diff --git a/package.json b/package.json
index 2489d825..b80b273b 100644
--- a/package.json
+++ b/package.json
@@ -11,7 +11,10 @@
     "skillsInstallation": false,
     "workspaceScheduling": false,
     "remoteSsh": false,
-    "linearIntegration": false
+    "linearIntegration": false,
+    "logs": false,
+    "checks": false,
+    "browser": false
   },
   "env": {
     "dev": {
diff --git a/src-tauri/src/commands/checks.rs b/src-tauri/src/commands/checks.rs
index f666cee9..83921276 100644
--- a/src-tauri/src/commands/checks.rs
+++ b/src-tauri/src/commands/checks.rs
@@ -1,5 +1,7 @@
 use crate::core::checks_logs::{LogBucket, LogQuery, LogRecordView, SqlResult};
 use crate::core::{JobResult, RunSummary, SetupScriptStatus, WorkflowInfo};
+use crate::AppState;
+use tauri::State;
 
 #[tauri::command]
 pub async fn list_workflows(repo_path: String) -> Result<Vec<WorkflowInfo>, String> {
@@ -10,12 +12,17 @@ pub async fn list_workflows(repo_path: String) -> Result<Vec<WorkflowInfo>, Stri
 
 #[tauri::command]
 pub async fn run_workflow_job(
+  state: State<'_, AppState>,
   repo_path: String,
   filename: String,
   job_id: String,
   workspace_id: i64,
   workspace_path: String,
 ) -> Result<JobResult, String> {
+  crate::commands::feature_preview::require(
+    &state,
+    crate::core::feature_preview::PreviewFeature::Checks,
+  )?;
   tauri::async_runtime::spawn_blocking(move || {
     crate::core::run_workflow_job_sync(
       &repo_path,
@@ -31,11 +38,16 @@ pub async fn run_workflow_job(
 
 #[tauri::command]
 pub async fn run_workflow(
+  state: State<'_, AppState>,
   repo_path: String,
   filename: String,
   workspace_id: i64,
   workspace_path: String,
 ) -> Result<Vec<JobResult>, String> {
+  crate::commands::feature_preview::require(
+    &state,
+    crate::core::feature_preview::PreviewFeature::Checks,
+  )?;
   tauri::async_runtime::spawn_blocking(move || {
     crate::core::run_workflow_sync(&repo_path, &filename, workspace_id, &workspace_path)
   })
diff --git a/src-tauri/src/core/feature_preview.rs b/src-tauri/src/core/feature_preview.rs
index a7ecfcd7..78582a18 100644
--- a/src-tauri/src/core/feature_preview.rs
+++ b/src-tauri/src/core/feature_preview.rs
@@ -11,6 +11,9 @@ pub enum PreviewFeature {
   WorkspaceScheduling,
   RemoteSsh,
   LinearIntegration,
+  Logs,
+  Checks,
+  Browser,
 }
 
 impl PreviewFeature {
@@ -20,6 +23,9 @@ impl PreviewFeature {
       Self::WorkspaceScheduling => "workspaceScheduling",
       Self::RemoteSsh => "remoteSsh",
       Self::LinearIntegration => "linearIntegration",
+      Self::Logs => "logs",
+      Self::Checks => "checks",
+      Self::Browser => "browser",
     }
   }
 
@@ -98,6 +104,9 @@ mod tests {
     assert!(!package_json_default(PreviewFeature::WorkspaceScheduling));
     assert!(!package_json_default(PreviewFeature::RemoteSsh));
     assert!(!package_json_default(PreviewFeature::LinearIntegration));
+    assert!(!package_json_default(PreviewFeature::Logs));
+    assert!(!package_json_default(PreviewFeature::Checks));
+    assert!(!package_json_default(PreviewFeature::Browser));
   }
 
   #[test]
diff --git a/src/components/LogsTimeseriesChart.tsx b/src/components/LogsTimeseriesChart.tsx
index 12f13e4f..ca3bb01c 100644
--- a/src/components/LogsTimeseriesChart.tsx
+++ b/src/components/LogsTimeseriesChart.tsx
@@ -62,7 +62,7 @@ export function LogsTimeseriesChart({
     const index = new Map(timeline.map((t, i) => [t, i]));
 
     const series = SERIES.map(({ severity, label, color }) => {
-      const data = new Array<number>(timeline.length).fill(0);
+      const data = Array.from<number>({ length: timeline.length }).fill(0);
       for (const bucket of buckets) {
         if (bucket.severity_text !== severity) continue;
         const at = index.get(Date.parse(bucket.bucket));
diff --git a/src/components/ShowWorkspace.tsx b/src/components/ShowWorkspace.tsx
index 3a172d87..6adf0232 100644
--- a/src/components/ShowWorkspace.tsx
+++ b/src/components/ShowWorkspace.tsx
@@ -240,6 +240,9 @@ export const ShowWorkspace = ({
   const { addToast } = useToast();
   const workspaceScheduling = usePreviewFeature("workspaceScheduling");
   const linearIntegration = usePreviewFeature("linearIntegration");
+  const logsEnabled = usePreviewFeature("logs");
+  const checksEnabled = usePreviewFeature("checks");
+  const browserEnabled = usePreviewFeature("browser");
   const { fontSize } = useTerminalSettingsStore();
 
   const { data: remoteInfo } = useGitRemoteInfo(effectiveRepoPath || undefined);
@@ -326,6 +329,21 @@ export const ShowWorkspace = ({
   const [scrollToCommitId, setScrollToCommitId] = useState<string | null>(null);
   const [showFileBrowserInCode, setShowFileBrowserInCode] = useState(false);
 
+  useEffect(() => {
+    if (
+      (!logsEnabled && activeTab === "logs") ||
+      (!checksEnabled && activeTab === "checks")
+    ) {
+      setActiveTab("overview");
+    }
+  }, [activeTab, checksEnabled, logsEnabled]);
+
+  useEffect(() => {
+    if (!browserEnabled && reviewSubView === "browser") {
+      setReviewSubView("diff");
+    }
+  }, [browserEnabled, reviewSubView]);
+
   // `treq send --browser <url-or-file>` opens the Browser view directly,
   // instead of showing an attachment preview like image/text sends do.
   const treqSendAssets = useTreqSendStore((s) => s.assets);
@@ -1294,14 +1312,16 @@ export const ShowWorkspace = ({
                   </span>
                 )}
               </TabsTrigger>
-              <TabsTrigger
-                value="checks"
-                className="inline-flex items-center gap-1.5"
-              >
-                <Workflow className="w-4 h-4" />
-                <span>Checks</span>
-              </TabsTrigger>
-              {!workspace && (
+              {checksEnabled && (
+                <TabsTrigger
+                  value="checks"
+                  className="inline-flex items-center gap-1.5"
+                >
+                  <Workflow className="w-4 h-4" />
+                  <span>Checks</span>
+                </TabsTrigger>
+              )}
+              {!workspace && logsEnabled && (
                 <TabsTrigger
                   value="logs"
                   className="inline-flex items-center gap-1.5"
@@ -1312,7 +1332,7 @@ export const ShowWorkspace = ({
               )}
             </TabsList>
           </Tabs>
-          {activeTab === "changes" && (
+          {activeTab === "changes" && browserEnabled && (
             <DropdownMenu>
               <DropdownMenuTrigger asChild>
                 <Button
diff --git a/src/lib/features.test.ts b/src/lib/features.test.ts
index 5999a08c..f5b51d02 100644
--- a/src/lib/features.test.ts
+++ b/src/lib/features.test.ts
@@ -8,12 +8,15 @@ import {
 } from "./features";
 
 describe("preview features", () => {
-  it("lists the four preview features with docs paths", () => {
+  it("lists all preview features with docs paths", () => {
     expect(PREVIEW_FEATURES.map((feature) => feature.id)).toEqual([
       "skillsInstallation",
       "workspaceScheduling",
       "remoteSsh",
       "linearIntegration",
+      "logs",
+      "checks",
+      "browser",
     ]);
     for (const feature of PREVIEW_FEATURES) {
       expect(feature.docsPath.startsWith("/docs/")).toBe(true);
@@ -26,6 +29,9 @@ describe("preview features", () => {
     expect(FEATURES.workspaceScheduling).toBe(false);
     expect(FEATURES.remoteSsh).toBe(false);
     expect(FEATURES.linearIntegration).toBe(false);
+    expect(FEATURES.logs).toBe(false);
+    expect(FEATURES.checks).toBe(false);
+    expect(FEATURES.browser).toBe(false);
   });
 
   it("defaults every preview flag on in test and dev", () => {
@@ -33,6 +39,9 @@ describe("preview features", () => {
     expect(previewFeatureDefault("workspaceScheduling")).toBe(true);
     expect(previewFeatureDefault("remoteSsh")).toBe(true);
     expect(previewFeatureDefault("linearIntegration")).toBe(true);
+    expect(previewFeatureDefault("logs")).toBe(true);
+    expect(previewFeatureDefault("checks")).toBe(true);
+    expect(previewFeatureDefault("browser")).toBe(true);
   });
 
   it("honors stored true/false over the startup default", () => {
diff --git a/src/lib/features.ts b/src/lib/features.ts
index 3cdc0dba..a925bfc0 100644
--- a/src/lib/features.ts
+++ b/src/lib/features.ts
@@ -7,6 +7,9 @@ export const PREVIEW_FEATURE_IDS = [
   "workspaceScheduling",
   "remoteSsh",
   "linearIntegration",
+  "logs",
+  "checks",
+  "browser",
 ] as const;
 
 export type PreviewFeatureId = (typeof PREVIEW_FEATURE_IDS)[number];
@@ -38,6 +41,21 @@ export const PREVIEW_FEATURES: readonly PreviewFeature[] = [
     title: "Linear integration",
     docsPath: "/docs/concepts/linear-integration",
   },
+  {
+    id: "logs",
+    title: "Logs",
+    docsPath: "/docs/concepts/logs",
+  },
+  {
+    id: "checks",
+    title: "Checks",
+    docsPath: "/docs/concepts/checks",
+  },
+  {
+    id: "browser",
+    title: "Browser",
+    docsPath: "/docs/concepts/browser",
+  },
 ];
 
 export function previewSettingKey(id: PreviewFeatureId): string {
diff --git a/src/stores/featurePreviewStore.ts b/src/stores/featurePreviewStore.ts
index 40607c20..e794f1f1 100644
--- a/src/stores/featurePreviewStore.ts
+++ b/src/stores/featurePreviewStore.ts
@@ -23,6 +23,9 @@ function defaultFlags(): PreviewFlags {
     workspaceScheduling: previewFeatureDefault("workspaceScheduling"),
     remoteSsh: previewFeatureDefault("remoteSsh"),
     linearIntegration: previewFeatureDefault("linearIntegration"),
+    logs: previewFeatureDefault("logs"),
+    checks: previewFeatureDefault("checks"),
+    browser: previewFeatureDefault("browser"),
   };
 }
 
diff --git a/test/integration/feature-preview.test.tsx b/test/integration/feature-preview.test.tsx
index 01c49c10..2d36a8cb 100644
--- a/test/integration/feature-preview.test.tsx
+++ b/test/integration/feature-preview.test.tsx
@@ -1,10 +1,21 @@
 import * as React from "react";
 import { beforeEach, describe, expect, it } from "vitest";
-import { createTestRepo, openRepo } from "../utils";
+import {
+  createTestRepo,
+  findSidebarBranchElement,
+  openRepo,
+  writeRepoFile,
+} from "../utils";
 import { render, screen } from "../test-utils";
 import { Dashboard } from "../../src/components/Dashboard";
 import userEvent from "@testing-library/user-event";
-import { createWorkspace, scheduleWorkspaces } from "../../src/lib/api";
+import {
+  createWorkspace,
+  runWorkflow,
+  scheduleWorkspaces,
+  setSetting,
+  trustRepo,
+} from "../../src/lib/api";
 import { previewSettingKey } from "../../src/lib/features";
 
 describe("feature preview settings", () => {
@@ -35,6 +46,27 @@ describe("feature preview settings", () => {
       screen.getByRole("button", { name: "Workspace scheduling" }),
     ).toBeTruthy();
     expect(screen.getByRole("button", { name: "Remote SSH" })).toBeTruthy();
+    expect(screen.getByRole("button", { name: "Logs" })).toBeTruthy();
+    expect(screen.getByRole("button", { name: "Checks" })).toBeTruthy();
+    expect(screen.getByRole("button", { name: "Browser" })).toBeTruthy();
+  });
+
+  it("hides Logs, Checks, and the Diff/Browser switcher when disabled", async () => {
+    await createWorkspace(repoPath, "feat/hidden-previews");
+    await openFeaturePreview();
+    await user.click(screen.getByLabelText("Logs"));
+    await user.click(screen.getByLabelText("Checks"));
+    await user.click(screen.getByLabelText("Browser"));
+    await user.click(screen.getByRole("button", { name: "Close" }));
+
+    expect(screen.queryByRole("tab", { name: /^Logs/ })).toBeNull();
+    expect(screen.queryByRole("tab", { name: /^Checks/ })).toBeNull();
+
+    await user.click(await findSidebarBranchElement("feat/hidden-previews"));
+    await user.click(await screen.findByRole("tab", { name: "Changes" }));
+    expect(
+      screen.queryByRole("button", { name: "Switch review view" }),
+    ).toBeNull();
   });
 
   it("hides the Skills tab when skills installation is off", async () => {
@@ -89,4 +121,20 @@ describe("feature preview rust gates", () => {
       scheduleWorkspaces(repoPath, [workspaceId], "2099-01-01T00:00:00Z"),
     ).rejects.toThrow(/workspaceScheduling/);
   });
+
+  it("rejects workflow checks when the preview flag is off", async () => {
+    const { repoPath } = createTestRepo(false);
+    const workspaceId = await createWorkspace(repoPath, "feat/checks-gated");
+    await writeRepoFile(
+      repoPath,
+      ".treq/workflows/ci.yaml",
+      "name: CI\non: workflow_dispatch\njobs:\n  test:\n    steps:\n      - run: echo test\n",
+    );
+    await trustRepo(repoPath);
+    await setSetting(previewSettingKey("checks"), "false");
+
+    await expect(
+      runWorkflow(repoPath, "ci.yaml", workspaceId, repoPath),
+    ).rejects.toThrow(/checks/);
+  });
 });