diff --git a/.eslintrc.js b/.eslintrc.js
index db4d77c42..92becc44b 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -3,6 +3,8 @@ module.exports = {
     browser: true,
     jquery: true,
     "jest/globals": true,
+    node: true,
+    es6: true,
   },
   extends: ["eslint:recommended"],
   ignorePatterns: ["**/dist"],
diff --git a/js/packages/binderhub-client/lib/autodetect.js b/js/packages/binderhub-client/lib/autodetect.js
index 6de1d2579..6127f7200 100644
--- a/js/packages/binderhub-client/lib/autodetect.js
+++ b/js/packages/binderhub-client/lib/autodetect.js
@@ -1,10 +1,3 @@
-import { fetch as fetchPolyfill } from "whatwg-fetch";
-
-// Use native browser fetch if available, and use the polyfill if not available
-// (e.g. in tests https://github.com/jestjs/jest/issues/13834#issuecomment-1407375787)
-// @todo: this is only a problem in the jest tests, so get rid of this and mock fetch instead
-const fetch = window.fetch || fetchPolyfill;
-
 /**
  * Dict holding cached values of API request to _config endpoint for base URL
  */
@@ -50,7 +43,7 @@ export async function detect(baseUrl, text) {
         return {
           providerPrefix: provider,
           repository: m.groups.repo,
-          ref: m.groups.ref,
+          ref: m.groups.ref || null,
           path: m.groups.filepath || m.groups.urlpath || null,
           pathType: m.groups.filepath
             ? "filepath"
diff --git a/js/packages/binderhub-client/package.json b/js/packages/binderhub-client/package.json
index 089c12986..b2ab42c3c 100644
--- a/js/packages/binderhub-client/package.json
+++ b/js/packages/binderhub-client/package.json
@@ -14,8 +14,7 @@
   },
   "homepage": "https://github.com/jupyterhub/binderhub#readme",
   "dependencies": {
-    "event-iterator": "^2.0.0",
     "event-source-polyfill": "^1.0.31",
-    "whatwg-fetch": "^3.6.19"
+    "event-iterator": "^2.0.0"
   }
 }
diff --git a/js/packages/binderhub-client/tests/autodetect.test.js b/js/packages/binderhub-client/tests/autodetect.test.js
new file mode 100644
index 000000000..73ca91929
--- /dev/null
+++ b/js/packages/binderhub-client/tests/autodetect.test.js
@@ -0,0 +1,119 @@
+import { getRepoProviders, detect } from "../lib/autodetect";
+import { readFileSync } from "node:fs";
+
+const mybinderConfig = JSON.parse(
+  readFileSync(`${__dirname}/fixtures/repoprovider-config.json`, {
+    encoding: "utf-8",
+  }),
+);
+
+// Mock fetch()
+// https://www.leighhalliday.com/mock-fetch-jest
+global.fetch = jest.fn((url) => {
+  if (url == "https://binder.example.org/_config") {
+    return Promise.resolve({
+      json: () => Promise.resolve(mybinderConfig),
+    });
+  }
+  return Promise.reject(`Unexpected URL ${url}`);
+});
+
+beforeEach(() => {
+  fetch.mockClear();
+});
+
+test("getRepoProviders requests and caches the repo provider configs", async () => {
+  const config = await getRepoProviders("https://binder.example.org");
+  expect(config).toEqual(mybinderConfig);
+
+  await getRepoProviders("https://binder.example.org");
+  expect(fetch).toHaveBeenCalledTimes(1);
+});
+
+test("detect returns null if no provider matches", async () => {
+  const result = await detect(
+    "https://binder.example.org",
+    "https://github.com/binder-examples/conda/pulls",
+  );
+  expect(result).toBeNull();
+});
+
+test("detect parses a repo with no path", async () => {
+  const expected = {
+    providerPrefix: "gh",
+    repository: "binder-examples/conda",
+    ref: null,
+    path: null,
+    pathType: null,
+    providerName: "GitHub",
+  };
+  const result = await detect(
+    "https://binder.example.org",
+    "https://github.com/binder-examples/conda",
+  );
+  expect(result).toEqual(expected);
+});
+
+test("detect parses a repo with a ref but no path", async () => {
+  const expected = {
+    providerPrefix: "gh",
+    repository: "binder-examples/conda",
+    ref: "abc",
+    path: null,
+    pathType: null,
+    providerName: "GitHub",
+  };
+  const result = await detect(
+    "https://binder.example.org",
+    "https://github.com/binder-examples/conda/tree/abc",
+  );
+  expect(result).toEqual(expected);
+});
+
+test("detect parses a repo with a ref and file path", async () => {
+  const expected = {
+    providerPrefix: "gh",
+    repository: "binder-examples/conda",
+    ref: "f00a783",
+    path: "index.ipynb",
+    pathType: "filepath",
+    providerName: "GitHub",
+  };
+  const result = await detect(
+    "https://binder.example.org",
+    "https://github.com/binder-examples/conda/blob/f00a783/index.ipynb",
+  );
+  expect(result).toEqual(expected);
+});
+
+test("detect parses a repo with a ref and directory path", async () => {
+  const expected = {
+    providerPrefix: "gh",
+    repository: "binder-examples/conda",
+    ref: "f00a783",
+    path: ".github/workflows",
+    pathType: "urlpath",
+    providerName: "GitHub",
+  };
+  const result = await detect(
+    "https://binder.example.org",
+    "https://github.com/binder-examples/conda/tree/f00a783/.github/workflows",
+  );
+  expect(result).toEqual(expected);
+});
+
+test("detect checks other repo providers", async () => {
+  const expected = {
+    providerPrefix: "gl",
+    repository: "gitlab-org/gitlab-foss",
+    ref: "v16.4.4",
+    path: "README.md",
+    pathType: "filepath",
+    providerName: "GitLab.com",
+  };
+  const result = await detect(
+    "https://binder.example.org",
+    "https://gitlab.com/gitlab-org/gitlab-foss/-/blob/v16.4.4/README.md",
+  );
+  expect(result).toEqual(expected);
+});
diff --git a/js/packages/binderhub-client/tests/fixtures/repoprovider-config.json b/js/packages/binderhub-client/tests/fixtures/repoprovider-config.json
new file mode 100644
index 000000000..b9cbab818
--- /dev/null
+++ b/js/packages/binderhub-client/tests/fixtures/repoprovider-config.json
@@ -0,0 +1,74 @@
+{
+  "gh": {
+    "text": "GitHub repository name or URL",
+    "tag_text": "Git ref (branch, tag, or commit)",
+    "ref_prop_disabled": false,
+    "label_prop_disabled": false,
+    "display_name": "GitHub",
+    "regex_detect": [
+      "^https://github\\.com/(?<repo>[^/]+/[^/]+)(/blob/(?<ref>[^/]+)(/(?<filepath>.+))?)?$",
+      "^https://github\\.com/(?<repo>[^/]+/[^/]+)(/tree/(?<ref>[^/]+)(/(?<urlpath>.+))?)?$"
+    ]
+  },
+  "gist": {
+    "text": "Gist ID (username/gistId) or URL",
+    "tag_text": "Git commit SHA",
+    "ref_prop_disabled": false,
+    "label_prop_disabled": false,
+    "display_name": "Gist",
+    "regex_detect": [
+      "^https://gist\\.github\\.com/(?<repo>[^/]+/[^/]+)(/(?<ref>[^/]+))?$"
+    ]
+  },
+  "git": {
+    "text": "Arbitrary git repository URL (http://git.example.com/repo)",
+    "tag_text": "Git ref (branch, tag, or commit)",
+    "ref_prop_disabled": false,
+    "label_prop_disabled": false,
+    "display_name": "Git repository",
+    "regex_detect": null
+  },
+  "gl": {
+    "text": "GitLab.com repository or URL",
+    "tag_text": "Git ref (branch, tag, or commit)",
+    "ref_prop_disabled": false,
+    "label_prop_disabled": false,
+    "display_name": "GitLab.com",
+    "regex_detect": [
+      "^https://gitlab\\.com/(?<repo>[^/]+/[^/]+(/[^/-][^/]+)*)(/-/blob/(?<ref>[^/]+)(/(?<filepath>.+))?)?$",
+      "^https://gitlab\\.com/(?<repo>[^/]+/[^/]+(/[^/-][^/]+)*)(/-/tree/(?<ref>[^/]+)(/(?<urlpath>.+))?)?$"
+    ]
+  },
+  "zenodo": {
+    "text": "Zenodo DOI (10.5281/zenodo.3242074)",
+    "tag_text": "Git ref (branch, tag, or commit)",
+    "ref_prop_disabled": true,
+    "label_prop_disabled": true,
+    "display_name": "Zenodo DOI",
+    "regex_detect": null
+  },
+  "figshare": {
+    "text": "Figshare DOI (10.6084/m9.figshare.9782777.v1)",
+    "tag_text": "Git ref (branch, tag, or commit)",
+    "ref_prop_disabled": true,
+    "label_prop_disabled": true,
+    "display_name": "Figshare DOI",
+    "regex_detect": null
+  },
+  "hydroshare": {
+    "text": "Hydroshare resource id or URL",
+    "tag_text": "Git ref (branch, tag, or commit)",
+    "ref_prop_disabled": true,
+    "label_prop_disabled": true,
+    "display_name": "Hydroshare resource",
+    "regex_detect": null
+  },
+  "dataverse": {
+    "text": "Dataverse DOI (10.7910/DVN/TJCLKP)",
+    "tag_text": "Git ref (branch, tag, or commit)",
+    "ref_prop_disabled": true,
+    "label_prop_disabled": true,
+    "display_name": "Dataverse DOI",
+    "regex_detect": null
+  }
+}