diff --git a/studio/apps/web-react/vite/PublishApiHandler.ts b/studio/apps/web-react/vite/PublishApiHandler.ts
index 3c44d61..ae99847 100644
--- a/studio/apps/web-react/vite/PublishApiHandler.ts
+++ b/studio/apps/web-react/vite/PublishApiHandler.ts
@@ -46,7 +46,11 @@ export class PublishApiHandler {
       if (error instanceof Error && /not found/.test(error.message)) {
         return { status: 404, body: { error: error.message } };
       }
-      return { status: 500, body: { error: 'La création de la proposition a échoué.' } };
+      const detail = error instanceof Error ? ` ${error.message}` : '';
+      return {
+        status: 500,
+        body: { error: `La création de la proposition a échoué.${detail}` },
+      };
     }
   }
 
diff --git a/studio/src/infrastructure/git/GitProductionGameDataProposalGateway.ts b/studio/src/infrastructure/git/GitProductionGameDataProposalGateway.ts
index 14bab9c..a1ef94c 100644
--- a/studio/src/infrastructure/git/GitProductionGameDataProposalGateway.ts
+++ b/studio/src/infrastructure/git/GitProductionGameDataProposalGateway.ts
@@ -1,5 +1,5 @@
 import { execFile } from 'node:child_process';
-import { cp, mkdtemp, mkdir, rm, writeFile } from 'node:fs/promises';
+import { cp, mkdtemp, mkdir, readFile, rm, writeFile } from 'node:fs/promises';
 import { tmpdir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { promisify } from 'node:util';
@@ -41,7 +41,7 @@ export class GitProductionGameDataProposalGateway implements ProductionGameDataP
         join(worktreePath, internalCatalogPath),
         { recursive: true },
       );
-      await this.npm(['version', 'patch', '--no-git-tag-version'], worktreePath);
+      await this.bumpPatchVersion(worktreePath);
       await this.git([
         '-C',
         worktreePath,
@@ -78,8 +78,31 @@ export class GitProductionGameDataProposalGateway implements ProductionGameDataP
     await executeFile('git', args, { cwd: this.repositoryPath });
   }
 
-  private async npm(args: readonly string[], cwd: string): Promise<void> {
-    const executable = process.platform === 'win32' ? 'npm.cmd' : 'npm';
-    await executeFile(executable, args, { cwd });
+  private async bumpPatchVersion(worktreePath: string): Promise<void> {
+    const packagePath = join(worktreePath, 'package.json');
+    const lockPath = join(worktreePath, 'package-lock.json');
+    const packageDocument = JSON.parse(await readFile(packagePath, 'utf8')) as {
+      version: string;
+    };
+    const lockDocument = JSON.parse(await readFile(lockPath, 'utf8')) as {
+      version: string;
+      packages: Record<string, { version?: string }>;
+    };
+    const versionParts = packageDocument.version.split('.').map(Number);
+    if (
+      versionParts.length !== 3
+      || versionParts.some((part) => !Number.isInteger(part) || part < 0)
+    ) {
+      throw new Error(`Unsupported package version '${packageDocument.version}'.`);
+    }
+    const nextVersion = `${versionParts[0]}.${versionParts[1]}.${versionParts[2] + 1}`;
+    packageDocument.version = nextVersion;
+    lockDocument.version = nextVersion;
+    lockDocument.packages[''] ??= {};
+    lockDocument.packages[''].version = nextVersion;
+    await Promise.all([
+      writeFile(packagePath, `${JSON.stringify(packageDocument, null, 2)}\n`, 'utf8'),
+      writeFile(lockPath, `${JSON.stringify(lockDocument, null, 2)}\n`, 'utf8'),
+    ]);
   }
 }
diff --git a/studio/store/catalog/commanders.json b/studio/store/catalog/commanders.json
index 64987a5..4efc39a 100644
--- a/studio/store/catalog/commanders.json
+++ b/studio/store/catalog/commanders.json
@@ -34,5 +34,39 @@
       ],
       "freeRecruitThreshold": 20
     }
+  },
+  {
+    "id": "Erwan",
+    "name": "Erwan",
+    "description": "aucune",
+    "icon": "aucune",
+    "baseStats": {
+      "pawnMax": 45,
+      "health": 99,
+      "maxDefenseLevel": 2,
+      "wallVisualSet": "default",
+      "defensePowerPerLevel": 8,
+      "pawnDefinitionIdByColor": {
+        "red": "Aegis-soldier-melee-red",
+        "blue": "Aegis-soldier-melee-blue",
+        "green": "Aegis-soldier-melee-green"
+      },
+      "commanderPawnDefinitionIds": [
+        "commander-1-1"
+      ],
+      "officerPawnDefinitionIds": [
+        "Aegis_officer_1",
+        "Aegis_officer_2",
+        "Aegis_officer_4"
+      ],
+      "movementsPerTurn": 3,
+      "skills": [
+        "free-recruits",
+        "destroy-defense-pawns",
+        "expand-pawn-capacity",
+        "tactical-demolition"
+      ],
+      "freeRecruitThreshold": 20
+    }
   }
 ]