diff --git a/assembly/env/env.ts b/assembly/env/env.ts
index 1d40445a..3181ab2a 100644
--- a/assembly/env/env.ts
+++ b/assembly/env/env.ts
@@ -225,4 +225,28 @@ export namespace env {
 
   @external("massa", "assembly_script_chain_id")
   export declare function chainId(): u64;
+
+  @external("massa", "assembly_script_deferred_call_quote")
+  export declare function deferredCallQuote(
+    ascPeriod: u64,
+    ascThread: u8,
+    maxGas: u64,
+  ): u64;
+
+  @external("massa", "assembly_script_deferred_call_register")
+  export declare function deferredCallRegister(
+    targetAddress: string,
+    targetFunction: string,
+    targetPeriod: u64,
+    targetThread: u8,
+    maxGas: u64,
+    params: StaticArray<u8>,
+    rawCoins: u64,
+  ): string;
+
+  @external("massa", "assembly_script_deferred_call_exists")
+  export declare function deferredCallExists(callId: string): bool;
+
+  @external("massa", "assembly_script_deferred_call_cancel")
+  export declare function deferredCallCancel(callId: string): void;
 }
diff --git a/assembly/std/context.ts b/assembly/std/context.ts
index 19a1444a..ecfa93fe 100644
--- a/assembly/std/context.ts
+++ b/assembly/std/context.ts
@@ -201,3 +201,12 @@ export function currentThread(): u8 {
 export function chainId(): u64 {
   return env.chainId();
 }
+
+export class Slot {
+  public period: u64;
+  public thread: u8;
+  public constructor(period: u64, thread: u8) {
+    this.period = period;
+    this.thread = thread;
+  }
+}
diff --git a/assembly/std/deferredCalls.ts b/assembly/std/deferredCalls.ts
new file mode 100644
index 00000000..8ed3445c
--- /dev/null
+++ b/assembly/std/deferredCalls.ts
@@ -0,0 +1,107 @@
+/**
+ * This module contains all the functions to interact with Massa deferred call (Garanted Autonomous Smart Contracts)
+ */
+
+import { env } from '../env';
+import { Slot } from './context';
+
+/**
+ * Get the price of booking a deferred call in a given slot.
+ *
+ * @param targetSlot - The targeted slot
+ * @param maxGas - The maximum amount of gas that the deferred call can use
+ *
+ * @returns Mas amount
+ *
+ */
+export function deferredCallQuote(targetSlot: Slot, maxGas: u64): u64 {
+  return env.deferredCallQuote(targetSlot.period, targetSlot.thread, maxGas);
+}
+
+/**
+ * Register a new deferred call
+ *
+ * @param targetAddress - The address of the target deferred call
+ * @param targetFunction - The function to call in the target deferred call
+ * @param targetSlot - The target slot for the deferred call
+ * @param maxGas - The maximum amount of gas that the deferred call can use
+ * @param params - The parameters to send to the target deferred call function
+ * @param rawCoins - The amount of coins to send to the target deferred call
+ *
+ * @returns The id of the new deferred call
+ */
+export function deferredCallRegister(
+  targetAddress: string,
+  targetFunction: string,
+  targetSlot: Slot,
+  maxGas: u64,
+  params: StaticArray<u8>,
+  rawCoins: u64,
+): string {
+  return env.deferredCallRegister(
+    targetAddress,
+    targetFunction,
+    targetSlot.period,
+    targetSlot.thread,
+    maxGas,
+    params,
+    rawCoins,
+  );
+}
+
+/**
+ * Check if an deferred call exists
+ *
+ * @param ascCallId - The id of the deferred call
+ *
+ * @returns True if the deferred call exists otherwise false
+ */
+export function deferredCallExists(ascCallId: string): bool {
+  return env.deferredCallExists(ascCallId);
+}
+
+/**
+ * Cancel an deferred call
+ *
+ * @param ascCallId - The id of the deferred call
+ *
+ * @returns True if the deferred call has been canceled otherwise false
+ */
+export function deferredCallCancel(ascCallId: string): void {
+  env.deferredCallCancel(ascCallId);
+}
+
+/**
+ * Find the cheapest slot within a given period range.
+ *
+ * @param startPeriod - The start period of the range to check
+ * @param endPeriod - The end period of the range to check
+ * @param maxGas - The maximum amount of gas that the deferred call can use
+ *
+ * @returns An object containing the period and thread of the cheapest slot
+ */
+export function findCheapestSlot(
+  startPeriod: u64,
+  endPeriod: u64,
+  maxGas: u64,
+): Slot {
+  let cheapestSlotPeriod: u64 = startPeriod;
+  let cheapestSlotThread: u8 = 0;
+  let cheapestSlotPrice: u64 = deferredCallQuote(
+    new Slot(startPeriod, 0),
+    maxGas,
+  );
+
+  for (let period = startPeriod; period <= endPeriod; period++) {
+    for (let thread: u8 = 1; thread < 32; thread++) {
+      const price = deferredCallQuote(new Slot( period, thread ), maxGas);
+      if (price < cheapestSlotPrice) {
+        cheapestSlotPrice = price;
+        cheapestSlotPeriod = period;
+        cheapestSlotThread = thread;
+      }
+    }
+  }
+
+  return new Slot(cheapestSlotPeriod, cheapestSlotThread);
+}
diff --git a/assembly/std/index.ts b/assembly/std/index.ts
index 1e495153..caba1626 100644
--- a/assembly/std/index.ts
+++ b/assembly/std/index.ts
@@ -51,3 +51,8 @@ export * from './context';
  * @module Storage
  */
 export * from './storage';
+
+/**
+ * @module DeferredCalls
+ */
+export * from './deferredCalls';