diff --git a/src/event.test.ts b/src/event.test.ts
index e69de29..b0b0462 100644
--- a/src/event.test.ts
+++ b/src/event.test.ts
@@ -0,0 +1,2 @@
+import { test } from "vitest";
+test("placeholder", () => {});
diff --git a/src/filter.test.ts b/src/filter.test.ts
index e69de29..b0b0462 100644
--- a/src/filter.test.ts
+++ b/src/filter.test.ts
@@ -0,0 +1,2 @@
+import { test } from "vitest";
+test("placeholder", () => {});
diff --git a/src/id.test.ts b/src/id.test.ts
index e69de29..b0b0462 100644
--- a/src/id.test.ts
+++ b/src/id.test.ts
@@ -0,0 +1,2 @@
+import { test } from "vitest";
+test("placeholder", () => {});
diff --git a/src/keys.test.ts b/src/keys.test.ts
index e69de29..8d4e39d 100644
--- a/src/keys.test.ts
+++ b/src/keys.test.ts
@@ -0,0 +1,46 @@
+import { describe, test, expect } from "vitest";
+import { Keys } from "./keys";
+import { HEX_64_PATTERN } from "./constants";
+import { testSK, testPK } from "./util.test";
+
+describe("Keys.generatePrivate", () => {
+  test("returns 64 hex characters", () => {
+    const privateKey = Keys.generatePrivate();
+    expect(privateKey).toMatch(HEX_64_PATTERN);
+  });
+
+  test("generates unique keys", () => {
+    const key1 = Keys.generatePrivate();
+    const key2 = Keys.generatePrivate();
+    expect(key1).not.toBe(key2);
+  });
+});
+
+describe("Keys.getPublic", () => {
+  test("derives correct public key", () => {
+    const publicKey = Keys.getPublic(testSK);
+    expect(publicKey).toBe(testPK);
+  });
+
+  test("throws on invalid private key - too short", () => {
+    expect(() => Keys.getPublic("abc123")).toThrow(
+      "private key must be 64 lowercase hex characters",
+    );
+  });
+
+  test("throws on invalid private key - non-hex", () => {
+    expect(() =>
+      Keys.getPublic(
+        "zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz",
+      ),
+    ).toThrow("private key must be 64 lowercase hex characters");
+  });
+
+  test("throws on invalid private key - uppercase", () => {
+    expect(() =>
+      Keys.getPublic(
+        "F43A0435F69529F310BBD1D6263D2FBF0977F54BFE2310CC37AE5904B83BB167",
+      ),
+    ).toThrow("private key must be 64 lowercase hex characters");
+  });
+});
diff --git a/src/keys.ts b/src/keys.ts
index e69de29..be54515 100644
--- a/src/keys.ts
+++ b/src/keys.ts
@@ -0,0 +1,34 @@
+import { schnorr } from "@noble/secp256k1";
+import { HEX_64_PATTERN } from "./constants";
+import { MalformedPrivKeyError } from "./errors";
+
+/**
+ * Generates a new random secp256k1 private key.
+ * @returns 64-character lowercase hexadecimal string
+ */
+function generatePrivate(): string {
+  const { secretKey } = schnorr.keygen();
+  return Buffer.from(secretKey).toString("hex");
+}
+
+/**
+ * Derives the public key from a private key hex string.
+ * @param privateKey - 64-character lowercase hexadecimal private key
+ * @returns 64-character lowercase hexadecimal public key (x-coordinate only)
+ * @throws {MalformedPrivKeyError} If private key is not 64 lowercase hex characters
+ */
+function getPublic(privateKey: string): string {
+  if (!HEX_64_PATTERN.test(privateKey)) {
+    throw new MalformedPrivKeyError();
+  }
+
+  const privateKeyBytes = Buffer.from(privateKey, "hex");
+  const publicKeyBytes = schnorr.getPublicKey(privateKeyBytes);
+
+  return Buffer.from(publicKeyBytes).toString("hex");
+}
+
+export const Keys = {
+  generatePrivate,
+  getPublic,
+};
diff --git a/src/sign.test.ts b/src/sign.test.ts
index e69de29..b0b0462 100644
--- a/src/sign.test.ts
+++ b/src/sign.test.ts
@@ -0,0 +1,2 @@
+import { test } from "vitest";
+test("placeholder", () => {});
diff --git a/src/util.test.ts b/src/util.test.ts
new file mode 100644
index 0000000..2cc7a3a
--- /dev/null
+++ b/src/util.test.ts
@@ -0,0 +1,8 @@
+import { test } from "vitest";
+
+export const testSK =
+  "f43a0435f69529f310bbd1d6263d2fbf0977f54bfe2310cc37ae5904b83bb167";
+export const testPK =
+  "cfa87f35acbde29ba1ab3ee42de527b2cad33ac487e80cf2d6405ea0042c8fef";
+
+test("placeholder", () => {});
diff --git a/src/validate.test.ts b/src/validate.test.ts
index e69de29..b0b0462 100644
--- a/src/validate.test.ts
+++ b/src/validate.test.ts
@@ -0,0 +1,2 @@
+import { test } from "vitest";
+test("placeholder", () => {});