diff --git a/package-lock.json b/package-lock.json
index ec2eb147..bd4628dd 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -4538,14 +4538,14 @@
       "version": "15.7.15",
       "resolved": "https://registry.npmjs.org/@types/prop-types/-/prop-types-15.7.15.tgz",
       "integrity": "sha512-F6bEyamV9jKGAFBEmlQnesRPGOQqS2+Uwi0Em15xenOxHaf2hv6L8YCVn3rPdPJOiJfPiCnLIRyvwVaqMY3MIw==",
-      "devOptional": true,
+      "dev": true,
       "license": "MIT"
     },
     "node_modules/@types/react": {
       "version": "18.3.28",
       "resolved": "https://registry.npmjs.org/@types/react/-/react-18.3.28.tgz",
       "integrity": "sha512-z9VXpC7MWrhfWipitjNdgCauoMLRdIILQsAEV+ZesIzBq/oUlxk0m3ApZuMFCXdnS4U7KrI+l3WRUEGQ8K1QKw==",
-      "devOptional": true,
+      "dev": true,
       "license": "MIT",
       "dependencies": {
         "@types/prop-types": "*",
@@ -11595,7 +11595,7 @@
       "version": "6.0.3",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-6.0.3.tgz",
       "integrity": "sha512-y2TvuxSZPDyQakkFRPZHKFm+KKVqIisdg9/CZwm9ftvKXLP8NRWj38/ODjNbr43SsoXqNuAisEf1GdCxqWcdBw==",
-      "devOptional": true,
+      "dev": true,
       "license": "Apache-2.0",
       "bin": {
         "tsc": "bin/tsc",
diff --git a/src/lib/advancedSearch.js b/src/lib/advancedSearch.ts
similarity index 100%
rename from src/lib/advancedSearch.js
rename to src/lib/advancedSearch.ts
diff --git a/src/lib/alertRulesDb.js b/src/lib/alertRulesDb.ts
similarity index 100%
rename from src/lib/alertRulesDb.js
rename to src/lib/alertRulesDb.ts
diff --git a/src/lib/alerts.js b/src/lib/alerts.ts
similarity index 100%
rename from src/lib/alerts.js
rename to src/lib/alerts.ts
diff --git a/src/lib/analytics.js b/src/lib/analytics.ts
similarity index 100%
rename from src/lib/analytics.js
rename to src/lib/analytics.ts
diff --git a/src/lib/anchors.js b/src/lib/anchors.ts
similarity index 100%
rename from src/lib/anchors.js
rename to src/lib/anchors.ts
diff --git a/src/lib/auditTrail.js b/src/lib/auditTrail.ts
similarity index 100%
rename from src/lib/auditTrail.js
rename to src/lib/auditTrail.ts
diff --git a/src/lib/cache.js b/src/lib/cache.ts
similarity index 100%
rename from src/lib/cache.js
rename to src/lib/cache.ts
diff --git a/src/lib/chartUtils.js b/src/lib/chartUtils.ts
similarity index 100%
rename from src/lib/chartUtils.js
rename to src/lib/chartUtils.ts
diff --git a/src/lib/config.js b/src/lib/config.ts
similarity index 100%
rename from src/lib/config.js
rename to src/lib/config.ts
diff --git a/src/lib/contractDevelopment.js b/src/lib/contractDevelopment.ts
similarity index 100%
rename from src/lib/contractDevelopment.js
rename to src/lib/contractDevelopment.ts
diff --git a/src/lib/contractInvoker.js b/src/lib/contractInvoker.ts
similarity index 100%
rename from src/lib/contractInvoker.js
rename to src/lib/contractInvoker.ts
diff --git a/src/lib/dex.js b/src/lib/dex.ts
similarity index 100%
rename from src/lib/dex.js
rename to src/lib/dex.ts
diff --git a/src/lib/encryption.js b/src/lib/encryption.ts
similarity index 100%
rename from src/lib/encryption.js
rename to src/lib/encryption.ts
diff --git a/src/lib/errorReporting.js b/src/lib/errorReporting.ts
similarity index 100%
rename from src/lib/errorReporting.js
rename to src/lib/errorReporting.ts
diff --git a/src/lib/externalExplorers.js b/src/lib/externalExplorers.ts
similarity index 100%
rename from src/lib/externalExplorers.js
rename to src/lib/externalExplorers.ts
diff --git a/src/lib/filters.js b/src/lib/filters.ts
similarity index 78%
rename from src/lib/filters.js
rename to src/lib/filters.ts
index e6855780..753b7d67 100644
--- a/src/lib/filters.js
+++ b/src/lib/filters.ts
@@ -1,9 +1,9 @@
-function toNumber(value, fallback = 0) {
-  const parsed = Number(value);
+function toNumber(value: unknown, fallback = 0) {
+  const parsed = Number(value as any);
   return Number.isFinite(parsed) ? parsed : fallback;
 }
 
-export function applyTransactionFilters(transactions = [], filters = {}) {
+export function applyTransactionFilters(transactions: any[] = [], filters: any = {}) {
   return transactions.filter((tx) => {
     if (filters.status === "success" && !tx.successful) return false;
     if (filters.status === "failed" && tx.successful) return false;
@@ -22,7 +22,7 @@ export function applyTransactionFilters(transactions = [], filters = {}) {
   });
 }
 
-export function applyOperationFilters(operations = [], filters = {}) {
+export function applyOperationFilters(operations: any[] = [], filters: any = {}) {
   return operations.filter((op) => {
     if (filters.type && filters.type !== "all" && op.type !== filters.type) {
       return false;
@@ -34,7 +34,7 @@ export function applyOperationFilters(operations = [], filters = {}) {
   });
 }
 
-export function applyAssetFilters(assets = [], filters = {}) {
+export function applyAssetFilters(assets: any[] = [], filters: any = {}) {
   return assets.filter((asset) => {
     if (filters.verifiedOnly && !asset.is_verified) return false;
     if (filters.minHolders && toNumber(asset.num_accounts) < toNumber(filters.minHolders)) {
diff --git a/src/lib/import.js b/src/lib/import.ts
similarity index 100%
rename from src/lib/import.js
rename to src/lib/import.ts
diff --git a/src/lib/multisig.js b/src/lib/multisig.ts
similarity index 100%
rename from src/lib/multisig.js
rename to src/lib/multisig.ts
diff --git a/src/lib/networkMonitoring.js b/src/lib/networkMonitoring.ts
similarity index 100%
rename from src/lib/networkMonitoring.js
rename to src/lib/networkMonitoring.ts
diff --git a/src/lib/notifications.js b/src/lib/notifications.ts
similarity index 100%
rename from src/lib/notifications.js
rename to src/lib/notifications.ts
diff --git a/src/lib/performanceMonitoring.js b/src/lib/performanceMonitoring.ts
similarity index 100%
rename from src/lib/performanceMonitoring.js
rename to src/lib/performanceMonitoring.ts
diff --git a/src/lib/portfolioAnalytics.js b/src/lib/portfolioAnalytics.ts
similarity index 100%
rename from src/lib/portfolioAnalytics.js
rename to src/lib/portfolioAnalytics.ts
diff --git a/src/lib/priceFeed.js b/src/lib/priceFeed.ts
similarity index 100%
rename from src/lib/priceFeed.js
rename to src/lib/priceFeed.ts
diff --git a/src/lib/rateLimiter.js b/src/lib/rateLimiter.ts
similarity index 87%
rename from src/lib/rateLimiter.js
rename to src/lib/rateLimiter.ts
index 7a2a78ee..d879cf69 100644
--- a/src/lib/rateLimiter.js
+++ b/src/lib/rateLimiter.ts
@@ -3,16 +3,79 @@
  * Implements token bucket algorithm with intelligent request batching and queue management
  */
 
+type RequestPriority = 'high' | 'medium' | 'low';
+
+type ThrottleMode = 'aggressive' | 'conservative';
+
+interface RequestPayload {
+  url: string;
+  options?: RequestInit;
+  priority?: RequestPriority;
+  maxRetries?: number;
+  method?: string;
+}
+
+interface QueuedRequest {
+  id: string;
+  request: RequestPayload;
+  identifier: string;
+  timestamp: number;
+  resolve?: (value: Response | PromiseLike<Response>) => void;
+  reject?: (reason?: any) => void;
+  priority: RequestPriority;
+  endpoint: string;
+  retryCount: number;
+  maxRetries: number;
+}
+
+interface RateLimitBucket {
+  tokens: number;
+  lastRefill: number;
+  endpointUsage: Map<string, number>;
+}
+
+interface RateLimiterStats {
+  totalRequests: number;
+  queuedRequests: number;
+  batchedRequests: number;
+  rejectedRequests: number;
+  droppedRequests: number;
+  averageResponseTime: number;
+  endpointUsage: Map<string, number>;
+}
+
+interface RateLimiterOptions {
+  windowMs?: number;
+  maxRequests?: number;
+  batchSize?: number;
+  batchTimeout?: number;
+  throttleMode?: ThrottleMode;
+  maxQueueSize?: number;
+}
+
 class RateLimiter {
-  constructor(options = {}) {
-    this.windowMs = options.windowMs || 60000; // Default: 1 minute
-    this.maxRequests = options.maxRequests || 30; // Default: 30 requests per minute
+  private windowMs: number;
+  private maxRequests: number;
+  private buckets: Map<string, RateLimitBucket>;
+  private requestQueue: Map<string, QueuedRequest[]>;
+  private batchSize: number;
+  private batchTimeout: number;
+  private throttleMode: ThrottleMode;
+  private maxQueueSize: number;
+  private priorityQueues: Record<RequestPriority, QueuedRequest[]>;
+  private cleanupInterval: ReturnType<typeof setInterval>;
+  private processingInterval: ReturnType<typeof setInterval>;
+  private statistics: RateLimiterStats;
+
+  constructor(options: RateLimiterOptions = {}) {
+    this.windowMs = options.windowMs ?? 60000; // Default: 1 minute
+    this.maxRequests = options.maxRequests ?? 30; // Default: 30 requests per minute
     this.buckets = new Map(); // Store tokens per user/IP
     this.requestQueue = new Map(); // Request queues per endpoint type
-    this.batchSize = options.batchSize || 10; // Max batch size for request batching
-    this.batchTimeout = options.batchTimeout || 100; // Max wait time for batching (ms)
-    this.throttleMode = options.throttleMode || 'aggressive'; // 'aggressive' | 'conservative'
-    this.maxQueueSize = options.maxQueueSize || 100; // Maximum items in queue before dropping
+    this.batchSize = options.batchSize ?? 10; // Max batch size for request batching
+    this.batchTimeout = options.batchTimeout ?? 100; // Max wait time for batching (ms)
+    this.throttleMode = options.throttleMode ?? 'aggressive'; // 'aggressive' | 'conservative'
+    this.maxQueueSize = options.maxQueueSize ?? 100; // Maximum items in queue before dropping
     this.priorityQueues = {
       high: [],
       medium: [],
@@ -45,6 +108,7 @@ class RateLimiter {
       bucket = {
         tokens: this.maxRequests - 1,
         lastRefill: now,
+        endpointUsage: new Map()
       };
       this.buckets.set(identifier, bucket);
       
diff --git a/src/lib/securityEvents.js b/src/lib/securityEvents.ts
similarity index 86%
rename from src/lib/securityEvents.js
rename to src/lib/securityEvents.ts
index 62731e69..d43235f0 100644
--- a/src/lib/securityEvents.js
+++ b/src/lib/securityEvents.ts
@@ -12,6 +12,27 @@ import {
   AuditSeverity,
   subscribeAudit,
 } from '../utils/audit.js';
+import type {
+  AuditSeverity as AuditSeverityType,
+  AuditCategory as AuditCategoryType,
+  AuditOutcome,
+} from '../utils/audit.js';
+
+export interface SecurityEventOptions {
+  actor?: string;
+  target?: string;
+  outcome?: AuditOutcome;
+  metadata?: Record<string, unknown>;
+  severityOverride?: AuditSeverityType;
+}
+
+interface SecurityAlert {
+  kind: string;
+  actor: string;
+  count: number;
+  windowMs: number;
+  action?: string;
+}
 
 // ─── Canonical security event types ──────────────────────────────────────────
 
@@ -91,31 +112,31 @@ function categoryFor(eventType) {
 
 // ─── Anomaly detection state ─────────────────────────────────────────────────
 
-const _failedAuthByActor = new Map();         // actor -> timestamps
-const _ratelimitHitsByAction = new Map();     // action -> timestamps
+const _failedAuthByActor = new Map<string, number[]>();         // actor -> timestamps
+const _ratelimitHitsByAction = new Map<string, number[]>();     // action -> timestamps
 const FAILED_AUTH_WINDOW_MS = 5 * 60_000;
 const FAILED_AUTH_THRESHOLD = 5;
 const RATE_LIMIT_WINDOW_MS = 10 * 60_000;
 const RATE_LIMIT_THRESHOLD = 10;
 
-const _alertSubscribers = new Set();
+const _alertSubscribers = new Set<(alert: SecurityAlert) => void>();
 
-export function subscribeSecurityAlerts(handler) {
+export function subscribeSecurityAlerts(handler: (alert: SecurityAlert) => void) {
   _alertSubscribers.add(handler);
   return () => _alertSubscribers.delete(handler);
 }
 
-function emitAlert(alert) {
+function emitAlert(alert: SecurityAlert) {
   for (const fn of _alertSubscribers) {
     try { fn(alert); } catch { /* swallow */ }
   }
 }
 
-function pruneOlderThan(arr, cutoff) {
+function pruneOlderThan(arr: number[], cutoff: number) {
   return arr.filter((t) => t >= cutoff);
 }
 
-function checkAnomalies(eventType, payload) {
+function checkAnomalies(eventType: string, payload: { actor?: string; metadata?: Record<string, unknown> }) {
   const now = Date.now();
 
   if (eventType === SecurityEventType.AUTH_LOGIN_FAILED) {
@@ -146,7 +167,7 @@ function checkAnomalies(eventType, payload) {
   }
 
   if (eventType === SecurityEventType.RATE_LIMIT_HIT) {
-    const action = payload.metadata?.action || 'unknown';
+    const action = typeof payload.metadata?.action === 'string' ? payload.metadata.action : 'unknown';
     const list = pruneOlderThan(
       _ratelimitHitsByAction.get(action) ?? [],
       now - RATE_LIMIT_WINDOW_MS,
@@ -187,7 +208,7 @@ function checkAnomalies(eventType, payload) {
  * }} [opts]
  * @returns {Promise<object>}
  */
-export function trackSecurityEvent(eventType, opts = {}) {
+export function trackSecurityEvent(eventType: string, opts: SecurityEventOptions = {}) {
   const severity = opts.severityOverride ?? SEVERITY_MAP[eventType] ?? AuditSeverity.INFO;
   const category = categoryFor(eventType);
 
diff --git a/src/lib/stellar.ts b/src/lib/stellar.ts
index 943e85be..bb2beec4 100644
--- a/src/lib/stellar.ts
+++ b/src/lib/stellar.ts
@@ -2,7 +2,7 @@ import * as StellarSdk from '@stellar/stellar-sdk'
 import { Cache, TTL } from './cache.js'
 import { rateLimiter } from './rateLimiter.js'
 import auditTrail from './auditTrail.js'
-import { getCircuitBreaker } from './errorHandling/CircuitBreaker'
+import { getCircuitBreaker, type CircuitState } from './errorHandling/CircuitBreaker'
 
 // ─── Cache setup ──────────────────────────────────────────────────────────────
 
diff --git a/src/lib/storage.js b/src/lib/storage.ts
similarity index 86%
rename from src/lib/storage.js
rename to src/lib/storage.ts
index 886436fd..6533d43b 100644
--- a/src/lib/storage.js
+++ b/src/lib/storage.ts
@@ -19,18 +19,33 @@ const STORES = {
   OFFLINE_Q:  'offline-queue', // Queued writes for when back online
 };
 
+interface ApiCacheRecord {
+  key: string;
+  value: unknown;
+  expiresAt: number;
+  tag: string;
+  cachedAt: number;
+}
+
+interface OfflineOp {
+  id?: number;
+  type: string;
+  payload: unknown;
+  queuedAt: number;
+}
+
 // ─── DB open ──────────────────────────────────────────────────────────────────
 
-let _db = null;
+let _db: IDBDatabase | null = null;
 
-function openDB() {
+function openDB(): Promise<IDBDatabase> {
   if (_db) return Promise.resolve(_db);
 
   return new Promise((resolve, reject) => {
     const request = indexedDB.open(DB_NAME, DB_VERSION);
 
     request.onupgradeneeded = (event) => {
-      const db = event.target.result;
+      const db = (event.target as IDBOpenDBRequest).result;
 
       if (!db.objectStoreNames.contains(STORES.APP_STATE)) {
         db.createObjectStore(STORES.APP_STATE);
@@ -66,18 +81,18 @@ function openDB() {
 
 // ─── Generic transaction helper ───────────────────────────────────────────────
 
-async function tx(storeName, mode, fn) {
-  const db       = await openDB();
-  const trans    = db.transaction(storeName, mode);
-  const store    = trans.objectStore(storeName);
-  return new Promise((resolve, reject) => {
-    const req = fn(store);
+async function tx<T = void>(storeName: string, mode: IDBTransactionMode, fn: (store: IDBObjectStore) => IDBRequest<T> | void): Promise<T | void> {
+  const db = await openDB();
+  const trans = db.transaction(storeName, mode);
+  const store = trans.objectStore(storeName);
+  return new Promise<T | void>((resolve, reject) => {
+    const req = fn(store) as IDBRequest<T> | void;
     if (req && typeof req.onsuccess !== 'undefined') {
       req.onsuccess = () => resolve(req.result);
-      req.onerror   = () => reject(req.error);
+      req.onerror = () => reject(req.error);
     } else {
       trans.oncomplete = () => resolve();
-      trans.onerror    = () => reject(trans.error);
+      trans.onerror = () => reject(trans.error);
     }
   });
 }
@@ -127,7 +142,7 @@ export async function clearStorage() {
  */
 export async function getCachedApiResponse(key) {
   try {
-    const record = await tx(STORES.API_CACHE, 'readonly', (s) => s.get(key));
+    const record = await tx<ApiCacheRecord | undefined>(STORES.API_CACHE, 'readonly', (s) => s.get(key));
     if (!record) return null;
     if (Date.now() > record.expiresAt) {
       // Expired — delete lazily
@@ -173,9 +188,9 @@ export async function invalidateCacheByTag(tag) {
 
     await new Promise((resolve, reject) => {
       req.onsuccess = (e) => {
-        const cursor = e.target.result;
+        const cursor = (e.target as IDBRequest).result;
         if (cursor) { cursor.delete(); cursor.continue(); }
-        else resolve();
+        else resolve(undefined);
       };
       req.onerror = () => reject(req.error);
     });
@@ -195,9 +210,9 @@ export async function pruneExpiredApiCache() {
 
     await new Promise((resolve, reject) => {
       req.onsuccess = (e) => {
-        const cursor = e.target.result;
+        const cursor = (e.target as IDBRequest).result;
         if (cursor) { cursor.delete(); cursor.continue(); }
-        else resolve();
+        else resolve(undefined);
       };
       req.onerror = () => reject(req.error);
     });
@@ -210,7 +225,7 @@ export async function pruneExpiredApiCache() {
  * Add an operation to the offline queue (e.g. a transaction to submit later).
  * @param {{ type: string, payload: * }} op
  */
-export async function enqueueOfflineOp(op) {
+export async function enqueueOfflineOp(op: Omit<OfflineOp, 'queuedAt' | 'id'>) {
   try {
     await tx(STORES.OFFLINE_Q, 'readwrite', (s) => s.add({ ...op, queuedAt: Date.now() }));
   } catch { /* ignore */ }
@@ -218,11 +233,12 @@ export async function enqueueOfflineOp(op) {
 
 /**
  * Read all queued offline operations.
- * @returns {Promise<Array>}
+ * @returns {Promise<Array<OfflineOp>>}
  */
-export async function getOfflineQueue() {
+export async function getOfflineQueue(): Promise<OfflineOp[]> {
   try {
-    return await tx(STORES.OFFLINE_Q, 'readonly', (s) => s.getAll()) ?? [];
+    const res = await tx<OfflineOp[]>(STORES.OFFLINE_Q, 'readonly', (s) => s.getAll());
+    return (res as OfflineOp[] | undefined) ?? [];
   } catch { return []; }
 }
 
@@ -230,7 +246,7 @@ export async function getOfflineQueue() {
  * Remove a processed operation from the queue by its auto-increment id.
  * @param {number} id
  */
-export async function dequeueOfflineOp(id) {
+export async function dequeueOfflineOp(id: number) {
   try {
     await tx(STORES.OFFLINE_Q, 'readwrite', (s) => s.delete(id));
   } catch { /* ignore */ }
diff --git a/src/lib/streaming.js b/src/lib/streaming.ts
similarity index 88%
rename from src/lib/streaming.js
rename to src/lib/streaming.ts
index c0803d5e..e7df3ce9 100644
--- a/src/lib/streaming.js
+++ b/src/lib/streaming.ts
@@ -19,20 +19,22 @@ const MAX_RECONNECT_ATTEMPTS = 10
  *   any          → disconnected  (on explicit .disconnect())
  */
 class StreamManager {
+  private _closeStream: (() => void) | null = null
+  private _status: 'disconnected' | 'connecting' | 'connected' | 'reconnecting' | 'error' = 'disconnected'
+  private _reconnectAttempts = 0
+  private _reconnectTimer: ReturnType<typeof setTimeout> | null = null
+  private _network: any | null = null
+  private _ledgerSubscribers: Set<(ledger: any) => void> = new Set()
+  private _statusSubscribers: Set<(status: any) => void> = new Set()
+
   constructor() {
-    /** @type {(() => void) | null} */
     this._closeStream = null
-    /** @type {'disconnected'|'connecting'|'connected'|'reconnecting'|'error'} */
     this._status = 'disconnected'
     this._reconnectAttempts = 0
-    /** @type {ReturnType<typeof setTimeout> | null} */
     this._reconnectTimer = null
-    /** @type {string | null} */
     this._network = null
 
-    /** Ledger callbacks */
     this._ledgerSubscribers = new Set()
-    /** Status-change callbacks */
     this._statusSubscribers = new Set()
   }
 
@@ -44,9 +46,9 @@ class StreamManager {
    * @param {(ledger: object) => void} callback
    * @returns {() => void}
    */
-  subscribe(callback) {
+  subscribe(callback: (ledger: any) => void): () => void {
     this._ledgerSubscribers.add(callback)
-    return () => this._ledgerSubscribers.delete(callback)
+    return () => { this._ledgerSubscribers.delete(callback); }
   }
 
   /**
@@ -55,9 +57,9 @@ class StreamManager {
    * @param {(status: string) => void} callback
    * @returns {() => void}
    */
-  onStatusChange(callback) {
+  onStatusChange(callback: (status: any) => void): () => void {
     this._statusSubscribers.add(callback)
-    return () => this._statusSubscribers.delete(callback)
+    return () => { this._statusSubscribers.delete(callback); }
   }
 
   /** @returns {'disconnected'|'connecting'|'connected'|'reconnecting'|'error'} */
@@ -70,7 +72,7 @@ class StreamManager {
    * Disconnects any existing stream first.
    * @param {string} [network='testnet']
    */
-  connect(network = 'testnet') {
+  connect(network: any = 'testnet') {
     if (this._network !== network && this._closeStream) {
       this.disconnect()
     }
@@ -109,7 +111,7 @@ class StreamManager {
   _openStream() {
     this._setStatus('connecting')
     try {
-      const server = getServer(this._network)
+      const server = getServer(this._network as any)
       this._closeStream = server
         .ledgers()
         .cursor('now')
diff --git a/src/lib/tests/auditTrail.test.js b/src/lib/tests/auditTrail.test.ts
similarity index 100%
rename from src/lib/tests/auditTrail.test.js
rename to src/lib/tests/auditTrail.test.ts
diff --git a/src/lib/transactionBuilder.js b/src/lib/transactionBuilder.ts
similarity index 100%
rename from src/lib/transactionBuilder.js
rename to src/lib/transactionBuilder.ts
diff --git a/src/lib/transactionTemplates.js b/src/lib/transactionTemplates.ts
similarity index 100%
rename from src/lib/transactionTemplates.js
rename to src/lib/transactionTemplates.ts
diff --git a/src/lib/transactionVerification.js b/src/lib/transactionVerification.ts
similarity index 100%
rename from src/lib/transactionVerification.js
rename to src/lib/transactionVerification.ts
diff --git a/src/lib/tutorialSystem.js b/src/lib/tutorialSystem.ts
similarity index 100%
rename from src/lib/tutorialSystem.js
rename to src/lib/tutorialSystem.ts
diff --git a/src/lib/wallet/devices.js b/src/lib/wallet/devices.ts
similarity index 100%
rename from src/lib/wallet/devices.js
rename to src/lib/wallet/devices.ts
diff --git a/src/lib/wallet/freighter.js b/src/lib/wallet/freighter.ts
similarity index 100%
rename from src/lib/wallet/freighter.js
rename to src/lib/wallet/freighter.ts
diff --git a/src/lib/wallet/ledger.js b/src/lib/wallet/ledger.ts
similarity index 100%
rename from src/lib/wallet/ledger.js
rename to src/lib/wallet/ledger.ts
diff --git a/src/lib/wallet/security.js b/src/lib/wallet/security.ts
similarity index 100%
rename from src/lib/wallet/security.js
rename to src/lib/wallet/security.ts
diff --git a/src/lib/websocket.js b/src/lib/websocket.ts
similarity index 100%
rename from src/lib/websocket.js
rename to src/lib/websocket.ts
diff --git a/src/utils/accessibility.js b/src/utils/accessibility.ts
similarity index 100%
rename from src/utils/accessibility.js
rename to src/utils/accessibility.ts
diff --git a/src/utils/analytics.js b/src/utils/analytics.ts
similarity index 100%
rename from src/utils/analytics.js
rename to src/utils/analytics.ts
diff --git a/src/utils/audit.js b/src/utils/audit.ts
similarity index 84%
rename from src/utils/audit.js
rename to src/utils/audit.ts
index 59d70a94..12904819 100644
--- a/src/utils/audit.js
+++ b/src/utils/audit.ts
@@ -20,7 +20,9 @@ export const AuditSeverity = Object.freeze({
   MEDIUM: 'medium',
   HIGH: 'high',
   CRITICAL: 'critical',
-});
+}) as const;
+
+export type AuditSeverity = (typeof AuditSeverity)[keyof typeof AuditSeverity];
 
 export const AuditCategory = Object.freeze({
   AUTH: 'auth',
@@ -34,18 +36,66 @@ export const AuditCategory = Object.freeze({
   SECURITY: 'security',
   ADMIN: 'admin',
   SYSTEM: 'system',
-});
+}) as const;
+
+export type AuditCategory = (typeof AuditCategory)[keyof typeof AuditCategory];
+
+export type AuditOutcome = 'success' | 'failure' | 'denied';
+
+export interface AuditEntry {
+  id: string;
+  timestamp: string;
+  action: string;
+  category: AuditCategory;
+  severity: AuditSeverity;
+  actor: string | null;
+  target: string | null;
+  outcome: AuditOutcome;
+  metadata: Record<string, unknown>;
+  sessionId: string;
+  url: string | null;
+  userAgent: string | null;
+  prevHash: string;
+  hash: string;
+}
+
+export interface RecordAuditOptions {
+  action?: string;
+  category?: AuditCategory;
+  severity?: AuditSeverity;
+  actor?: string | null;
+  target?: string | null;
+  outcome?: AuditOutcome;
+  metadata?: Record<string, unknown>;
+}
+
+export interface AuditQueryOptions {
+  category?: AuditCategory;
+  severity?: AuditSeverity;
+  actor?: string;
+  search?: string;
+  since?: string | number;
+  until?: string | number;
+  limit?: number;
+}
+
+export interface AuditStats {
+  total: number;
+  bySeverity: Partial<Record<AuditSeverity, number>>;
+  byCategory: Partial<Record<AuditCategory, number>>;
+  byOutcome: Record<AuditOutcome, number>;
+}
 
 const STORAGE_KEY = 'audit-log';
 const MAX_RING_SIZE = 1000;
 
 // ─── State ────────────────────────────────────────────────────────────────────
 
-const _ring = [];
+const _ring: AuditEntry[] = [];
 let _lastHash = '0';
 let _sessionId = `${Date.now()}-${Math.random().toString(36).slice(2, 11)}`;
 let _hydrated = false;
-const _subscribers = new Set();
+const _subscribers = new Set<(entry: AuditEntry) => void>();
 
 // ─── Hashing (browser SubtleCrypto with fallback) ─────────────────────────────
 
@@ -74,14 +124,14 @@ const SENSITIVE_FIELD_NAMES = new Set([
   'password', 'passphrase', 'token', 'apiKey', 'authorization',
 ]);
 
-export function redactSensitive(value) {
+export function redactSensitive(value: unknown): unknown {
   if (value == null) return value;
   if (typeof value === 'string') {
     return value.replace(SECRET_KEY_PATTERN, '[REDACTED_SECRET_KEY]');
   }
   if (Array.isArray(value)) return value.map(redactSensitive);
   if (typeof value === 'object') {
-    const out = {};
+    const out: Record<string, unknown> = {};
     for (const [k, v] of Object.entries(value)) {
       if (SENSITIVE_FIELD_NAMES.has(k)) {
         out[k] = '[REDACTED]';
@@ -102,7 +152,7 @@ async function hydrate() {
   try {
     const stored = await getStoredValue(STORAGE_KEY);
     if (Array.isArray(stored) && stored.length) {
-      _ring.push(...stored.slice(-MAX_RING_SIZE));
+      _ring.push(...(stored.slice(-MAX_RING_SIZE) as AuditEntry[]));
       _lastHash = _ring[_ring.length - 1]?.hash ?? '0';
     }
   } catch {
@@ -124,12 +174,12 @@ hydrate();
 
 // ─── Subscriptions ───────────────────────────────────────────────────────────
 
-export function subscribeAudit(handler) {
+export function subscribeAudit(handler: (entry: AuditEntry) => void) {
   _subscribers.add(handler);
   return () => _subscribers.delete(handler);
 }
 
-function notify(entry) {
+function notify(entry: AuditEntry) {
   for (const fn of _subscribers) {
     try { fn(entry); } catch { /* swallow subscriber errors */ }
   }
@@ -147,7 +197,7 @@ export async function recordAudit({
   target = null,
   outcome = 'success',
   metadata = {},
-} = {}) {
+}: RecordAuditOptions = {}): Promise<AuditEntry> {
   if (!action || typeof action !== 'string') {
     throw new Error('audit.record requires a string action');
   }
@@ -162,7 +212,7 @@ export async function recordAudit({
     actor,
     target,
     outcome,
-    metadata: redactSensitive(metadata),
+    metadata: redactSensitive(metadata) as Record<string, unknown>,
     sessionId: _sessionId,
     url: typeof window !== 'undefined' ? window.location.href : null,
     userAgent: typeof navigator !== 'undefined' ? navigator.userAgent : null,
diff --git a/src/utils/chartUtils.js b/src/utils/chartUtils.ts
similarity index 100%
rename from src/utils/chartUtils.js
rename to src/utils/chartUtils.ts
diff --git a/src/utils/collaboration.js b/src/utils/collaboration.ts
similarity index 100%
rename from src/utils/collaboration.js
rename to src/utils/collaboration.ts
diff --git a/src/utils/errorHandler.js b/src/utils/errorHandler.ts
similarity index 100%
rename from src/utils/errorHandler.js
rename to src/utils/errorHandler.ts
diff --git a/src/utils/export.js b/src/utils/export.ts
similarity index 100%
rename from src/utils/export.js
rename to src/utils/export.ts
diff --git a/src/utils/logger.js b/src/utils/logger.ts
similarity index 100%
rename from src/utils/logger.js
rename to src/utils/logger.ts
diff --git a/src/utils/monitoring.js b/src/utils/monitoring.ts
similarity index 100%
rename from src/utils/monitoring.js
rename to src/utils/monitoring.ts
diff --git a/src/utils/offline.js b/src/utils/offline.ts
similarity index 100%
rename from src/utils/offline.js
rename to src/utils/offline.ts
diff --git a/src/utils/preferences.js b/src/utils/preferences.ts
similarity index 100%
rename from src/utils/preferences.js
rename to src/utils/preferences.ts
diff --git a/src/utils/search.js b/src/utils/search.ts
similarity index 100%
rename from src/utils/search.js
rename to src/utils/search.ts
diff --git a/src/utils/searchUtils.js b/src/utils/searchUtils.ts
similarity index 100%
rename from src/utils/searchUtils.js
rename to src/utils/searchUtils.ts
diff --git a/src/utils/security.js b/src/utils/security.ts
similarity index 100%
rename from src/utils/security.js
rename to src/utils/security.ts
diff --git a/src/utils/stateSync.js b/src/utils/stateSync.ts
similarity index 100%
rename from src/utils/stateSync.js
rename to src/utils/stateSync.ts
diff --git a/tsconfig.json b/tsconfig.json
index 69a995da..41f0acd9 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -29,6 +29,7 @@
   "include": [
     "src/**/*.d.ts",
     "src/lib/**/*.ts",
+    "src/utils/**/*.ts",
     "src/hooks/**/*.ts",
     "src/components/**/*.ts",
     "src/components/**/*.tsx",