diff --git a/src/models/params.ts b/src/models/params.ts
index f754757..6d58506 100644
--- a/src/models/params.ts
+++ b/src/models/params.ts
@@ -19,18 +19,18 @@ export interface Params {
 
 export const defaults = {
     taskCategories: {
-        "7e92266f-0a7b-4728-8322-5fe05ff3b929": { 
-            id: "7e92266f-0a7b-4728-8322-5fe05ff3b929", 
+        "RQ15CD3iX1Ey2f9kat7tfLGZmUx9GGc15nS6A7fYtZv76SnS4": { 
+            id: "RQ15CD3iX1Ey2f9kat7tfLGZmUx9GGc15nS6A7fYtZv76SnS4", 
             label: "Développement",
             costPerTimeUnit: 500,
         },
-        "508a0925-a664-4426-8d40-6974156f0f00": { 
-            id: "508a0925-a664-4426-8d40-6974156f0f00", 
+        "QRdGS5Pr5si9SSjU84WAq19cjxQ3rUL71jKh8oHSMZSY4bBH9": { 
+            id: "QRdGS5Pr5si9SSjU84WAq19cjxQ3rUL71jKh8oHSMZSY4bBH9", 
             label: "Conduite de projet",
             costPerTimeUnit: 500,
         },
-        "7aab4d66-072e-4cc8-aae8-b62edd3237a8": { 
-            id: "7aab4d66-072e-4cc8-aae8-b62edd3237a8", 
+        "RPcqFMLdQrgBSomv7Sao7EQSb7on6rtjfDQK5JZNhNSg9DwEo": { 
+            id: "RPcqFMLdQrgBSomv7Sao7EQSb7on6rtjfDQK5JZNhNSg9DwEo", 
             label: "Recette",
             costPerTimeUnit: 500,
         },
diff --git a/src/models/task.ts b/src/models/task.ts
index 76f3020..ef20a24 100644
--- a/src/models/task.ts
+++ b/src/models/task.ts
@@ -1,4 +1,4 @@
-import { uuidV4 } from "../util/uuid"
+import { uuidV4, base58UUID } from "../util/uuid"
 import { defaults } from "./params";
 
 export type TaskID = string
@@ -26,7 +26,7 @@ export interface TaskCategory {
 
 export function newTask(label: string, category: TaskCategoryID): Task {
   return {
-    id: uuidV4(),
+    id: base58UUID(),
     label,
     category,
     estimations: {
@@ -39,7 +39,7 @@ export function newTask(label: string, category: TaskCategoryID): Task {
 
 export function createTaskCategory(): TaskCategory {
   return {
-    id: uuidV4(),
+    id: base58UUID(),
     costPerTimeUnit: defaults.costPerTimeUnit,
     label: ""
   };