diff --git a/src/data/abac.js b/src/data/abac.js
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+++ b/src/data/abac.js
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+// src/data/abac.js
+// Pure attribute-based access-control engine (COSMETIC / frontend-only — a demonstration of the
+// access model against the mock store; the real policy enforcement is backend, owned by another team).
+// A decision evaluates ordered policies over { subject, action, resource, ctx }.
+// DENY WINS; DEFAULT DENY.
+// A policy: { id, effect: 'permit' | 'deny', when: (subject, action, resource, ctx) => boolean }
+
+export function evaluate(policies, subject, action, resource = {}, ctx = {}) {
+  let permitted = false;
+  let denied = false;
+  for (const p of policies) {
+    let match;
+    try { match = p.when(subject, action, resource, ctx); } catch { match = false; }
+    if (!match) continue;
+    if (p.effect === 'deny') denied = true;
+    else permitted = true;
+  }
+  return !denied && permitted; // deny wins; default deny
+}
+
+// Build the subject (attributes) from the auth user + resolved org role key.
+export function buildSubject(user, orgRoleKey) {
+  return {
+    id: user?.id,
+    role: user?.role,
+    orgRole: orgRoleKey,            // OWNER | ADMIN | SALES_REP | CANVASSER | SUBCONTRACTOR
+    team: user?.team,
+    territory: user?.territory,
+  };
+}
+
+// Normalize a resource arg into { module, type, ...attrs } the policies read.
+// Accepts a domain object (project / lead / task) OR a plain { module } for route/module checks.
+export function normalizeResource(resource) {
+  if (!resource) return { module: undefined };
+  // a project
+  if (resource.id && (resource.ownerId || resource.subcontractorIds || resource.teamMembers)) {
+    return {
+      module: 'jobs', type: 'project',
+      ownerId: resource.ownerId,
+      subcontractorIds: resource.subcontractorIds || [],
+      teamUserIds: (resource.teamMembers || []).map(t => t.userId),
+      status: resource.status, value: resource.budget,
+    };
+  }
+  // a lead
+  if (resource.assignedAgentId !== undefined || resource.columnId !== undefined) {
+    return { module: 'leads', type: 'lead', assignedAgentId: resource.assignedAgentId };
+  }
+  // a subcontractor task
+  if (resource.subcontractorId !== undefined && resource.title !== undefined) {
+    return { module: 'subcontractor_tasks', type: 'task', subcontractorId: resource.subcontractorId };
+  }
+  // already a { module } (route/module-level check)
+  return { module: resource.module || resource.type, type: resource.type };
+}
+
+// Compile the RBAC data + resource-aware rules into an ordered policy list.
+// orgPermissions: { module: { ROLE: [actions] } }; overrides: [{ userId, moduleKey, action, effect }]
+export function compilePolicies(orgPermissions = {}, overrides = []) {
+  const policies = [];
+
+  // 1) Blanket OWNER permit (owners see/do everything).
+  policies.push({ id: 'owner-all', effect: 'permit', when: (s) => s.orgRole === 'OWNER' });
+
+  // 2) Baseline role×module permits from the matrix.
+  for (const [module, roleMap] of Object.entries(orgPermissions)) {
+    for (const [role, actions] of Object.entries(roleMap)) {
+      for (const action of actions) {
+        policies.push({
+          id: `base:${module}:${role}:${action}`,
+          effect: 'permit',
+          when: (s, a, r) => s.orgRole === role && r.module === module && a === action,
+        });
+      }
+    }
+  }
+
+  // 3) Resource-aware rules (the ABAC layer).
+  // Sales rep may EDIT a project only if assigned (on the team).
+  policies.push({
+    id: 'rep-edit-assigned-only',
+    effect: 'deny',
+    when: (s, a, r) => s.orgRole === 'SALES_REP' && r.module === 'jobs' && a === 'edit'
+      && r.type === 'project' && !(r.teamUserIds || []).includes(s.id),
+  });
+  // Subcontractor may VIEW only projects they're on.
+  policies.push({
+    id: 'sub-view-own-projects',
+    effect: 'permit',
+    when: (s, a, r) => s.orgRole === 'SUBCONTRACTOR' && r.module === 'jobs' && a === 'view'
+      && r.type === 'project' && (r.subcontractorIds || []).includes(s.id),
+  });
+  // Canvasser may EDIT only leads they sourced.
+  policies.push({
+    id: 'canvasser-edit-own-leads',
+    effect: 'permit',
+    when: (s, a, r) => s.orgRole === 'CANVASSER' && r.module === 'leads' && a === 'edit'
+      && r.type === 'lead' && r.assignedAgentId === s.id,
+  });
+
+  // 4) Per-person overrides (grant/deny) — deny wins via evaluate().
+  for (const o of overrides) {
+    policies.push({
+      id: `override:${o.userId}:${o.moduleKey}:${o.action}:${o.effect}`,
+      effect: o.effect === 'deny' ? 'deny' : 'permit',
+      when: (s, a, r) => s.id === o.userId && r.module === o.moduleKey && a === o.action,
+    });
+  }
+
+  return policies;
+}