      await (ctx.db as DrizzleDB)
+      const [removed] = await (ctx.db as DrizzleDB)
         .delete(judges)
-        .where(eq(judges.id, input.judgeId));
+        .where(eq(judges.id, input.judgeId))
+        .returning({ userId: judges.userId });
+
+      // Or the removed judge keeps a Judge tab every procedure behind it refuses.
+      if (removed) {
+        ctx.cache.deletePattern(`${CacheKeys.judge(removed.userId)}*`);
+        invalidatePortalContext(removed.userId);
+      }
       return { success: true };
     }),
 
diff --git a/packages/api/src/routers/team.ts b/packages/api/src/routers/team.ts
index eeec93db..b7f0c76e 100644
--- a/packages/api/src/routers/team.ts
+++ b/packages/api/src/routers/team.ts
@@ -10,6 +10,7 @@ import {
 import { eq, and, or, isNull, inArray, lt, sql } from "drizzle-orm";
 import { VOLATILE_TTL } from "../middleware/cache";
 import type { DrizzleDB } from "@query/db";
+import { assertHackathonVisible } from "./hackathon/visibility";
 
 type Tx = Parameters<Parameters<DrizzleDB["transaction"]>[0]>[0];
 
@@ -980,6 +981,8 @@ export const teamRouter = createTRPCRouter({
   list: protectedProcedure
     .input(z.object({ hackathonId: z.string().uuid("Invalid hackathon ID") }))
     .query(async ({ ctx, input }) => {
+      await assertHackathonVisible(ctx, input.hackathonId);
+
       const cacheKey = `hackathon:${input.hackathonId}:teams`;
 
       const fetchTeams = () =>
diff --git a/sites/mainweb/app/(portal)/api/resume-book/route.ts b/sites/mainweb/app/(portal)/api/resume-book/route.ts
index cf22ce5e..c43ca7da 100644
--- a/sites/mainweb/app/(portal)/api/resume-book/route.ts
+++ b/sites/mainweb/app/(portal)/api/resume-book/route.ts
@@ -26,7 +26,11 @@ export const dynamic = "force-dynamic";
 const PREFETCH = 8;
 
 const csvCell = (value: unknown) => {
-  const text = value == null ? "" : String(value);
+  let text = value == null ? "" : String(value);
+  // Names, schools and majors are member-typed. A leading = + - @ (or tab/CR)
+  // makes Excel and Sheets evaluate the cell as a formula when staff open the
+  // index; a leading apostrophe keeps it text.
+  if (/^[=+\-@\t\r]/.test(text)) text = `'${text}`;
   return /[",\r\n]/.test(text) ? `"${text.replace(/"/g, '""')}"` : text;
 };