diff --git a/test/js/bun/s3/s3.test.ts b/test/js/bun/s3/s3.test.ts
new file mode 100644
index 00000000000000..4ef031898e1fc2
--- /dev/null
+++ b/test/js/bun/s3/s3.test.ts
@@ -0,0 +1,309 @@
+import { describe, expect, it, beforeAll, afterAll } from "bun:test";
+import { getSecret } from "harness";
+import { randomUUID } from "crypto";
+import { S3, s3, file } from "bun";
+import type { S3File, S3FileOptions } from "bun";
+
+const s3Options: S3FileOptions = {
+  accessKeyId: getSecret("S3_R2_ACCESS_KEY"),
+  secretAccessKey: getSecret("S3_R2_SECRET_KEY"),
+  endpoint: getSecret("S3_R2_ENDPOINT"),
+};
+
+const S3Bucket = getSecret("S3_R2_BUCKET");
+
+describe.skipIf(!s3Options.accessKeyId)("s3", () => {
+  for (let bucketInName of [true, false]) {
+    describe("fetch", () => {
+      describe(bucketInName ? "bucket in path" : "bucket in options", () => {
+        const tmp_filename = bucketInName ? `s3://${S3Bucket}/${randomUUID()}` : `s3://${randomUUID()}`;
+        const options = bucketInName ? s3Options : { ...s3Options, bucket: S3Bucket };
+        beforeAll(async () => {
+          const result = await fetch(tmp_filename, {
+            method: "PUT",
+            body: "Hello Bun!",
+            s3: options,
+          });
+          expect(result.status).toBe(200);
+        });
+
+        afterAll(async () => {
+          const result = await fetch(tmp_filename, {
+            method: "DELETE",
+            s3: options,
+          });
+          expect(result.status).toBe(204);
+        });
+
+        it("should download file via fetch GET", async () => {
+          const result = await fetch(tmp_filename, { s3: options });
+          expect(result.status).toBe(200);
+          expect(await result.text()).toBe("Hello Bun!");
+        });
+
+        it("should download range", async () => {
+          const result = await fetch(tmp_filename, {
+            headers: { "range": "bytes=6-10" },
+            s3: options,
+          });
+          expect(result.status).toBe(206);
+          expect(await result.text()).toBe("Bun!");
+        });
+
+        it("should check if a key exists or content-length", async () => {
+          const result = await fetch(tmp_filename, {
+            method: "HEAD",
+            s3: options,
+          });
+          expect(result.status).toBe(200); // 404 if do not exists
+          expect(result.headers.get("content-length")).toBe("10"); // content-length
+        });
+
+        it("should check if a key does not exist", async () => {
+          const result = await fetch(tmp_filename + "-does-not-exist", { s3: options });
+          expect(result.status).toBe(404);
+        });
+
+        it("should be able to set content-type", async () => {
+          {
+            const result = await fetch(tmp_filename, {
+              method: "PUT",
+              body: "Hello Bun!",
+              headers: {
+                "Content-Type": "application/json",
+              },
+              s3: options,
+            });
+            expect(result.status).toBe(200);
+            const response = await fetch(tmp_filename, { s3: options });
+            expect(response.headers.get("content-type")).toStartWith("application/json");
+          }
+          {
+            const result = await fetch(tmp_filename, {
+              method: "PUT",
+              body: "Hello Bun!",
+              headers: {
+                "Content-Type": "text/plain",
+              },
+              s3: options,
+            });
+            expect(result.status).toBe(200);
+            const response = await fetch(tmp_filename, { s3: options });
+            expect(response.headers.get("content-type")).toStartWith("text/plain");
+          }
+        });
+      });
+    });
+
+    describe("Bun.S3", () => {
+      describe(bucketInName ? "bucket in path" : "bucket in options", () => {
+        const tmp_filename = bucketInName ? `${S3Bucket}/${randomUUID()}` : `${randomUUID()}`;
+        const options = bucketInName ? s3Options : { ...s3Options, bucket: S3Bucket };
+        beforeAll(async () => {
+          const file = new S3(tmp_filename, options);
+          await file.write("Hello Bun!");
+        });
+
+        afterAll(async () => {
+          const file = new S3(tmp_filename, options);
+          await file.unlink();
+        });
+
+        it("should download file via Bun.s3().text()", async () => {
+          const file = new S3(tmp_filename, options);
+          const text = await file.text();
+          expect(text).toBe("Hello Bun!");
+        });
+
+        it("should download range", async () => {
+          const file = new S3(tmp_filename, options);
+          const text = await file.slice(6, 10).text();
+          expect(text).toBe("Bun!");
+        });
+
+        it("should check if a key exists or content-length", async () => {
+          const file = new S3(tmp_filename, options);
+          const exists = await file.exists();
+          expect(exists).toBe(true);
+          const contentLength = await file.size;
+          expect(contentLength).toBe(10);
+        });
+
+        it("should check if a key does not exist", async () => {
+          const file = new S3(tmp_filename + "-does-not-exist", options);
+          const exists = await file.exists();
+          expect(exists).toBe(false);
+        });
+
+        it("should be able to set content-type", async () => {
+          {
+            const s3file = new S3(tmp_filename, { ...options, type: "text/css" });
+            await s3file.write("Hello Bun!");
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("text/css");
+          }
+          {
+            const s3file = new S3(tmp_filename, options);
+            await s3file.write("Hello Bun!", { type: "text/plain" });
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("text/plain");
+          }
+
+          {
+            const s3file = new S3(tmp_filename, options);
+            const writer = s3file.writer({ type: "application/json" });
+            await writer.write("Hello Bun!");
+            await writer.end();
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("application/json");
+          }
+
+          {
+            await S3.upload(tmp_filename, "Hello Bun!", { ...options, type: "application/xml" });
+            const response = await fetch(s3(tmp_filename, options).presign());
+            expect(response.headers.get("content-type")).toStartWith("application/xml");
+          }
+        });
+      });
+    });
+
+    describe("Bun.file", () => {
+      describe(bucketInName ? "bucket in path" : "bucket in options", () => {
+        const tmp_filename = bucketInName ? `s3://${S3Bucket}/${randomUUID()}` : `s3://${randomUUID()}`;
+        const options = bucketInName ? s3Options : { ...s3Options, bucket: S3Bucket };
+        beforeAll(async () => {
+          const s3file = file(tmp_filename, options);
+          await s3file.write("Hello Bun!");
+        });
+
+        afterAll(async () => {
+          const s3file = file(tmp_filename, options);
+          await s3file.unlink();
+        });
+
+        it("should download file via Bun.file().text()", async () => {
+          const s3file = file(tmp_filename, options);
+          const text = await s3file.text();
+          expect(text).toBe("Hello Bun!");
+        });
+
+        it("should download range", async () => {
+          const s3file = file(tmp_filename, options);
+          const text = await s3file.slice(6, 10).text();
+          expect(text).toBe("Bun!");
+        });
+
+        it("should check if a key exists or content-length", async () => {
+          const s3file = file(tmp_filename, options);
+          const exists = await s3file.exists();
+          expect(exists).toBe(true);
+          const contentLength = await s3file.size;
+          expect(contentLength).toBe(10);
+        });
+
+        it("should check if a key does not exist", async () => {
+          const s3file = file(tmp_filename + "-does-not-exist", options);
+          const exists = await s3file.exists();
+          expect(exists).toBe(false);
+        });
+
+        it("should be able to set content-type", async () => {
+          {
+            const s3file = file(tmp_filename, { ...options, type: "text/css" });
+            await s3file.write("Hello Bun!");
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("text/css");
+          }
+          {
+            const s3file = file(tmp_filename, options);
+            await s3file.write("Hello Bun!", { type: "text/plain" });
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("text/plain");
+          }
+
+          {
+            const s3file = file(tmp_filename, options);
+            const writer = s3file.writer({ type: "application/json" });
+            await writer.write("Hello Bun!");
+            await writer.end();
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("application/json");
+          }
+        });
+      });
+    });
+
+    describe("Bun.s3", () => {
+      describe(bucketInName ? "bucket in path" : "bucket in options", () => {
+        const tmp_filename = bucketInName ? `${S3Bucket}/${randomUUID()}` : `${randomUUID()}`;
+        const options = bucketInName ? s3Options : { ...s3Options, bucket: S3Bucket };
+        beforeAll(async () => {
+          const s3file = s3(tmp_filename, options);
+          await s3file.write("Hello Bun!");
+        });
+
+        afterAll(async () => {
+          const s3file = s3(tmp_filename, options);
+          await s3file.unlink();
+        });
+
+        it("should download file via Bun.s3().text()", async () => {
+          const s3file = s3(tmp_filename, options);
+          const text = await s3file.text();
+          expect(text).toBe("Hello Bun!");
+        });
+
+        it("should download range", async () => {
+          const s3file = s3(tmp_filename, options);
+          const text = await s3file.slice(6, 10).text();
+          expect(text).toBe("Bun!");
+        });
+
+        it("should check if a key exists or content-length", async () => {
+          const s3file = s3(tmp_filename, options);
+          const exists = await s3file.exists();
+          expect(exists).toBe(true);
+          const contentLength = await s3file.size;
+          expect(contentLength).toBe(10);
+        });
+
+        it("should check if a key does not exist", async () => {
+          const s3file = s3(tmp_filename + "-does-not-exist", options);
+          const exists = await s3file.exists();
+          expect(exists).toBe(false);
+        });
+
+        it("presign url", async () => {
+          const s3file = s3(tmp_filename, options);
+          const response = await fetch(s3file.presign());
+          expect(response.status).toBe(200);
+          expect(await response.text()).toBe("Hello Bun!");
+        });
+
+        it("should be able to set content-type", async () => {
+          {
+            const s3file = s3(tmp_filename, { ...options, type: "text/css" });
+            await s3file.write("Hello Bun!");
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("text/css");
+          }
+          {
+            const s3file = s3(tmp_filename, options);
+            await s3file.write("Hello Bun!", { type: "text/plain" });
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("text/plain");
+          }
+
+          {
+            const s3file = s3(tmp_filename, options);
+            const writer = s3file.writer({ type: "application/json" });
+            await writer.write("Hello Bun!");
+            await writer.end();
+            const response = await fetch(s3file.presign());
+            expect(response.headers.get("content-type")).toStartWith("application/json");
+          }
+        });
+      });
+    });
+  }
+});