diff --git a/spec-es6/data_dir.spec.ts b/spec-es6/data_dir.spec.ts
new file mode 100644
index 000000000..7d80a2811
--- /dev/null
+++ b/spec-es6/data_dir.spec.ts
@@ -0,0 +1,78 @@
+import { describe, it, execute, expect } from "./mini_test.ts";
+
+import { getPlatformAppDataDir } from "../src/services/data_dir.ts"
+
+
+
+describe("data_dir.ts unit tests", () => {
+
+  describe("#getPlatformAppDataDir", () => {
+
+    type TestCaseGetPlatformAppDataDir = [
+      description: string,
+      fnValue: Parameters<typeof getPlatformAppDataDir>, 
+      expectedValueFn: (val: ReturnType<typeof getPlatformAppDataDir>) => boolean
+    ]
+    const testCases: TestCaseGetPlatformAppDataDir[] = [
+
+      [
+        "w/ unsupported OS it should return 'null'",
+        ["aix", undefined], 
+        (val) => val === null 
+      ],
+
+      [
+        "w/ win32 and no APPDATA set it should return 'null'",
+        ["win32", undefined],
+        (val) => val === null
+      ],
+
+      [
+        "w/ win32 and set APPDATA it should return set 'APPDATA'",
+        ["win32", "AppData"],
+        (val) => val === "AppData"
+      ],
+
+      [
+        "w/ linux it should return '/.local/share'",
+        ["linux", undefined],
+        (val) => val !== null && val.endsWith("/.local/share")
+      ],
+
+      [
+        "w/ linux and wrongly set APPDATA it should ignore APPDATA and return /.local/share",
+        ["linux", "FakeAppData"],
+        (val) => val !== null && val.endsWith("/.local/share")
+      ],
+
+      [
+        "w/ darwin it should return /Library/Application Support",
+        ["darwin", undefined],
+        (val) => val !== null && val.endsWith("/Library/Application Support")
+      ],
+    ];
+
+      testCases.forEach(testCase => {
+        const [testDescription, value, isExpected] = testCase;
+        return it(testDescription, () => {
+          const actual = getPlatformAppDataDir(...value);
+          const result = isExpected(actual);
+          expect(result).toBeTruthy()
+
+        })
+      })
+
+
+  })
+
+  describe("#getTriliumDataDir", () => {
+    // TODO
+  })
+
+  describe("#getDataDirs", () => {
+    // TODO
+  })
+
+});
+
+execute()
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