ui(admin): solid env-colored circle in place of name-hash Avatar

Previous ring approach was too subtle against most env colors. Replace
the DS Avatar with a purpose-built circle rendered in the environment's
chosen color, showing 1–2 letter initials in white. Fills the full
circle so the color reads at a glance from across the list.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cameleer-server-app/src/main/java/com/cameleer/server/app/controller/ApplicationConfigController.java

@@ -24,6 +24,7 @@ import com.cameleer.server.core.storage.DiagramStore;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.Parameter;
 import io.swagger.v3.oas.annotations.responses.ApiResponse;
 import io.swagger.v3.oas.annotations.tags.Tag;
 import jakarta.servlet.http.HttpServletRequest;
@@ -33,6 +34,7 @@ import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.security.core.Authentication;
 import org.springframework.web.bind.annotation.*;
+import org.springframework.web.server.ResponseStatusException;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -114,12 +116,15 @@ public class ApplicationConfigController {
     @ApiResponse(responseCode = "400", description = "Unknown apply value (must be 'staged' or 'live')")
     public ResponseEntity<ConfigUpdateResponse> updateConfig(@EnvPath Environment env,
                                                               @PathVariable String appSlug,
+                                                              @Parameter(name = "apply",
+                                                                      description = "When to apply: 'live' (default) saves and pushes CONFIG_UPDATE to live agents immediately; 'staged' saves without pushing — the next successful deploy applies it.")
                                                               @RequestParam(name = "apply", defaultValue = "live") String apply,
                                                               @RequestBody ApplicationConfig config,
                                                               Authentication auth,
                                                               HttpServletRequest httpRequest) {
         if (!"staged".equalsIgnoreCase(apply) && !"live".equalsIgnoreCase(apply)) {
-            return ResponseEntity.status(HttpStatus.BAD_REQUEST).build();
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST,
+                    "Unknown apply value '" + apply + "' — must be 'staged' or 'live'");
         }
 
         String updatedBy = auth != null ? auth.getName() : "system";

cameleer-server-app/src/main/java/com/cameleer/server/app/runtime/DeploymentExecutor.java

@@ -167,6 +167,21 @@ public class DeploymentExecutor {
                 }
             }
 
+            // === STOP PREVIOUS ACTIVE DEPLOYMENT ===
+            // Container names are deterministic ({tenant}-{env}-{app}-{replica}), so a
+            // previous active deployment holds the Docker names we need. Stop + remove
+            // it before starting new replicas to avoid a 409 name conflict. Excluding
+            // the current deployment id by SQL (not Java) because the newly created
+            // row already has status=STARTING and would otherwise be picked by
+            // findActiveByAppIdAndEnvironmentId ORDER BY created_at DESC LIMIT 1.
+            Optional<Deployment> previous = deploymentRepository.findActiveByAppIdAndEnvironmentIdExcluding(
+                    deployment.appId(), deployment.environmentId(), deployment.id());
+            if (previous.isPresent()) {
+                log.info("Stopping previous deployment {} before starting new replicas", previous.get().id());
+                stopDeploymentContainers(previous.get());
+                deploymentService.markStopped(previous.get().id());
+            }
+
             // === START REPLICAS ===
             updateStage(deployment.id(), DeployStage.START_REPLICAS);
 
@@ -244,16 +259,12 @@ public class DeploymentExecutor {
             pgDeployRepo.updateReplicaStates(deployment.id(), replicaStates);
 
             // === SWAP TRAFFIC ===
+            // Traffic is routed via Traefik Docker labels, so the "swap" happens
+            // implicitly once the new replicas are healthy and the old containers
+            // are gone. The old deployment was already stopped before START_REPLICAS
+            // to free the deterministic container names.
             updateStage(deployment.id(), DeployStage.SWAP_TRAFFIC);
 
-            Optional<Deployment> existing = deploymentRepository.findActiveByAppIdAndEnvironmentId(
-                    deployment.appId(), deployment.environmentId());
-            if (existing.isPresent() && !existing.get().id().equals(deployment.id())) {
-                stopDeploymentContainers(existing.get());
-                deploymentService.markStopped(existing.get().id());
-                log.info("Stopped previous deployment {} for replacement", existing.get().id());
-            }
-
             // === COMPLETE ===
             updateStage(deployment.id(), DeployStage.COMPLETE);
 

cameleer-server-app/src/main/java/com/cameleer/server/app/storage/PostgresDeploymentRepository.java

@@ -63,6 +63,16 @@ public class PostgresDeploymentRepository implements DeploymentRepository {
         return results.isEmpty() ? Optional.empty() : Optional.of(results.get(0));
     }
 
+    @Override
+    public Optional<Deployment> findActiveByAppIdAndEnvironmentIdExcluding(UUID appId, UUID environmentId, UUID excludeDeploymentId) {
+        var results = jdbc.query(
+                "SELECT " + SELECT_COLS + " FROM deployments WHERE app_id = ? AND environment_id = ? " +
+                "AND status IN ('STARTING', 'RUNNING', 'DEGRADED') AND id <> ? " +
+                "ORDER BY created_at DESC LIMIT 1",
+                (rs, rowNum) -> mapRow(rs), appId, environmentId, excludeDeploymentId);
+        return results.isEmpty() ? Optional.empty() : Optional.of(results.get(0));
+    }
+
     public List<Deployment> findByStatus(List<DeploymentStatus> statuses) {
         String placeholders = String.join(",", statuses.stream().map(s -> "'" + s.name() + "'").toList());
         return jdbc.query(
@@ -140,10 +150,12 @@ public class PostgresDeploymentRepository implements DeploymentRepository {
     }
 
     public Optional<Deployment> findLatestSuccessfulByAppAndEnv(UUID appId, UUID envId) {
+        // DEGRADED deploys also carry a snapshot (executor writes before the RUNNING/DEGRADED
+        // split), and represent a config that reached COMPLETE stage — restorable for the user.
         var results = jdbc.query(
                 "SELECT " + SELECT_COLS + " FROM deployments "
                 + "WHERE app_id = ? AND environment_id = ? "
-                + "AND status = 'RUNNING' AND deployed_config_snapshot IS NOT NULL "
+                + "AND status IN ('RUNNING', 'DEGRADED') AND deployed_config_snapshot IS NOT NULL "
                 + "ORDER BY deployed_at DESC NULLS LAST LIMIT 1",
                 (rs, rowNum) -> mapRow(rs), appId, envId);
         return results.isEmpty() ? Optional.empty() : Optional.of(results.get(0));

cameleer-server-app/src/test/java/com/cameleer/server/app/runtime/DeploymentSnapshotIT.java

@@ -20,6 +20,7 @@ import org.springframework.http.HttpEntity;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.MediaType;
+import org.springframework.test.context.TestPropertySource;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
 
@@ -34,8 +35,10 @@ import static org.mockito.Mockito.when;
 
 /**
  * Verifies that DeploymentExecutor writes DeploymentConfigSnapshot on successful
- * RUNNING transition and does NOT write it on a FAILED path.
+ * RUNNING transition and does NOT write it on a FAILED path (both the
+ * startContainer-throws path and the health-check-fails path).
  */
+@TestPropertySource(properties = "cameleer.server.runtime.healthchecktimeout=2")
 class DeploymentSnapshotIT extends AbstractPostgresIT {
 
     @MockBean
@@ -189,6 +192,53 @@ class DeploymentSnapshotIT extends AbstractPostgresIT {
         assertThat(failed.deployedConfigSnapshot()).isNull();
     }
 
+    // -----------------------------------------------------------------------
+    // Test 3: snapshot is NOT populated when the health check never passes.
+    // This exercises the early-exit path in DeploymentExecutor (line ~231) —
+    // startContainer succeeds, but no replica ever reports healthy, so
+    // waitForAnyHealthy returns 0 before the snapshot-write point.
+    // -----------------------------------------------------------------------
+
+    @Test
+    void snapshot_isNotPopulated_whenHealthCheckFails() throws Exception {
+        // --- given: container starts but never becomes healthy ---
+        String fakeContainerId = "fake-unhealthy-" + UUID.randomUUID();
+
+        when(runtimeOrchestrator.isEnabled()).thenReturn(true);
+        when(runtimeOrchestrator.startContainer(any())).thenReturn(fakeContainerId);
+        when(runtimeOrchestrator.getContainerStatus(fakeContainerId))
+                .thenReturn(new ContainerStatus("starting", true, 0, null));
+
+        String appSlug = "snap-unhealthy-" + UUID.randomUUID().toString().substring(0, 8);
+        post("/api/v1/environments/default/apps", String.format("""
+                {"slug": "%s", "displayName": "Snapshot Unhealthy App"}
+                """, appSlug), operatorJwt);
+        put("/api/v1/environments/default/apps/" + appSlug + "/container-config",
+                """
+                {"runtimeType": "spring-boot", "appPort": 8081}
+                """, operatorJwt);
+        String versionId = uploadJar(appSlug, ("fake-jar-unhealthy-" + appSlug).getBytes());
+
+        // --- when: trigger deploy ---
+        JsonNode deployResponse = post(
+                "/api/v1/environments/default/apps/" + appSlug + "/deployments",
+                String.format("{\"appVersionId\": \"%s\"}", versionId), operatorJwt);
+        String deploymentId = deployResponse.path("id").asText();
+
+        // --- await FAILED (healthchecktimeout overridden to 2s in @TestPropertySource) ---
+        await().atMost(30, TimeUnit.SECONDS)
+                .pollInterval(500, TimeUnit.MILLISECONDS)
+                .untilAsserted(() -> {
+                    Deployment d = deploymentRepository.findById(UUID.fromString(deploymentId))
+                            .orElseThrow(() -> new AssertionError("Deployment not found: " + deploymentId));
+                    assertThat(d.status()).isEqualTo(DeploymentStatus.FAILED);
+                });
+
+        // --- then: snapshot is null (snapshot-write is gated behind health check) ---
+        Deployment failed = deploymentRepository.findById(UUID.fromString(deploymentId)).orElseThrow();
+        assertThat(failed.deployedConfigSnapshot()).isNull();
+    }
+
     // -----------------------------------------------------------------------
     // Helpers
     // -----------------------------------------------------------------------

cameleer-server-core/src/main/java/com/cameleer/server/core/runtime/DeploymentRepository.java

@@ -9,6 +9,7 @@ public interface DeploymentRepository {
     List<Deployment> findByEnvironmentId(UUID environmentId);
     Optional<Deployment> findById(UUID id);
     Optional<Deployment> findActiveByAppIdAndEnvironmentId(UUID appId, UUID environmentId);
+    Optional<Deployment> findActiveByAppIdAndEnvironmentIdExcluding(UUID appId, UUID environmentId, UUID excludeDeploymentId);
     UUID create(UUID appId, UUID appVersionId, UUID environmentId, String containerName);
     void updateStatus(UUID id, DeploymentStatus status, String containerId, String errorMessage);
     void markDeployed(UUID id);

ui/src/pages/Admin/EnvironmentsPage.tsx

@@ -1,6 +1,5 @@
 import { useState, useMemo, useEffect } from 'react';
 import {
-  Avatar,
   Badge,
   Button,
   Input,
@@ -221,7 +220,7 @@ export default function EnvironmentsPage() {
               items={filtered}
               renderItem={(env) => (
                 <>
-                  <Avatar name={env.displayName} size="sm" />
+                  <EnvColoredAvatar name={env.displayName} color={env.color} size="sm" />
                   <div className={styles.entityInfo}>
                     <div className={styles.entityName}>{env.displayName}</div>
                     <div className={styles.entityMeta}>
@@ -250,7 +249,7 @@ export default function EnvironmentsPage() {
           selected ? (
             <>
               <div className={styles.detailHeader}>
-                <Avatar name={selected.displayName} size="lg" />
+                <EnvColoredAvatar name={selected.displayName} color={selected.color} size="lg" />
                 <div className={styles.detailHeaderInfo}>
                   <div className={styles.detailName}>
                     {isDefault ? (
@@ -392,6 +391,56 @@ export default function EnvironmentsPage() {
   );
 }
 
+// ── Env-colored Avatar ──────────────────────────────────────────────
+
+// Custom circular initial badge filled with the environment's color. We don't
+// wrap the DS `Avatar` because it picks its background from a name hash with
+// no color override — we need the env color to be the dominant signal.
+const ENV_AVATAR_SIZES = { sm: 24, md: 28, lg: 40 } as const;
+const ENV_AVATAR_FONT = { sm: 10, md: 12, lg: 16 } as const;
+
+function envInitials(displayName: string): string {
+  const words = displayName.trim().split(/\s+/).filter(Boolean);
+  if (words.length === 0) return '?';
+  if (words.length === 1) return words[0].slice(0, 2).toUpperCase();
+  return (words[0][0] + words[1][0]).toUpperCase();
+}
+
+function EnvColoredAvatar({ name, color, size }: {
+  name: string;
+  color: string | null | undefined;
+  size: 'sm' | 'md' | 'lg';
+}) {
+  const dimension = ENV_AVATAR_SIZES[size];
+  const fontSize = ENV_AVATAR_FONT[size];
+  return (
+    <span
+      aria-label={name}
+      title={name}
+      style={{
+        display: 'inline-flex',
+        alignItems: 'center',
+        justifyContent: 'center',
+        width: dimension,
+        height: dimension,
+        borderRadius: '50%',
+        background: envColorVar(color),
+        color: '#fff',
+        fontSize,
+        fontWeight: 600,
+        flexShrink: 0,
+        // subtle border so the circle still reads on bg-surface when the env
+        // color itself is very light (amber, green)
+        border: '1px solid var(--border-subtle)',
+        userSelect: 'none',
+        textShadow: '0 1px 1px rgba(0,0,0,0.25)',
+      }}
+    >
+      {envInitials(name)}
+    </span>
+  );
+}
+
 // ── Default Resource Limits ─────────────────────────────────────────
 
 function DefaultResourcesSection({ environment, onSave, saving }: {

ui/src/pages/AppsTab/AppDeploymentPage/AppDeploymentPage.module.css

@@ -252,6 +252,26 @@
 .statusCardGrid { display: grid; grid-template-columns: 100px 1fr; gap: 6px 12px; font-size: 13px; }
 .statusCardActions { display: flex; gap: 8px; }
 
+.statusCardError {
+  padding: 10px 12px;
+  background: var(--error-bg);
+  border: 1px solid var(--error-border);
+  border-radius: 6px;
+  color: var(--text-primary);
+  font-size: 13px;
+  font-family: var(--font-mono);
+  white-space: pre-wrap;
+  word-break: break-word;
+}
+
+.statusCardErrorLabel {
+  font-family: var(--font-sans);
+  color: var(--error);
+  font-weight: 600;
+  display: block;
+  margin-bottom: 4px;
+}
+
 /* DeploymentTab */
 .deploymentTab {
   display: flex;

ui/src/pages/AppsTab/AppDeploymentPage/Checkpoints.tsx

@@ -15,9 +15,15 @@ export function Checkpoints({ deployments, versions, currentDeploymentId, onRest
   const [open, setOpen] = useState(false);
   const versionMap = new Map(versions.map((v) => [v.id, v]));
 
-  // Only successful deployments (RUNNING with a deployedAt). Exclude the currently-running one.
+  // Deployments that reached COMPLETE stage and captured a snapshot (RUNNING or DEGRADED).
+  // Exclude the currently-running one.
   const checkpoints = deployments
-    .filter((d) => d.deployedAt && d.status === 'RUNNING' && d.id !== currentDeploymentId)
+    .filter(
+      (d) =>
+        d.deployedAt &&
+        (d.status === 'RUNNING' || d.status === 'DEGRADED') &&
+        d.id !== currentDeploymentId,
+    )
     .sort((a, b) => (b.deployedAt ?? '').localeCompare(a.deployedAt ?? ''));
 
   return (

ui/src/pages/AppsTab/AppDeploymentPage/DeploymentTab/DeploymentTab.tsx

@@ -12,11 +12,9 @@ interface Props {
   appSlug: string;
   envSlug: string;
   externalUrl: string;
-  onStop: (deploymentId: string) => void;
-  onStart: (deploymentId: string) => void;
 }
 
-export function DeploymentTab({ deployments, versions, appSlug, envSlug, externalUrl, onStop, onStart }: Props) {
+export function DeploymentTab({ deployments, versions, appSlug, envSlug, externalUrl }: Props) {
   const latest = deployments
     .slice()
     .sort((a, b) => (b.createdAt ?? '').localeCompare(a.createdAt ?? ''))[0] ?? null;
@@ -33,8 +31,6 @@ export function DeploymentTab({ deployments, versions, appSlug, envSlug, externa
         deployment={latest}
         version={version}
         externalUrl={externalUrl}
-        onStop={() => onStop(latest.id)}
-        onStart={() => onStart(latest.id)}
       />
       {latest.status === 'STARTING' && (
         <DeploymentProgress currentStage={latest.deployStage} failed={false} />

ui/src/pages/AppsTab/AppDeploymentPage/DeploymentTab/HistoryDisclosure.tsx

@@ -1,4 +1,4 @@
-import { useState } from 'react';
+import { useEffect, useRef, useState } from 'react';
 import { DataTable } from '@cameleer/design-system';
 import type { Column } from '@cameleer/design-system';
 import type { Deployment, AppVersion } from '../../../../api/queries/admin/apps';
@@ -16,8 +16,15 @@ interface Props {
 export function HistoryDisclosure({ deployments, versions, appSlug, envSlug }: Props) {
   const [open, setOpen] = useState(false);
   const [expanded, setExpanded] = useState<string | null>(null);
+  const logPanelRef = useRef<HTMLDivElement | null>(null);
   const versionMap = new Map(versions.map((v) => [v.id, v]));
 
+  useEffect(() => {
+    if (expanded && logPanelRef.current) {
+      logPanelRef.current.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
+    }
+  }, [expanded]);
+
   const rows = deployments
     .slice()
     .sort((a, b) => (b.createdAt ?? '').localeCompare(a.createdAt ?? ''));
@@ -55,7 +62,11 @@ export function HistoryDisclosure({ deployments, versions, appSlug, envSlug }: P
           {expanded && (() => {
             const d = rows.find((r) => r.id === expanded);
             if (!d) return null;
-            return <StartupLogPanel deployment={d} appSlug={appSlug} envSlug={envSlug} />;
+            return (
+              <div ref={logPanelRef}>
+                <StartupLogPanel deployment={d} appSlug={appSlug} envSlug={envSlug} />
+              </div>
+            );
           })()}
         </>
       )}

ui/src/pages/AppsTab/AppDeploymentPage/DeploymentTab/StatusCard.tsx

@@ -1,4 +1,4 @@
-import { Badge, StatusDot, MonoText, Button } from '@cameleer/design-system';
+import { Badge, StatusDot, MonoText } from '@cameleer/design-system';
 import type { Deployment, AppVersion } from '../../../../api/queries/admin/apps';
 import { timeAgo } from '../../../../utils/format-utils';
 import styles from '../AppDeploymentPage.module.css';
@@ -13,21 +13,13 @@ const DEPLOY_STATUS_DOT = {
   STOPPING: 'stale', STOPPED: 'dead', FAILED: 'error',
 } as const;
 
-function formatBytes(bytes: number): string {
-  if (bytes >= 1_048_576) return `${(bytes / 1_048_576).toFixed(1)} MB`;
-  if (bytes >= 1024) return `${(bytes / 1024).toFixed(1)} KB`;
-  return `${bytes} B`;
-}
-
 interface Props {
   deployment: Deployment;
   version: AppVersion | null;
   externalUrl: string;
-  onStop: () => void;
-  onStart: () => void;
 }
 
-export function StatusCard({ deployment, version, externalUrl, onStop, onStart }: Props) {
+export function StatusCard({ deployment, version, externalUrl }: Props) {
   const running = deployment.replicaStates?.filter((r) => r.status === 'RUNNING').length ?? 0;
   const total = deployment.replicaStates?.length ?? 0;
 
@@ -50,11 +42,12 @@ export function StatusCard({ deployment, version, externalUrl, onStop, onStart }
         <span>Deployed</span><span>{deployment.deployedAt ? timeAgo(deployment.deployedAt) : '—'}</span>
       </div>
 
-      <div className={styles.statusCardActions}>
-        {(deployment.status === 'RUNNING' || deployment.status === 'STARTING' || deployment.status === 'DEGRADED')
-          && <Button size="sm" variant="danger" onClick={onStop}>Stop</Button>}
-        {deployment.status === 'STOPPED' && <Button size="sm" variant="secondary" onClick={onStart}>Start</Button>}
-      </div>
+      {deployment.status === 'FAILED' && deployment.errorMessage && (
+        <div className={styles.statusCardError}>
+          <span className={styles.statusCardErrorLabel}>Failure reason</span>
+          {deployment.errorMessage}
+        </div>
+      )}
     </div>
   );
 }

ui/src/pages/AppsTab/AppDeploymentPage/hooks/useDeploymentPageState.ts

@@ -97,7 +97,7 @@ export function useDeploymentPageState(
         metricsEnabled: agentConfig?.metricsEnabled ?? defaultForm.monitoring.metricsEnabled,
         metricsInterval: defaultForm.monitoring.metricsInterval,
         samplingRate: agentConfig?.samplingRate !== undefined
-          ? (Number.isInteger(agentConfig.samplingRate) ? `${agentConfig.samplingRate}.0` : String(agentConfig.samplingRate))
+          ? String(agentConfig.samplingRate)
           : defaultForm.monitoring.samplingRate,
         compressSuccess: agentConfig?.compressSuccess ?? defaultForm.monitoring.compressSuccess,
         replayEnabled: defaultForm.monitoring.replayEnabled,

ui/src/pages/AppsTab/AppDeploymentPage/hooks/useFormDirty.ts

@@ -1,5 +1,5 @@
 import { useMemo } from 'react';
-import type { DeploymentPageFormState } from './useDeploymentPageState';
+import type { DeploymentPageFormState, MonitoringFormState } from './useDeploymentPageState';
 
 export interface PerTabDirty {
   monitoring: boolean;
@@ -9,13 +9,22 @@ export interface PerTabDirty {
   anyLocalEdit: boolean;
 }
 
+// Normalize free-text numeric fields (user types "1.0" / "1" / "1.00" — all equal).
+// NaN compares as NaN through JSON, which is harmless since both sides coerce the same.
+function normalizeMonitoring(m: MonitoringFormState): Omit<MonitoringFormState, 'samplingRate'> & { samplingRate: number } {
+  const { samplingRate, ...rest } = m;
+  return { ...rest, samplingRate: parseFloat(samplingRate) };
+}
+
 export function useFormDirty(
   form: DeploymentPageFormState,
   serverState: DeploymentPageFormState,
   stagedJar: File | null,
 ): PerTabDirty {
   return useMemo(() => {
-    const monitoring = JSON.stringify(form.monitoring) !== JSON.stringify(serverState.monitoring);
+    const monitoring =
+      JSON.stringify(normalizeMonitoring(form.monitoring)) !==
+      JSON.stringify(normalizeMonitoring(serverState.monitoring));
     const resources = JSON.stringify(form.resources) !== JSON.stringify(serverState.resources);
     const variables = JSON.stringify(form.variables) !== JSON.stringify(serverState.variables);
     const sensitiveKeys = JSON.stringify(form.sensitiveKeys) !== JSON.stringify(serverState.sensitiveKeys);

ui/src/pages/AppsTab/AppDeploymentPage/index.tsx

@@ -1,7 +1,7 @@
 import { useState, useEffect, useRef } from 'react';
 import { useParams, useLocation, useNavigate } from 'react-router';
 import { useQueryClient } from '@tanstack/react-query';
-import { AlertDialog, Button, Tabs, useToast } from '@cameleer/design-system';
+import { AlertDialog, Badge, Button, Tabs, useToast } from '@cameleer/design-system';
 import { useEnvironmentStore } from '../../../api/environment-store';
 import { useEnvironments } from '../../../api/queries/admin/environments';
 import {
@@ -60,9 +60,12 @@ export default function AppDeploymentPage() {
   const { data: deployments = [] } = useDeployments(selectedEnv, app?.slug);
   const currentDeployment = deployments.find((d) => d.status === 'RUNNING') ?? null;
   const activeDeployment = deployments.find((d) => d.status === 'STARTING') ?? null;
+  const latestDeployment = deployments
+    .slice()
+    .sort((a, b) => (b.createdAt ?? '').localeCompare(a.createdAt ?? ''))[0] ?? null;
 
   const { data: agentConfig = null } = useApplicationConfig(app?.slug, selectedEnv);
-  const { data: dirtyState } = useDirtyState(selectedEnv, app?.slug);
+  const { data: dirtyState, isLoading: dirtyLoading } = useDirtyState(selectedEnv, app?.slug);
 
   // Mutations
   const createApp = useCreateApp();
@@ -113,7 +116,11 @@ export default function AppDeploymentPage() {
   const dirty = useFormDirty(form, serverState, stagedJar);
   const { dialogOpen: blockerOpen, confirm: blockerConfirm, cancel: blockerCancel } =
     useUnsavedChangesBlocker(dirty.anyLocalEdit);
-  const serverDirtyAgainstDeploy = dirtyState?.dirty ?? true;
+  // Before the first dirty-state fetch resolves, default to "not dirty" so the
+  // primary button shows `Save (disabled)` — not a stale `Redeploy`. Once loaded,
+  // fall back to `true` if the endpoint failed entirely (fail-safe for the
+  // redeploy path).
+  const serverDirtyAgainstDeploy = app && dirtyLoading ? false : (dirtyState?.dirty ?? true);
   const deploymentInProgress = !!activeDeployment;
   const primaryMode = computeMode({
     deploymentInProgress,
@@ -321,7 +328,14 @@ export default function AppDeploymentPage() {
     const deployment = deployments.find((d) => d.id === deploymentId);
     if (!deployment) return;
     const snap = deployment.deployedConfigSnapshot;
-    if (!snap) return;
+    if (!snap) {
+      toast({
+        title: 'Cannot restore checkpoint',
+        description: 'This checkpoint predates snapshotting and cannot be restored.',
+        variant: 'warning',
+      });
+      return;
+    }
 
     setForm((prev) => {
       const a = snap.agentConfig ?? {};
@@ -387,7 +401,12 @@ export default function AppDeploymentPage() {
     <div className={styles.container}>
       {/* ── Page header ── */}
       <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'space-between', gap: 8 }}>
-        <h2 style={{ margin: 0 }}>{app ? app.displayName : 'Create Application'}</h2>
+        <div style={{ display: 'flex', alignItems: 'center', gap: 10 }}>
+          <h2 style={{ margin: 0 }}>{app ? app.displayName : 'Create Application'}</h2>
+          {app && !deploymentInProgress && (dirty.anyLocalEdit || serverDirtyAgainstDeploy) && (
+            <Badge label="Pending deploy" color="warning" />
+          )}
+        </div>
         <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
           {dirty.anyLocalEdit && (
             <Button
@@ -406,6 +425,40 @@ export default function AppDeploymentPage() {
             enabled={primaryEnabled}
             onClick={primaryMode === 'redeploy' ? handleRedeploy : handleSave}
           />
+          {app && latestDeployment && (
+            latestDeployment.status === 'RUNNING'
+              || latestDeployment.status === 'STARTING'
+              || latestDeployment.status === 'DEGRADED'
+          ) && (
+            <Button size="sm" variant="danger" onClick={() => handleStop(latestDeployment.id)}>
+              Stop
+            </Button>
+          )}
+          {app && latestDeployment && latestDeployment.status === 'STOPPED' && (
+            <Button
+              size="sm"
+              variant="secondary"
+              onClick={() => {
+                setTab('deployment');
+                createDeployment
+                  .mutateAsync({
+                    envSlug: selectedEnv!,
+                    appSlug: app.slug,
+                    appVersionId: latestDeployment.appVersionId,
+                  })
+                  .catch((e: unknown) =>
+                    toast({
+                      title: 'Start failed',
+                      description: e instanceof Error ? e.message : 'Unknown error',
+                      variant: 'error',
+                      duration: 86_400_000,
+                    }),
+                  );
+              }}
+            >
+              Start
+            </Button>
+          )}
           {app && (
             <Button size="sm" variant="danger" onClick={() => setDeleteConfirm(true)}>
               Delete App
@@ -482,26 +535,6 @@ export default function AppDeploymentPage() {
             appSlug={app.slug}
             envSlug={env.slug}
             externalUrl={externalUrl}
-            onStop={handleStop}
-            onStart={(deploymentId) => {
-              // Re-deploy from a specific historical deployment's version
-              const d = deployments.find((dep) => dep.id === deploymentId);
-              if (d && selectedEnv && app) {
-                setTab('deployment');
-                createDeployment.mutateAsync({
-                  envSlug: selectedEnv,
-                  appSlug: app.slug,
-                  appVersionId: d.appVersionId,
-                }).catch((e: unknown) =>
-                  toast({
-                    title: 'Start failed',
-                    description: e instanceof Error ? e.message : 'Unknown error',
-                    variant: 'error',
-                    duration: 86_400_000,
-                  }),
-                );
-              }
-            }}
           />
         )}
         {tab === 'deployment' && !app && (