diff --git a/src/simulator/src/data/backupCircuit.js b/src/simulator/src/data/backupCircuit.ts
similarity index 58%
rename from src/simulator/src/data/backupCircuit.js
rename to src/simulator/src/data/backupCircuit.ts
index e15f5e444..e1c214001 100644
--- a/src/simulator/src/data/backupCircuit.js
+++ b/src/simulator/src/data/backupCircuit.ts
@@ -1,33 +1,72 @@
 import { projectSavedSet } from './project'
 import { moduleList, updateOrder } from '../metadata'
+import { Scope } from '../types/scope.types'
 
-/* eslint-disable no-param-reassign */
-function extract(obj) {
+interface Saveable {
+    saveObject(): any
+}
+
+interface BackupData {
+    layout: {
+        width: number
+        height: number
+        title_x: number
+        title_y: number
+        titleEnabled: boolean
+    }
+    verilogMetadata: {
+        isVerilogCircuit: boolean
+        isMainCircuit: boolean
+        code: string
+        subCircuitScopeIds: string[]
+    }
+    allNodes: any[]
+    testbenchData: any
+    id: number | string
+    name: string
+    nodes: number[]
+    restrictedCircuitElementsUsed: any[]
+    [key: string]: any 
+}
+
+declare const globalScope: Scope
+
+/**
+ * Extract save object from an object
+ * @param obj - Object with saveObject method
+ * @returns Result of saveObject method
+ */
+function extract(obj: Saveable): any {
     return obj.saveObject()
 }
 
 // Check if there is anything to backup - to be deprecated
 /**
  * Check if backup is available
- * @param {Scope} scope
- * @return {boolean}
+ * @param scope - Circuit scope
+ * @return True if backup is available
  * @category data
  */
-export function checkIfBackup(scope) {
+export function checkIfBackup(scope: Scope): boolean {
     for (let i = 0; i < updateOrder.length; i++) {
         if (scope[updateOrder[i]].length) return true
     }
     return false
 }
 
-export function backUp(scope = globalScope) {
+/**
+ * Creates a backup of the circuit
+ * @param scope - Circuit scope, defaults to globalScope
+ * @returns Backup data object
+ */
+export function backUp(scope: Scope = globalScope): BackupData {
     // Disconnection of subcircuits are needed because these are the connections between nodes
     // in current scope and those in the subcircuit's scope
     for (let i = 0; i < scope.SubCircuit.length; i++) {
         scope.SubCircuit[i].removeConnections()
     }
 
-    var data = {}
+    const data: BackupData = {} as BackupData
 
     // Storing layout
     data.layout = scope.layout
@@ -69,8 +108,14 @@ export function backUp(scope = globalScope) {
     return data
 }
 
-export function scheduleBackup(scope = globalScope) {
-    var backup = JSON.stringify(backUp(scope))
+/**
+ * Schedules a backup of the circuit
+ * @param scope - Circuit scope, defaults to globalScope
+ * @returns Stringified backup
+ */
+export function scheduleBackup(scope: Scope = globalScope): string {
+    const backup = JSON.stringify(backUp(scope))
+
     if (
         scope.backups.length === 0 ||
         scope.backups[scope.backups.length - 1] !== backup
diff --git a/src/simulator/src/types/scope.types.ts b/src/simulator/src/types/scope.types.ts
new file mode 100644
index 000000000..355622df3
--- /dev/null
+++ b/src/simulator/src/types/scope.types.ts
@@ -0,0 +1,42 @@
+import CircuitElement from '../circuitElement'
+import Node from '../node'
+
+export interface SubCircuit {
+    removeConnections(): void
+    makeConnections(): void
+}
+
+export interface Scope {
+    id: number | string
+    name: string
+    root: CircuitElement
+    timeStamp: number
+    backups: string[]
+    history: string[]
+    layout: {
+        width: number
+        height: number
+        title_x: number
+        title_y: number
+        titleEnabled: boolean
+    }
+    verilogMetadata: {
+        isVerilogCircuit: boolean
+        isMainCircuit: boolean
+        code: string
+        subCircuitScopeIds: string[]
+    }
+    restrictedCircuitElementsUsed: any[]
+    CircuitElement: any[]
+    nodes: Node[]
+    allNodes: Node[]
+    SubCircuit: SubCircuit[]
+    testbenchData: any
+    ox: number
+    oy: number
+    scale: number
+    stack: any[]
+    tunnelList?: Record<string, any>
+    pending?: any[]
+    [key: string]: any
+}