diff --git a/frontend/src/screens/engagements/EngagementCreateDialog.tsx b/frontend/src/screens/engagements/EngagementCreateDialog.tsx
new file mode 100644
index 0000000..3a0581b
--- /dev/null
+++ b/frontend/src/screens/engagements/EngagementCreateDialog.tsx
@@ -0,0 +1,447 @@
+import {
+  useEffect,
+  useId,
+  useMemo,
+  useRef,
+  useState,
+  type FormEvent,
+  type KeyboardEvent,
+  type ReactNode,
+  type Ref,
+} from 'react';
+import { useMutation, useQueryClient } from '@tanstack/react-query';
+import { Button } from '@/components/ui/Button';
+import { ApiClientError } from '@/lib/api';
+import type { ApiValidationError } from '@/types/api';
+import { createEngagement, ENGAGEMENTS_QUERY_KEY } from './engagementsApi';
+
+interface EngagementCreateDialogProps {
+  onClose: () => void;
+}
+
+type FieldErrors = Partial<Record<'name' | 'client_name' | 'description', string>>;
+
+/**
+ * "Arm engagement" dialog.
+ *
+ * Visual grammar:
+ *   - Backdrop: graphite dim + faint scanline texture, no blur. Reads as
+ *     "the cockpit is paused while you issue a command", not a sleek
+ *     SaaS overlay.
+ *   - Surface: --surface-3 (one level above panels), corner-mark utility
+ *     at the four corners, hairline divider beneath the masthead.
+ *   - Inputs: label-system uppercase + underline that lights amber on
+ *     focus. No rounded boxes; the form should read as a console.
+ *   - Submit: primary amber Button — the same accent used for RT-only
+ *     actions throughout the app, so the action lineage is obvious.
+ *
+ * Behavior:
+ *   - Esc and outside click close (unless the mutation is in flight).
+ *   - Backend 422 Pydantic errors are mapped to per-field inline messages.
+ *   - Other 4xx/5xx surface as a generic top-of-form alert.
+ */
+export function EngagementCreateDialog({ onClose }: EngagementCreateDialogProps) {
+  const titleId = useId();
+  const surfaceRef = useRef<HTMLDivElement>(null);
+  const firstFieldRef = useRef<HTMLInputElement>(null);
+
+  const [name, setName] = useState('');
+  const [clientName, setClientName] = useState('');
+  const [description, setDescription] = useState('');
+  const [fieldErrors, setFieldErrors] = useState<FieldErrors>({});
+  const [topError, setTopError] = useState<string | null>(null);
+
+  const queryClient = useQueryClient();
+
+  const mutation = useMutation({
+    mutationFn: createEngagement,
+    onSuccess: async () => {
+      await queryClient.invalidateQueries({ queryKey: ENGAGEMENTS_QUERY_KEY });
+      onClose();
+    },
+    onError: (err) => {
+      if (err instanceof ApiClientError && err.status === 422 && err.body) {
+        setFieldErrors(mapValidationErrors(err.body as ApiValidationError));
+        setTopError(null);
+        return;
+      }
+      if (err instanceof ApiClientError && err.status === 401) {
+        setTopError('Session expirée. Reconnectez-vous.');
+        return;
+      }
+      setTopError('Création impossible. Réessayez dans un instant.');
+    },
+  });
+
+  const isPending = mutation.isPending;
+
+  // Focus the first field on open. ESC closes unless a request is in flight.
+  useEffect(() => {
+    firstFieldRef.current?.focus();
+    const onKeyDown = (e: globalThis.KeyboardEvent) => {
+      if (e.key === 'Escape' && !isPending) {
+        e.preventDefault();
+        onClose();
+      }
+    };
+    window.addEventListener('keydown', onKeyDown);
+    return () => window.removeEventListener('keydown', onKeyDown);
+  }, [isPending, onClose]);
+
+  // Rudimentary focus trap: cycle Tab/Shift+Tab within the dialog.
+  const handleSurfaceKeyDown = (e: KeyboardEvent<HTMLDivElement>) => {
+    if (e.key !== 'Tab' || !surfaceRef.current) return;
+    const focusables = surfaceRef.current.querySelectorAll<HTMLElement>(
+      'input, textarea, button, [tabindex]:not([tabindex="-1"])',
+    );
+    if (focusables.length === 0) return;
+    const first = focusables[0];
+    const last = focusables[focusables.length - 1];
+    if (!first || !last) return;
+    const active = document.activeElement;
+    if (e.shiftKey && active === first) {
+      e.preventDefault();
+      last.focus();
+    } else if (!e.shiftKey && active === last) {
+      e.preventDefault();
+      first.focus();
+    }
+  };
+
+  const handleSubmit = (e: FormEvent) => {
+    e.preventDefault();
+    setFieldErrors({});
+    setTopError(null);
+    if (!name.trim()) {
+      setFieldErrors({ name: 'Nom requis.' });
+      return;
+    }
+    mutation.mutate({
+      name: name.trim(),
+      client_name: clientName.trim() || undefined,
+      description: description.trim() || undefined,
+    });
+  };
+
+  const draftId = useMemo(() => generateDraftId(), []);
+
+  return (
+    <div
+      role="presentation"
+      onMouseDown={(e) => {
+        if (e.target === e.currentTarget && !isPending) onClose();
+      }}
+      style={{
+        position: 'fixed',
+        inset: 0,
+        zIndex: 50,
+        background:
+          'radial-gradient(circle at 50% 35%, oklch(7.4% 0.012 247 / 0.55), oklch(5.8% 0.012 247 / 0.82) 60%)',
+        backgroundColor: 'oklch(5.8% 0.012 247 / 0.78)',
+      }}
+    >
+      {/* Faint scanline texture overlay — reads as "instrument feed paused" */}
+      <div
+        aria-hidden="true"
+        style={{
+          position: 'absolute',
+          inset: 0,
+          backgroundImage:
+            'repeating-linear-gradient(0deg, transparent 0, transparent 2px, oklch(100% 0 0 / 0.012) 2px, oklch(100% 0 0 / 0.012) 3px)',
+          pointerEvents: 'none',
+        }}
+      />
+
+      <div
+        role="dialog"
+        aria-modal="true"
+        aria-labelledby={titleId}
+        ref={surfaceRef}
+        onKeyDown={handleSurfaceKeyDown}
+        className="corner-mark"
+        style={{
+          position: 'absolute',
+          top: '14%',
+          left: '50%',
+          transform: 'translateX(-50%)',
+          width: 'min(520px, calc(100vw - 32px))',
+          backgroundColor: 'var(--surface-3)',
+          border: '1px solid var(--line-strong)',
+          borderRadius: 'var(--radius-md)',
+          boxShadow: 'var(--shadow-pop)',
+          animation: 'dialog-in 140ms var(--ease-mech) both',
+        }}
+      >
+        {/* Masthead */}
+        <div
+          className="flex items-center justify-between gap-3 px-5 py-3 border-b"
+          style={{ borderColor: 'var(--line-default)' }}
+        >
+          <div className="flex items-center gap-3">
+            <span
+              aria-hidden="true"
+              className="status-dot pulsing"
+              style={{ color: 'var(--accent-rt)' }}
+            />
+            <h2
+              id={titleId}
+              className="label-system"
+              style={{ color: 'var(--accent-rt)', letterSpacing: '0.18em' }}
+            >
+              ARM · NEW ENGAGEMENT
+            </h2>
+          </div>
+          <span
+            className="font-mono tabular text-fg-faint"
+            style={{ fontSize: '10.5px' }}
+          >
+            {draftId}
+          </span>
+        </div>
+
+        {/* Amber hairline accent */}
+        <div
+          aria-hidden="true"
+          style={{
+            height: 1,
+            background:
+              'linear-gradient(90deg, transparent 0%, var(--accent-rt) 50%, transparent 100%)',
+            opacity: 0.55,
+          }}
+        />
+
+        <form onSubmit={handleSubmit} className="px-5 py-4 space-y-4" noValidate>
+          {topError && (
+            <div
+              role="alert"
+              className="label-system"
+              style={{
+                color: 'var(--state-failed)',
+                border: '1px solid var(--state-failed)',
+                padding: '6px 10px',
+                borderRadius: 'var(--radius-sm)',
+              }}
+            >
+              {topError}
+            </div>
+          )}
+
+          <ConsoleField
+            label="Engagement name"
+            required
+            value={name}
+            onChange={setName}
+            error={fieldErrors.name}
+            disabled={isPending}
+            placeholder="OPERATION RUSTED ANCHOR"
+            ref={firstFieldRef}
+            mono
+          />
+          <ConsoleField
+            label="Client"
+            value={clientName}
+            onChange={setClientName}
+            error={fieldErrors.client_name}
+            disabled={isPending}
+            placeholder="Démo Client X"
+          />
+          <ConsoleTextarea
+            label="Brief"
+            value={description}
+            onChange={setDescription}
+            error={fieldErrors.description}
+            disabled={isPending}
+            placeholder="Scope notes, ROE pointers, post-mission expectations."
+          />
+
+          <div
+            className="flex items-center justify-between gap-3 pt-3 border-t"
+            style={{ borderColor: 'var(--line-default)' }}
+          >
+            <span className="label-system text-fg-faint">
+              {isPending ? '// transmitting …' : '// awaiting confirmation'}
+            </span>
+            <div className="flex items-center gap-2">
+              <Button
+                type="button"
+                variant="ghost"
+                size="sm"
+                onClick={onClose}
+                disabled={isPending}
+              >
+                Cancel
+              </Button>
+              <Button type="submit" variant="primary" size="sm" disabled={isPending}>
+                {isPending ? 'Arming …' : 'Arm engagement →'}
+              </Button>
+            </div>
+          </div>
+        </form>
+      </div>
+
+      {/* keyframes inlined so the component is self-contained */}
+      <style>{`
+        @keyframes dialog-in {
+          0%   { opacity: 0; transform: translate(-50%, calc(-50% + 4px)) translateY(8px); }
+          100% { opacity: 1; transform: translateX(-50%) translateY(0); }
+        }
+      `}</style>
+    </div>
+  );
+}
+
+function mapValidationErrors(body: ApiValidationError): FieldErrors {
+  const out: FieldErrors = {};
+  for (const item of body.detail) {
+    const last = item.loc[item.loc.length - 1];
+    if (last === 'name' || last === 'client_name' || last === 'description') {
+      out[last] = item.msg;
+    }
+  }
+  return out;
+}
+
+function generateDraftId(): string {
+  const t = new Date();
+  const pad = (n: number) => String(n).padStart(2, '0');
+  return `DRAFT-${t.getUTCFullYear().toString().slice(-2)}${pad(t.getUTCMonth() + 1)}${pad(t.getUTCDate())}-${pad(t.getUTCHours())}${pad(t.getUTCMinutes())}`;
+}
+
+interface ConsoleFieldProps {
+  label: string;
+  value: string;
+  onChange: (next: string) => void;
+  required?: boolean;
+  disabled?: boolean;
+  placeholder?: string;
+  error?: string;
+  mono?: boolean;
+}
+
+function ConsoleField({
+  label,
+  value,
+  onChange,
+  required,
+  disabled,
+  placeholder,
+  error,
+  mono,
+  ref,
+}: ConsoleFieldProps & { ref?: Ref<HTMLInputElement> }): ReactNode {
+  const id = useId();
+  return (
+    <div className="space-y-1.5">
+      <label htmlFor={id} className="block label-system flex items-center justify-between">
+        <span>{label}</span>
+        {required && (
+          <span style={{ color: 'var(--accent-rt)' }} aria-hidden="true">
+            · required
+          </span>
+        )}
+      </label>
+      <input
+        id={id}
+        ref={ref}
+        type="text"
+        value={value}
+        onChange={(e) => onChange(e.target.value)}
+        disabled={disabled}
+        placeholder={placeholder}
+        aria-invalid={error ? 'true' : undefined}
+        aria-describedby={error ? `${id}-err` : undefined}
+        className={mono ? 'font-mono tabular' : 'font-sans'}
+        style={{
+          width: '100%',
+          height: 30,
+          padding: '0 0 4px 0',
+          backgroundColor: 'transparent',
+          color: 'var(--fg-default)',
+          border: 'none',
+          borderBottom: `1px solid ${error ? 'var(--state-failed)' : 'var(--line-strong)'}`,
+          borderRadius: 0,
+          fontSize: 13,
+          outline: 'none',
+        }}
+        onFocus={(e) => {
+          if (!error) {
+            e.currentTarget.style.borderBottomColor = 'var(--accent-rt)';
+          }
+        }}
+        onBlur={(e) => {
+          if (!error) {
+            e.currentTarget.style.borderBottomColor = 'var(--line-strong)';
+          }
+        }}
+      />
+      {error && (
+        <p
+          id={`${id}-err`}
+          className="label-system"
+          style={{ color: 'var(--state-failed)' }}
+        >
+          {error}
+        </p>
+      )}
+    </div>
+  );
+}
+
+interface ConsoleTextareaProps {
+  label: string;
+  value: string;
+  onChange: (next: string) => void;
+  disabled?: boolean;
+  placeholder?: string;
+  error?: string;
+}
+
+function ConsoleTextarea({
+  label,
+  value,
+  onChange,
+  disabled,
+  placeholder,
+  error,
+}: ConsoleTextareaProps): ReactNode {
+  const id = useId();
+  return (
+    <div className="space-y-1.5">
+      <label htmlFor={id} className="block label-system">
+        {label}
+      </label>
+      <textarea
+        id={id}
+        value={value}
+        onChange={(e) => onChange(e.target.value)}
+        disabled={disabled}
+        placeholder={placeholder}
+        rows={4}
+        aria-invalid={error ? 'true' : undefined}
+        aria-describedby={error ? `${id}-err` : undefined}
+        className="font-sans"
+        style={{
+          width: '100%',
+          padding: '8px 10px',
+          backgroundColor: 'var(--surface-inset)',
+          color: 'var(--fg-default)',
+          border: `1px solid ${error ? 'var(--state-failed)' : 'var(--line-default)'}`,
+          borderRadius: 'var(--radius-sm)',
+          fontSize: 12.5,
+          lineHeight: 1.55,
+          resize: 'vertical',
+          outline: 'none',
+        }}
+      />
+      {error && (
+        <p
+          id={`${id}-err`}
+          className="label-system"
+          style={{ color: 'var(--state-failed)' }}
+        >
+          {error}
+        </p>
+      )}
+    </div>
+  );
+}
diff --git a/frontend/src/screens/engagements/EngagementsPage.tsx b/frontend/src/screens/engagements/EngagementsPage.tsx
index c4de7d2..d6a795e 100644
--- a/frontend/src/screens/engagements/EngagementsPage.tsx
+++ b/frontend/src/screens/engagements/EngagementsPage.tsx
@@ -1,12 +1,15 @@
-import type { ReactNode } from 'react';
+import { useState, type ReactNode } from 'react';
 import { Link } from 'react-router-dom';
+import { useQuery } from '@tanstack/react-query';
 import { Panel } from '@/components/ui/Panel';
 import { Pill } from '@/components/ui/Pill';
 import { Button } from '@/components/ui/Button';
-import { MOCK_ENGAGEMENTS } from '@/mocks/fixtures';
-import type { MockEngagement } from '@/mocks/fixtures';
+import { ApiClientError } from '@/lib/api';
+import type { Engagement, EngagementStatus } from '@/types/api';
+import { ENGAGEMENTS_QUERY_KEY, fetchEngagements } from './engagementsApi';
+import { EngagementCreateDialog } from './EngagementCreateDialog';
 
-const STATUS_TONE: Record<MockEngagement['status'], 'running' | 'soc' | 'success' | 'pending'> = {
+const STATUS_TONE: Record<EngagementStatus, 'running' | 'soc' | 'success' | 'pending'> = {
   active: 'running',
   reporting: 'soc',
   archived: 'pending',
@@ -14,12 +17,24 @@ const STATUS_TONE: Record<MockEngagement['status'], 'running' | 'soc' | 'success
 };
 
 export function EngagementsPage() {
+  const [createOpen, setCreateOpen] = useState(false);
+
+  const query = useQuery<Engagement[]>({
+    queryKey: ENGAGEMENTS_QUERY_KEY,
+    queryFn: ({ signal }) => fetchEngagements(signal),
+  });
+
+  const engagements = query.data ?? [];
+
   return (
     <div className="px-8 py-6 space-y-6 max-w-[1400px] mx-auto">
       <header className="flex items-end justify-between">
         <div>
           <div className="label-system mb-1">// Engagements</div>
-          <h1 className="font-display text-fg-default" style={{ fontSize: '22px', letterSpacing: '0.02em' }}>
+          <h1
+            className="font-display text-fg-default"
+            style={{ fontSize: '22px', letterSpacing: '0.02em' }}
+          >
             Mission roster
           </h1>
           <p className="text-fg-muted mt-1" style={{ fontSize: '12.5px' }}>
@@ -27,79 +42,151 @@ export function EngagementsPage() {
             runs, and reports.
           </p>
         </div>
-        <Button variant="primary">+ New engagement</Button>
+        <Button variant="primary" onClick={() => setCreateOpen(true)}>
+          + New engagement
+        </Button>
       </header>
 
       <Panel
         title="Active and recent"
         meta={
           <span className="tabular">
-            {MOCK_ENGAGEMENTS.length} entries · sorted by start date
+            {query.isLoading
+              ? 'loading …'
+              : query.isError
+                ? 'error'
+                : `${String(engagements.length)} entries`}
           </span>
         }
       >
-        <table className="w-full" style={{ fontSize: 12.5 }}>
-          <thead>
-            <tr className="text-fg-subtle">
-              <Th>Codename</Th>
-              <Th>Client</Th>
-              <Th>Status</Th>
-              <Th>C2</Th>
-              <Th align="right">Operators</Th>
-              <Th align="right">SOC</Th>
-              <Th>Window</Th>
-              <Th />
-            </tr>
-          </thead>
-          <tbody>
-            {MOCK_ENGAGEMENTS.map((eng, idx) => (
-              <tr
-                key={eng.id}
-                style={{
-                  borderTop: idx === 0 ? '1px solid var(--line-default)' : '1px solid var(--line-faint)',
-                }}
-              >
-                <Td>
-                  <div className="font-display text-fg-default" style={{ letterSpacing: '0.06em' }}>
-                    {eng.codename}
-                  </div>
-                  <div className="font-mono text-fg-faint" style={{ fontSize: '10.5px' }}>
-                    {eng.id}
-                  </div>
-                </Td>
-                <Td>{eng.client}</Td>
-                <Td>
-                  <Pill tone={STATUS_TONE[eng.status]}>
-                    <span className="status-dot" style={{ color: 'currentColor' }} />
-                    {eng.status}
-                  </Pill>
-                </Td>
-                <Td>
-                  <span className="font-mono tabular">{eng.c2Type.toUpperCase()}</span>
-                </Td>
-                <Td align="right">
-                  <span className="font-mono tabular">{eng.operators}</span>
-                </Td>
-                <Td align="right">
-                  <span className="font-mono tabular">{eng.socAnalysts}</span>
-                </Td>
-                <Td>
-                  <span className="font-mono tabular text-fg-muted">
-                    {eng.startDate} → {eng.endDate}
-                  </span>
-                </Td>
-                <Td align="right">
-                  <Link to="/runs">
-                    <Button variant="ghost" size="sm">
-                      Enter →
-                    </Button>
-                  </Link>
-                </Td>
-              </tr>
-            ))}
-          </tbody>
-        </table>
+        {query.isLoading ? (
+          <LoadingRow />
+        ) : query.isError ? (
+          <ErrorRow error={query.error} onRetry={() => void query.refetch()} />
+        ) : engagements.length === 0 ? (
+          <EmptyRow onCreate={() => setCreateOpen(true)} />
+        ) : (
+          <EngagementsTable engagements={engagements} />
+        )}
       </Panel>
+
+      {createOpen && <EngagementCreateDialog onClose={() => setCreateOpen(false)} />}
+    </div>
+  );
+}
+
+function EngagementsTable({ engagements }: { engagements: Engagement[] }) {
+  return (
+    <table className="w-full" style={{ fontSize: 12.5 }}>
+      <thead>
+        <tr className="text-fg-subtle">
+          <Th>Name</Th>
+          <Th>Client</Th>
+          <Th>Status</Th>
+          <Th>C2</Th>
+          <Th>Window</Th>
+          <Th />
+        </tr>
+      </thead>
+      <tbody>
+        {engagements.map((eng, idx) => (
+          <tr
+            key={eng.id}
+            style={{
+              borderTop:
+                idx === 0 ? '1px solid var(--line-default)' : '1px solid var(--line-faint)',
+            }}
+          >
+            <Td>
+              <div
+                className="font-display text-fg-default"
+                style={{ letterSpacing: '0.06em' }}
+              >
+                {eng.name}
+              </div>
+              <div className="font-mono text-fg-faint" style={{ fontSize: '10.5px' }}>
+                {eng.id}
+              </div>
+            </Td>
+            <Td>{eng.client_name ?? <span className="text-fg-faint">—</span>}</Td>
+            <Td>
+              <Pill tone={STATUS_TONE[eng.status]}>
+                <span className="status-dot" style={{ color: 'currentColor' }} />
+                {eng.status}
+              </Pill>
+            </Td>
+            <Td>
+              {eng.c2_type ? (
+                <span className="font-mono tabular">{eng.c2_type.toUpperCase()}</span>
+              ) : (
+                <span className="text-fg-faint">—</span>
+              )}
+            </Td>
+            <Td>
+              {eng.start_date || eng.end_date ? (
+                <span className="font-mono tabular text-fg-muted">
+                  {eng.start_date ?? '—'} → {eng.end_date ?? '—'}
+                </span>
+              ) : (
+                <span className="text-fg-faint">—</span>
+              )}
+            </Td>
+            <Td align="right">
+              <Link to="/runs">
+                <Button variant="ghost" size="sm">
+                  Enter →
+                </Button>
+              </Link>
+            </Td>
+          </tr>
+        ))}
+      </tbody>
+    </table>
+  );
+}
+
+function LoadingRow() {
+  return (
+    <div className="px-4 py-12 flex items-center gap-3 text-fg-faint label-system">
+      <span className="status-dot text-fg-faint pulsing" />
+      <span>fetching engagements …</span>
+    </div>
+  );
+}
+
+function ErrorRow({ error, onRetry }: { error: unknown; onRetry: () => void }) {
+  const message =
+    error instanceof ApiClientError
+      ? `HTTP ${String(error.status)} · ${error.message}`
+      : 'Unable to reach the backend.';
+  return (
+    <div className="px-4 py-8 flex items-center justify-between gap-4">
+      <div>
+        <div className="label-system" style={{ color: 'var(--state-failed)' }}>
+          // Fetch failed
+        </div>
+        <div className="text-fg-muted mt-1" style={{ fontSize: 12.5 }}>
+          {message}
+        </div>
+      </div>
+      <Button variant="ghost" size="sm" onClick={onRetry}>
+        ↻ Retry
+      </Button>
+    </div>
+  );
+}
+
+function EmptyRow({ onCreate }: { onCreate: () => void }) {
+  return (
+    <div className="px-4 py-12 flex flex-col items-start gap-3">
+      <div className="label-system">// No engagements yet</div>
+      <p className="text-fg-muted" style={{ fontSize: 12.5 }}>
+        Create your first engagement to start composing scenarios and running them against client
+        infrastructure.
+      </p>
+      <Button variant="primary" size="sm" onClick={onCreate}>
+        + New engagement
+      </Button>
     </div>
   );
 }
diff --git a/frontend/src/screens/engagements/engagementsApi.ts b/frontend/src/screens/engagements/engagementsApi.ts
new file mode 100644
index 0000000..4f75566
--- /dev/null
+++ b/frontend/src/screens/engagements/engagementsApi.ts
@@ -0,0 +1,21 @@
+import { apiFetch } from '@/lib/api';
+import type { Engagement, EngagementCreate } from '@/types/api';
+
+export const ENGAGEMENTS_QUERY_KEY = ['engagements'] as const;
+
+/**
+ * GET /api/v1/engagements
+ *
+ * Backend may return either a bare array or a `{ items: [...] }` envelope.
+ * Sprint 1 unwraps both shapes so the UI doesn't have to care which one
+ * landed — the OpenAPI source of truth is on backend's roadmap.
+ */
+export async function fetchEngagements(signal?: AbortSignal): Promise<Engagement[]> {
+  const data = await apiFetch<Engagement[] | { items: Engagement[] }>('/engagements', { signal });
+  if (Array.isArray(data)) return data;
+  return data.items;
+}
+
+export async function createEngagement(payload: EngagementCreate): Promise<Engagement> {
+  return apiFetch<Engagement>('/engagements', { method: 'POST', body: payload });
+}
diff --git a/frontend/src/screens/login/LoginPage.tsx b/frontend/src/screens/login/LoginPage.tsx
index 3c989d3..8f836de 100644
--- a/frontend/src/screens/login/LoginPage.tsx
+++ b/frontend/src/screens/login/LoginPage.tsx
@@ -1,42 +1,68 @@
-import { useState, type FormEvent, type ReactNode } from 'react';
+import { useState, type FormEvent } from 'react';
 import { useNavigate } from 'react-router-dom';
+import { useMutation, useQueryClient } from '@tanstack/react-query';
 import { Logo } from '@/components/brand/Logo';
 import { Button } from '@/components/ui/Button';
 import { Pill } from '@/components/ui/Pill';
-import { useSession } from '@/session/useSession';
-import { MOCK_SESSIONS } from '@/mocks/session';
-import type { Role } from '@/types/roles';
+import { ApiClientError } from '@/lib/api';
+import { login } from '@/session/sessionApi';
+import { SESSION_QUERY_KEY } from '@/session/useSession';
 
 type Mode = 'rt' | 'soc';
 
 /**
  * Login screen — two distinct paths.
  *
- * RT operators authenticate via username/password (D-003 v1, OIDC v2).
- * SOC analysts use a one-shot token (D-006: bcrypt-hashed soc_session,
- * clear value delivered out-of-band by the lead RT).
+ * Sprint 1 wires the RT operator path against POST /api/v1/auth/login.
+ * The SOC analyst path stays visible (so the masthead doesn't change) but
+ * is deferred to sprint 2 when the backend exposes /auth/soc/session.
  *
- * Sprint 0 mock: no validation. Picking a role assumes that role's mock
- * session and lands the user inside the shell.
+ * On success the server sets an HttpOnly session cookie; the response body
+ * is the User. We seed the TanStack Query cache directly so the next render
+ * pass already has the user, then navigate to /engagements (the post-login
+ * landing for RT). No localStorage, no client-side credential persistence.
+ *
+ * Error policy: we never echo the backend message verbatim (could leak
+ * "user not found" vs "wrong password"). 401 → generic "Identifiants
+ * invalides". 4xx/5xx other → generic "Connexion impossible".
  */
 export function LoginPage() {
   const [mode, setMode] = useState<Mode>('rt');
-  const [pickedRtRole, setPickedRtRole] = useState<'rt_operator' | 'rt_lead'>('rt_lead');
-  const { signIn } = useSession();
+  const [username, setUsername] = useState('');
+  const [password, setPassword] = useState('');
+  const [errorMsg, setErrorMsg] = useState<string | null>(null);
+
   const navigate = useNavigate();
+  const queryClient = useQueryClient();
+
+  const loginMutation = useMutation({
+    mutationFn: login,
+    onSuccess: (user) => {
+      queryClient.setQueryData(SESSION_QUERY_KEY, user);
+      setErrorMsg(null);
+      void navigate('/engagements', { replace: true });
+    },
+    onError: (err) => {
+      if (err instanceof ApiClientError && err.status === 401) {
+        setErrorMsg('Identifiants invalides.');
+      } else {
+        setErrorMsg('Connexion impossible. Réessayez dans un instant.');
+      }
+    },
+  });
 
   const handleSubmit = (e: FormEvent) => {
     e.preventDefault();
-    const role: Role = mode === 'soc' ? 'soc_analyst' : pickedRtRole;
-    const user = MOCK_SESSIONS[role];
-    if (!user) return;
-    signIn(user);
-    void navigate(mode === 'soc' ? '/runs' : '/engagements', { replace: true });
+    if (mode !== 'rt') return;
+    if (!username || !password) {
+      setErrorMsg('Nom d’utilisateur et mot de passe requis.');
+      return;
+    }
+    loginMutation.mutate({ username, password });
   };
 
   return (
     <div className="min-h-screen flex" style={{ backgroundColor: 'var(--surface-0)' }}>
-      {/* Left rail — masthead, identity, telemetry of the platform itself */}
       <aside
         className="hidden lg:flex flex-col justify-between w-[420px] border-r p-10"
         style={{
@@ -61,18 +87,14 @@ export function LoginPage() {
           </div>
 
           <div className="space-y-3 font-mono tabular text-fg-faint" style={{ fontSize: '11px' }}>
-            <div className="flex gap-3">
-              <span className="w-24 text-fg-subtle">spec</span>
-              <span>ready-with-prereqs · frozen 2026-05-19</span>
-            </div>
-            <div className="flex gap-3">
-              <span className="w-24 text-fg-subtle">blockers</span>
-              <span>PR1 · PR2 · PR3 (graphic charter)</span>
-            </div>
             <div className="flex gap-3">
               <span className="w-24 text-fg-subtle">deploy</span>
               <span>RT infra · Caddy + TLS · OPSEC handled by RP</span>
             </div>
+            <div className="flex gap-3">
+              <span className="w-24 text-fg-subtle">auth</span>
+              <span>local user/password v1 · OIDC v2</span>
+            </div>
           </div>
         </div>
 
@@ -82,10 +104,8 @@ export function LoginPage() {
         </div>
       </aside>
 
-      {/* Right column — the auth form, instrument-panel inset card */}
       <div className="flex-1 flex items-center justify-center px-8 py-16">
         <div className="w-full max-w-[420px]">
-          {/* Mode switch — segmented, role-tinted */}
           <div className="flex items-center gap-1 mb-6" role="tablist" aria-label="Login mode">
             <ModeTab
               active={mode === 'rt'}
@@ -99,7 +119,7 @@ export function LoginPage() {
               onClick={() => setMode('soc')}
               tone="soc"
               label="SOC — analyst"
-              hint="session token"
+              hint="session token (sprint 2)"
             />
           </div>
 
@@ -114,24 +134,64 @@ export function LoginPage() {
             }}
           >
             <div className="flex items-center justify-between mb-4">
-              <h1 className="font-display text-fg-default" style={{ fontSize: '15px', letterSpacing: '0.05em' }}>
+              <h1
+                className="font-display text-fg-default"
+                style={{ fontSize: '15px', letterSpacing: '0.05em' }}
+              >
                 {mode === 'rt' ? 'Operator sign-in' : 'SOC session'}
               </h1>
               <Pill tone={mode}>{mode === 'rt' ? 'RT' : 'SOC'}</Pill>
             </div>
 
             {mode === 'rt' ? (
-              <RtForm picked={pickedRtRole} onPick={setPickedRtRole} />
+              <div className="space-y-4">
+                <Field
+                  label="Username"
+                  name="username"
+                  autoComplete="username"
+                  value={username}
+                  onChange={setUsername}
+                  disabled={loginMutation.isPending}
+                />
+                <Field
+                  label="Password"
+                  name="password"
+                  type="password"
+                  autoComplete="current-password"
+                  value={password}
+                  onChange={setPassword}
+                  disabled={loginMutation.isPending}
+                />
+              </div>
             ) : (
-              <SocForm />
+              <SocPlaceholder />
+            )}
+
+            {errorMsg && mode === 'rt' && (
+              <p
+                role="alert"
+                className="mt-4 label-system"
+                style={{
+                  color: 'var(--state-failed)',
+                  border: '1px solid var(--state-failed)',
+                  padding: '6px 10px',
+                  borderRadius: 'var(--radius-sm)',
+                }}
+              >
+                {errorMsg}
+              </p>
             )}
 
             <div className="mt-6 flex items-center justify-between gap-3">
               <p className="label-system text-fg-faint">
                 {mode === 'rt' ? 'OIDC Keycloak — v2' : 'Token delivered out-of-band'}
               </p>
-              <Button type="submit" variant="primary">
-                {mode === 'rt' ? 'Enter Mimic →' : 'Open session →'}
+              <Button
+                type="submit"
+                variant="primary"
+                disabled={mode !== 'rt' || loginMutation.isPending}
+              >
+                {loginMutation.isPending ? 'Authenticating …' : 'Enter Mimic →'}
               </Button>
             </div>
           </form>
@@ -140,7 +200,7 @@ export function LoginPage() {
             className="mt-6 font-mono text-fg-faint text-center"
             style={{ fontSize: '10.5px', letterSpacing: '0.08em' }}
           >
-            mimic.rt.local · session ssrf-protected · audit log live
+            mimic.rt.local · session cookie HttpOnly · audit log live
           </p>
         </div>
       </div>
@@ -178,7 +238,13 @@ function ModeTab({ active, onClick, tone, label, hint }: ModeTabProps) {
     >
       <div
         className="label-system"
-        style={{ color: active ? (tone === 'rt' ? 'var(--accent-rt)' : 'var(--accent-soc)') : 'var(--fg-subtle)' }}
+        style={{
+          color: active
+            ? tone === 'rt'
+              ? 'var(--accent-rt)'
+              : 'var(--accent-soc)'
+            : 'var(--fg-subtle)',
+        }}
       >
         {label}
       </div>
@@ -189,75 +255,47 @@ function ModeTab({ active, onClick, tone, label, hint }: ModeTabProps) {
   );
 }
 
-function RtForm({
-  picked,
-  onPick,
-}: {
-  picked: 'rt_operator' | 'rt_lead';
-  onPick: (r: 'rt_operator' | 'rt_lead') => void;
-}) {
+function SocPlaceholder() {
   return (
-    <div className="space-y-4">
-      <Field label="Username" placeholder="m.dubreuil" autoComplete="username" />
-      <Field label="Password" type="password" placeholder="••••••••••" autoComplete="current-password" />
-      <fieldset className="space-y-2">
-        <legend className="label-system">Mock role (sprint 0 only)</legend>
-        <div className="flex gap-2">
-          <RolePick active={picked === 'rt_operator'} onClick={() => onPick('rt_operator')}>
-            RT Operator
-          </RolePick>
-          <RolePick active={picked === 'rt_lead'} onClick={() => onPick('rt_lead')}>
-            RT Lead
-          </RolePick>
-        </div>
-      </fieldset>
-    </div>
-  );
-}
-
-function SocForm() {
-  return (
-    <div className="space-y-4">
-      <Field
-        label="Session token"
-        placeholder="msoc_xxxxx-xxxx-xxxx-xxxx"
-        autoComplete="off"
-        spellCheck={false}
-        mono
-      />
-      <p className="font-mono text-fg-faint" style={{ fontSize: '10.5px', lineHeight: 1.5 }}>
-        Your token was delivered out-of-band by the lead RT.
-        <br />
-        Scope: <span className="text-fg-muted">single engagement, read-only on telemetry, write on detection coting.</span>
-      </p>
-    </div>
+    <p
+      className="font-mono text-fg-faint"
+      style={{ fontSize: '11px', lineHeight: 1.55 }}
+    >
+      SOC session sign-in lands in sprint 2 once the backend exposes
+      <br />
+      <code style={{ fontSize: '10.5px' }}>POST /api/v1/auth/soc/session</code>.
+      <br />
+      For now, use the RT path with a local account.
+    </p>
   );
 }
 
 interface FieldProps {
   label: string;
-  placeholder?: string;
+  name: string;
   type?: string;
   autoComplete?: string;
-  spellCheck?: boolean;
-  mono?: boolean;
+  value: string;
+  onChange: (next: string) => void;
+  disabled?: boolean;
 }
 
-function Field({ label, placeholder, type = 'text', autoComplete, spellCheck, mono }: FieldProps) {
-  const id = label.toLowerCase().replace(/\s+/g, '-');
+function Field({ label, name, type = 'text', autoComplete, value, onChange, disabled }: FieldProps) {
   return (
     <div>
-      <label htmlFor={id} className="block label-system mb-1.5">
+      <label htmlFor={name} className="block label-system mb-1.5">
         {label}
       </label>
       <input
-        id={id}
-        name={id}
+        id={name}
+        name={name}
         type={type}
-        placeholder={placeholder}
         autoComplete={autoComplete}
-        spellCheck={spellCheck}
-        className={mono ? 'font-mono' : 'font-sans'}
+        value={value}
+        onChange={(e) => onChange(e.target.value)}
+        disabled={disabled}
+        required
+        className="font-sans"
         style={{
           width: '100%',
           height: 32,
@@ -272,29 +310,3 @@ function Field({ label, placeholder, type = 'text', autoComplete, spellCheck, mo
     </div>
   );
 }
-
-function RolePick({
-  active,
-  onClick,
-  children,
-}: {
-  active: boolean;
-  onClick: () => void;
-  children: ReactNode;
-}) {
-  return (
-    <button
-      type="button"
-      onClick={onClick}
-      className="flex-1 label-system px-3 py-2 transition-colors"
-      style={{
-        background: active ? 'oklch(74.0% 0.165 68 / 0.10)' : 'transparent',
-        color: active ? 'var(--accent-rt)' : 'var(--fg-muted)',
-        border: `1px solid ${active ? 'var(--accent-rt-muted)' : 'var(--line-default)'}`,
-        borderRadius: 'var(--radius-sm)',
-      }}
-    >
-      {children}
-    </button>
-  );
-}