diff --git a/package.json b/package.json
index 2ac1671..90f37ec 100644
--- a/package.json
+++ b/package.json
@@ -12,7 +12,7 @@
     "tsc": "headlamp-plugin tsc",
     "storybook": "headlamp-plugin storybook",
     "storybook-build": "headlamp-plugin storybook-build",
-    "test": "headlamp-plugin test",
+    "test": "vitest run -c vitest.config.ts",
     "i18n": "headlamp-plugin i18n"
   },
   "keywords": [
diff --git a/src/__testutils__/kubeObjectMock.ts b/src/__testutils__/kubeObjectMock.ts
new file mode 100644
index 0000000..72ea22f
--- /dev/null
+++ b/src/__testutils__/kubeObjectMock.ts
@@ -0,0 +1,59 @@
+/*
+ * Copyright Contributors to Agones a Series of LF Projects, LLC.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Test-only mock for `@kinvolk/headlamp-plugin/lib/k8s/cluster`.
+ *
+ * Headlamp plugins import `KubeObject` from a path that only resolves at
+ * build time (it's externalized to `pluginLib.K8s.cluster`). This file
+ * provides a minimal stand-in so Vitest can load resource model classes
+ * that extend `KubeObject`.
+ *
+ * Only the subset of KubeObject used by our resource models is implemented:
+ * - `constructor(json)` — stores the raw Kubernetes JSON
+ * - `get metadata()` — delegates to `jsonData.metadata`
+ * - `static useList()` — returns `[null]` (hook stub, not called in unit tests)
+ */
+export class KubeObject<T extends { metadata: any }> {
+  jsonData: T;
+
+  constructor(json: T) {
+    this.jsonData = json;
+  }
+
+  get metadata() {
+    return this.jsonData.metadata;
+  }
+
+  static useList() {
+    return [null];
+  }
+}
+
+export type KubeObjectInterface = {
+  apiVersion: string;
+  kind: string;
+  metadata: {
+    name: string;
+    namespace?: string;
+    uid?: string;
+    creationTimestamp: string;
+    labels?: Record<string, string>;
+    annotations?: Record<string, string>;
+    [key: string]: any;
+  };
+  [key: string]: any;
+};
diff --git a/src/resources/gameserver.test.ts b/src/resources/gameserver.test.ts
new file mode 100644
index 0000000..9b6490f
--- /dev/null
+++ b/src/resources/gameserver.test.ts
@@ -0,0 +1,275 @@
+/*
+ * Copyright Contributors to Agones a Series of LF Projects, LLC.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { describe, expect, it } from 'vitest';
+import { AgonesGameServer, GameServer } from './gameserver';
+
+/**
+ * Helper to create a GameServer instance from a partial JSON object.
+ * Fills in minimal required fields so tests stay focused.
+ */
+function makeGS(overrides: Partial<AgonesGameServer> = {}): GameServer {
+  const base: AgonesGameServer = {
+    apiVersion: 'agones.dev/v1',
+    kind: 'GameServer',
+    metadata: {
+      name: 'test-gs',
+      namespace: 'default',
+      uid: 'abc-123',
+      creationTimestamp: '2026-01-01T00:00:00Z',
+      labels: {},
+      ...(overrides.metadata as any),
+    },
+    spec: {
+      scheduling: 'Packed',
+      template: {},
+      ...(overrides.spec as any),
+    },
+    status: overrides.status,
+  };
+  return new GameServer(base);
+}
+
+describe('GameServer', () => {
+  // ── Static fields ────────────────────────────────────────────────────────
+
+  it('has correct static apiVersion', () => {
+    expect(GameServer.apiVersion).toBe('agones.dev/v1');
+  });
+
+  it('has correct static kind', () => {
+    expect(GameServer.kind).toBe('GameServer');
+  });
+
+  it('has correct static apiName', () => {
+    expect(GameServer.apiName).toBe('gameservers');
+  });
+
+  it('is namespaced', () => {
+    expect(GameServer.isNamespaced).toBe(true);
+  });
+
+  it('has correct detailsRoute', () => {
+    expect(GameServer.detailsRoute).toBe('agones-gameserver');
+  });
+
+  // ── state getter ─────────────────────────────────────────────────────────
+
+  it('returns state from status', () => {
+    const gs = makeGS({ status: { state: 'Ready' } });
+    expect(gs.state).toBe('Ready');
+  });
+
+  it('returns empty string when status is undefined', () => {
+    const gs = makeGS();
+    expect(gs.state).toBe('');
+  });
+
+  it('returns empty string when state is undefined', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.state).toBe('');
+  });
+
+  // ── address getter ───────────────────────────────────────────────────────
+
+  it('returns address from status', () => {
+    const gs = makeGS({ status: { address: '192.168.1.1' } });
+    expect(gs.address).toBe('192.168.1.1');
+  });
+
+  it('returns empty string when address is missing', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.address).toBe('');
+  });
+
+  // ── nodeName getter ──────────────────────────────────────────────────────
+
+  it('returns nodeName from status', () => {
+    const gs = makeGS({ status: { nodeName: 'node-1' } });
+    expect(gs.nodeName).toBe('node-1');
+  });
+
+  it('returns empty string when nodeName is missing', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.nodeName).toBe('');
+  });
+
+  // ── fleet getter ─────────────────────────────────────────────────────────
+
+  it('returns fleet name from labels', () => {
+    const gs = makeGS({
+      metadata: {
+        name: 'test-gs',
+        namespace: 'default',
+        uid: 'abc-123',
+        creationTimestamp: '2026-01-01T00:00:00Z',
+        labels: { 'agones.dev/fleet': 'my-fleet' },
+      } as any,
+    });
+    expect(gs.fleet).toBe('my-fleet');
+  });
+
+  it('returns empty string when fleet label is missing', () => {
+    const gs = makeGS();
+    expect(gs.fleet).toBe('');
+  });
+
+  // ── ports getter ─────────────────────────────────────────────────────────
+
+  it('formats status ports as name:port pairs', () => {
+    const gs = makeGS({
+      status: {
+        ports: [
+          { name: 'game', port: 7777 },
+          { name: 'query', port: 27015 },
+        ],
+      },
+    });
+    expect(gs.ports).toBe('game:7777, query:27015');
+  });
+
+  it('returns empty string when no ports', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.ports).toBe('');
+  });
+
+  // ── counters getter ──────────────────────────────────────────────────────
+
+  it('returns counters from status', () => {
+    const gs = makeGS({
+      status: { counters: { rooms: { count: 3, capacity: 10 } } },
+    });
+    expect(gs.counters).toEqual({ rooms: { count: 3, capacity: 10 } });
+  });
+
+  it('returns empty object when counters missing', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.counters).toEqual({});
+  });
+
+  // ── lists getter ─────────────────────────────────────────────────────────
+
+  it('returns lists from status', () => {
+    const gs = makeGS({
+      status: { lists: { players: { values: ['p1', 'p2'], capacity: 10 } } },
+    });
+    expect(gs.lists).toEqual({ players: { values: ['p1', 'p2'], capacity: 10 } });
+  });
+
+  it('returns empty object when lists missing', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.lists).toEqual({});
+  });
+
+  // ── eviction getter ──────────────────────────────────────────────────────
+
+  it('returns eviction safe mode from spec', () => {
+    const gs = makeGS({
+      spec: { scheduling: 'Packed', template: {}, eviction: { safe: 'Never' } } as any,
+    });
+    expect(gs.eviction).toBe('Never');
+  });
+
+  it('defaults eviction to Never when not set', () => {
+    const gs = makeGS();
+    expect(gs.eviction).toBe('Never');
+  });
+
+  // ── addresses getter ─────────────────────────────────────────────────────
+
+  it('returns addresses from status', () => {
+    const gs = makeGS({
+      status: {
+        addresses: [
+          { type: 'NodeExternalIP', address: '34.56.78.90' },
+          { type: 'NodeInternalIP', address: '10.0.0.5' },
+        ],
+      },
+    });
+    expect(gs.addresses).toEqual([
+      { type: 'NodeExternalIP', address: '34.56.78.90' },
+      { type: 'NodeInternalIP', address: '10.0.0.5' },
+    ]);
+  });
+
+  it('returns empty array when addresses missing', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.addresses).toEqual([]);
+  });
+
+  // ── reservedUntil getter ─────────────────────────────────────────────────
+
+  it('returns reservedUntil from status', () => {
+    const gs = makeGS({
+      status: { reservedUntil: '2026-06-25T12:00:00Z' },
+    });
+    expect(gs.reservedUntil).toBe('2026-06-25T12:00:00Z');
+  });
+
+  it('returns undefined when reservedUntil is not set', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.reservedUntil).toBeUndefined();
+  });
+
+  // ── mergedPorts getter ───────────────────────────────────────────────────
+
+  it('merges spec and status ports', () => {
+    const gs = makeGS({
+      spec: {
+        scheduling: 'Packed',
+        template: {},
+        ports: [{ name: 'game', portPolicy: 'Dynamic', containerPort: 7777, protocol: 'UDP' }],
+      } as any,
+      status: {
+        ports: [{ name: 'game', port: 7654 }],
+      },
+    });
+    expect(gs.mergedPorts).toEqual([
+      {
+        name: 'game',
+        hostPort: 7654,
+        containerPort: 7777,
+        protocol: 'UDP',
+        portPolicy: 'Dynamic',
+      },
+    ]);
+  });
+
+  it('returns empty array when no ports defined', () => {
+    const gs = makeGS({ status: {} });
+    expect(gs.mergedPorts).toEqual([]);
+  });
+
+  it('handles spec ports without matching status ports', () => {
+    const gs = makeGS({
+      spec: {
+        scheduling: 'Packed',
+        template: {},
+        ports: [{ name: 'game', portPolicy: 'Static', containerPort: 7777, protocol: 'TCP' }],
+      } as any,
+      status: { ports: [] },
+    });
+    expect(gs.mergedPorts).toEqual([
+      {
+        name: 'game',
+        hostPort: undefined,
+        containerPort: 7777,
+        protocol: 'TCP',
+        portPolicy: 'Static',
+      },
+    ]);
+  });
+});
diff --git a/vitest.config.ts b/vitest.config.ts
new file mode 100644
index 0000000..92036c7
--- /dev/null
+++ b/vitest.config.ts
@@ -0,0 +1,54 @@
+/*
+ * Copyright Contributors to Agones a Series of LF Projects, LLC.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/// <reference types="vitest" />
+import { defineConfig } from 'vitest/config';
+import { resolve } from 'path';
+
+/**
+ * Vitest configuration for the Agones Headlamp plugin.
+ *
+ * Headlamp plugins import KubeObject from `@kinvolk/headlamp-plugin/lib/k8s/cluster`,
+ * a virtual path that is externalized to `pluginLib.K8s.cluster` at build time.
+ * It doesn't physically exist on disk.
+ *
+ * Vite's import-analysis plugin validates file existence during source
+ * transformation, which fails before Vitest's vi.mock() can intercept.
+ * The resolve alias below redirects that path to a lightweight mock in
+ * `src/__testutils__/kubeObjectMock.ts` that provides just enough of the
+ * KubeObject API for resource model unit tests.
+ *
+ * NOTE: The real `KubeObject` class in headlamp imports React, lodash,
+ * jsonpath-plus, and headlamp's entire API layer — it cannot be loaded
+ * standalone in a test environment without the full headlamp runtime.
+ */
+export default defineConfig({
+  define: {
+    global: 'globalThis',
+  },
+  resolve: {
+    alias: {
+      '@kinvolk/headlamp-plugin/lib/k8s/cluster': resolve(
+        __dirname,
+        'src/__testutils__/kubeObjectMock.ts'
+      ),
+    },
+  },
+  test: {
+    globals: true,
+    environment: 'jsdom',
+  },
+});