diff --git a/tests/unit/cached.test.ts b/tests/unit/cached.test.ts
new file mode 100644
index 000000000..dcde1a2c9
--- /dev/null
+++ b/tests/unit/cached.test.ts
@@ -0,0 +1,89 @@
+import { describe, expect, test, vi } from "vitest";
+
+import { cached } from "@app/lib/cached";
+
+describe("cached", () => {
+  test("returns the cached result for the same key", async () => {
+    const f = vi.fn(async (x: number) => x * 2);
+    const c = cached(f, x => String(x));
+
+    expect(await c(1)).toBe(2);
+    expect(await c(1)).toBe(2);
+    expect(await c(2)).toBe(4);
+    expect(f).toHaveBeenCalledTimes(2);
+  });
+
+  test("shares a single in-flight request between concurrent callers", async () => {
+    let resolve: ((value: string) => void) | undefined;
+    const f = vi.fn(
+      () =>
+        new Promise<string>(r => {
+          resolve = r;
+        }),
+    );
+    const c = cached(f, () => "key");
+
+    const first = c();
+    const second = c();
+    resolve?.("done");
+
+    expect(await first).toBe("done");
+    expect(await second).toBe("done");
+    expect(f).toHaveBeenCalledTimes(1);
+  });
+
+  test("retries after a rejection", async () => {
+    const f = vi
+      .fn<() => Promise<string>>()
+      .mockRejectedValueOnce(new Error("boom"))
+      .mockResolvedValueOnce("ok");
+    const c = cached(f, () => "key");
+
+    await expect(c()).rejects.toThrow("boom");
+    expect(await c()).toBe("ok");
+    expect(f).toHaveBeenCalledTimes(2);
+  });
+
+  test("clear forces a new request", async () => {
+    const f = vi.fn(async () => "value");
+    const c = cached(f, () => "key");
+
+    await c();
+    c.clear();
+    await c();
+    expect(f).toHaveBeenCalledTimes(2);
+  });
+
+  test("evicts the least recently used entry", async () => {
+    const f = vi.fn(async (x: number) => x);
+    const c = cached(f, x => String(x), { max: 2 });
+
+    await c(1);
+    await c(2);
+    await c(1);
+    await c(3);
+    await c(1);
+    expect(f).toHaveBeenCalledTimes(3);
+    await c(2);
+    expect(f).toHaveBeenCalledTimes(4);
+  });
+
+  test("expires entries after the ttl", async () => {
+    let now = 1000;
+    const f = vi.fn(async () => "value");
+    const c = cached(f, () => "key", {
+      max: 1,
+      ttl: 1000,
+      ttlResolution: 0,
+      perf: { now: () => now },
+    });
+
+    await c();
+    now = 1500;
+    await c();
+    expect(f).toHaveBeenCalledTimes(1);
+    now = 2500;
+    await c();
+    expect(f).toHaveBeenCalledTimes(2);
+  });
+});
diff --git a/tests/unit/markdownFormat.test.ts b/tests/unit/markdownFormat.test.ts
index 9ceaa1782..4b6b92d3d 100644
--- a/tests/unit/markdownFormat.test.ts
+++ b/tests/unit/markdownFormat.test.ts
@@ -32,7 +32,7 @@ describe("bold", () => {
     ["a **|word|** here", "a |word| here"],
     ["a |**word**| here", "a |word| here"],
     ["a **||** here", "a || here"],
-  ])("%p => %p", (input, expected) => {
+  ])("%j => %j", (input, expected) => {
     expect(format(input, "bold")).toBe(expected);
   });
 });
@@ -43,7 +43,7 @@ describe("italic", () => {
     ["a _|word|_ here", "a |word| here"],
     ["a |_word_| here", "a |word| here"],
     ["**|word|**", "**_|word|_**"],
-  ])("%p => %p", (input, expected) => {
+  ])("%j => %j", (input, expected) => {
     expect(format(input, "italic")).toBe(expected);
   });
 });
@@ -56,7 +56,7 @@ describe("code", () => {
     ["```\n|one\ntwo|\n```", "|one\ntwo|"],
     ["a |one\ntwo| b", "a \n```\n|one\ntwo|\n```\n b"],
     ["a\n|one\ntwo|\nb", "a\n```\n|one\ntwo|\n```\nb"],
-  ])("%p => %p", (input, expected) => {
+  ])("%j => %j", (input, expected) => {
     expect(format(input, "code")).toBe(expected);
   });
 });
@@ -66,7 +66,7 @@ describe("link", () => {
     ["see |docs| now", "see [docs](||) now"],
     ["see || now", "see [](||) now"],
     ["see |https://radicle.xyz| now", "see [||](https://radicle.xyz) now"],
-  ])("%p => %p", (input, expected) => {
+  ])("%j => %j", (input, expected) => {
     expect(format(input, "link")).toBe(expected);
   });
 });
@@ -95,7 +95,7 @@ describe("pasteLinkEdit", () => {
       "https://app.radicle.xyz/nodes/iris.radicle.xyz/rad:z4D5U/issues/7bdaa5a",
       "https://app.radicle.xyz/nodes/iris.radicle.xyz/rad:z4D5U/issues/7bdaa5a",
     ],
-  ])("links %p", (pasted, url) => {
+  ])("links %j", (pasted, url) => {
     expect(pasteLinkEdit("docs", 0, 4, pasted)?.text).toBe(`[docs](${url})`);
   });
 
@@ -109,7 +109,7 @@ describe("pasteLinkEdit", () => {
     "just some words",
     "  ",
     "",
-  ])("falls through for %p", pasted => {
+  ])("falls through for %j", pasted => {
     expect(pasteLinkEdit("docs", 0, 4, pasted)).toBeUndefined();
   });
 });
diff --git a/tests/unit/mutexExecutor.test.ts b/tests/unit/mutexExecutor.test.ts
new file mode 100644
index 000000000..b5f159e28
--- /dev/null
+++ b/tests/unit/mutexExecutor.test.ts
@@ -0,0 +1,120 @@
+import { describe, expect, test, vi } from "vitest";
+
+import * as mutexExecutor from "@app/lib/mutexExecutor";
+import { sleep } from "@app/lib/sleep";
+
+describe("executor", () => {
+  test("cancels running task", async () => {
+    const e = mutexExecutor.create();
+
+    const first = e.run(async () => {
+      await sleep(10);
+      return "first";
+    });
+    const second = e.run(async () => {
+      return "second";
+    });
+
+    expect(await first).toBe(undefined);
+    expect(await second).toBe("second");
+
+    const third = e.run(async () => {
+      await sleep(10);
+      return "third";
+    });
+    const fourth = e.run(async () => {
+      return "fourth";
+    });
+
+    expect(await third).toBe(undefined);
+    expect(await fourth).toBe("fourth");
+  });
+
+  test("cancels multiple tasks", async () => {
+    const e = mutexExecutor.create();
+
+    const canceled1 = e.run(async () => {
+      await sleep(10);
+      return true;
+    });
+    const canceled2 = e.run(async () => {
+      await sleep(10);
+      return true;
+    });
+    const canceled3 = e.run(async () => {
+      await sleep(10);
+      return true;
+    });
+    const last = e.run(async () => {
+      return true;
+    });
+
+    expect(await canceled1).toBe(undefined);
+    expect(await canceled2).toBe(undefined);
+    expect(await canceled3).toBe(undefined);
+    expect(await last).toBe(true);
+  });
+
+  test("triggers abort signal event", async () => {
+    const e = mutexExecutor.create();
+    const abortListener = vi.fn();
+
+    void e.run(async abort => {
+      abort.addEventListener("abort", abortListener);
+      await sleep(10);
+      return "first";
+    });
+    expect(abortListener).not.toHaveBeenCalled();
+    // eslint-disable-next-line @typescript-eslint/no-empty-function
+    void e.run(async () => {});
+    expect(abortListener).toHaveBeenCalled();
+  });
+
+  test("don’t throw error on aborted task", async () => {
+    const e = mutexExecutor.create();
+
+    const first = e.run(async () => {
+      await sleep(10);
+      throw new Error();
+    });
+    const second = e.run(async () => {
+      return "second";
+    });
+
+    expect(await first).toBe(undefined);
+    expect(await second).toBe("second");
+  });
+});
+
+describe("worker", () => {
+  test("sequential work", async () => {
+    const w = mutexExecutor.createWorker(async (value: number) => {
+      await sleep(10);
+      return value;
+    });
+
+    const outputs: number[] = [];
+    w.output.onValue(value => outputs.push(value));
+
+    await w.submit(1);
+    await w.submit(2);
+    await w.submit(3);
+
+    expect(outputs).toEqual([1, 2, 3]);
+  });
+
+  test("overlapping work cancels", async () => {
+    const w = mutexExecutor.createWorker(async (value: number) => {
+      await sleep(10);
+      return value;
+    });
+
+    const nextOutput = w.output.firstToPromise();
+
+    void w.submit(1);
+    void w.submit(2);
+    void w.submit(3);
+
+    expect(await nextOutput).toEqual(3);
+  });
+});
diff --git a/tests/unit/repoRouter.test.ts b/tests/unit/repoRouter.test.ts
new file mode 100644
index 000000000..f964e589b
--- /dev/null
+++ b/tests/unit/repoRouter.test.ts
@@ -0,0 +1,155 @@
+import type { RepoRoute } from "@app/views/repo/router";
+
+import { repoRouteToPath, repoUrlToRoute } from "@app/views/repo/router";
+import { describe, expect, test } from "vitest";
+
+const rid = "rad:z3fpY7nttPPa6MBnAv2DccHzQJnqe";
+const peer = "z6MkqGC3nWZhYieEVTVDKW5v588CiGfsDSmRVG9ZwwWTvLSK";
+const sha = "a".repeat(40);
+
+function parse(path: string): RepoRoute | null {
+  const url = new URL(path, "http://localhost");
+  const segments = url.pathname.substring(1).split("/");
+  expect(segments.shift()).toBe("repos");
+  return repoUrlToRoute(segments, url.searchParams);
+}
+
+describe("repoRouteToPath and repoUrlToRoute round trip", () => {
+  test.each<[string, RepoRoute]>([
+    ["/repos/RID/home", { resource: "repo.home", rid }],
+    ["/repos/RID/home/remotes/PEER", { resource: "repo.home", rid, peer }],
+    [
+      "/repos/RID/home/feature/branch",
+      { resource: "repo.home", rid, revision: "feature/branch" },
+    ],
+    [
+      "/repos/RID/home/remotes/PEER/feature/branch",
+      { resource: "repo.home", rid, peer, revision: "feature/branch" },
+    ],
+    ["/repos/RID/commits", { resource: "repo.commits", rid }],
+    [
+      "/repos/RID/commits/main",
+      { resource: "repo.commits", rid, revision: "main" },
+    ],
+    [
+      "/repos/RID/commits/remotes/PEER/SHA",
+      { resource: "repo.commits", rid, peer, revision: sha },
+    ],
+    ["/repos/RID/commits/SHA", { resource: "repo.commit", rid, commit: sha }],
+    ["/repos/RID/identity", { resource: "repo.identity", rid }],
+    [
+      "/repos/RID/issues?status=all",
+      { resource: "repo.issues", rid, status: "all" },
+    ],
+    [
+      "/repos/RID/issues?status=closed",
+      { resource: "repo.issues", rid, status: "closed" },
+    ],
+    [
+      "/repos/RID/issues/abc?status=open",
+      { resource: "repo.issue", rid, issue: "abc", status: "open" },
+    ],
+    [
+      "/repos/RID/patches",
+      { resource: "repo.patches", rid, status: undefined },
+    ],
+    [
+      "/repos/RID/patches?status=merged",
+      { resource: "repo.patches", rid, status: "merged" },
+    ],
+    [
+      "/repos/RID/patches/abc",
+      {
+        resource: "repo.patch",
+        rid,
+        patch: "abc",
+        status: undefined,
+        reviewId: undefined,
+      },
+    ],
+    [
+      "/repos/RID/patches/abc?status=draft&review=def&view=changes",
+      {
+        resource: "repo.patch",
+        rid,
+        patch: "abc",
+        status: "draft",
+        reviewId: "def",
+        view: "changes",
+      },
+    ],
+  ])("%s", (template, route) => {
+    const path = template
+      .replace("RID", rid)
+      .replace("PEER", peer)
+      .replace("SHA", sha);
+
+    expect(repoRouteToPath(route)).toBe(path);
+    expect(parse(path)).toEqual(route);
+  });
+});
+
+describe("repoUrlToRoute", () => {
+  test("defaults issues listing status to all", () => {
+    expect(parse(`/repos/${rid}/issues`)).toEqual({
+      resource: "repo.issues",
+      rid,
+      status: "all",
+    });
+  });
+
+  test("falls back to all for an unknown issues listing status", () => {
+    expect(parse(`/repos/${rid}/issues?status=bogus`)).toEqual({
+      resource: "repo.issues",
+      rid,
+      status: "all",
+    });
+  });
+
+  test("defaults single issue status to all", () => {
+    expect(parse(`/repos/${rid}/issues/abc`)).toEqual({
+      resource: "repo.issue",
+      rid,
+      issue: "abc",
+      status: "all",
+    });
+  });
+
+  test("does not route issue creation", () => {
+    expect(parse(`/repos/${rid}/issues/create`)).toBeNull();
+  });
+
+  test("ignores an unknown patch view", () => {
+    expect(parse(`/repos/${rid}/patches/abc?view=bogus`)).toEqual({
+      resource: "repo.patch",
+      rid,
+      patch: "abc",
+    });
+  });
+
+  test("treats a sha as a revision when a peer is given", () => {
+    expect(parse(`/repos/${rid}/commits/remotes/${peer}/${sha}`)).toEqual({
+      resource: "repo.commits",
+      rid,
+      peer,
+      revision: sha,
+    });
+  });
+
+  test("treats a commits revision that is a sha as a single commit", () => {
+    const route: RepoRoute = { resource: "repo.commits", rid, revision: sha };
+
+    expect(parse(repoRouteToPath(route))).toEqual({
+      resource: "repo.commit",
+      rid,
+      commit: sha,
+    });
+  });
+
+  test.each([`/repos/${rid}`, `/repos/${rid}/bogus`, "/repos/"])(
+    "returns null for %s",
+    path => {
+      expect(parse(path)).toBeNull();
+    },
+  );
+});
diff --git a/tests/unit/utils.test.ts b/tests/unit/utils.test.ts
index cd43a130f..c8996b2dd 100644
--- a/tests/unit/utils.test.ts
+++ b/tests/unit/utils.test.ts
@@ -1,6 +1,26 @@
-import { describe, expect, test } from "vitest";
+import type { Config } from "@bindings/config/Config";
 
-import { coAuthors, safeHttpUrl } from "@app/lib/utils";
+import { describe, expect, test, vi } from "vitest";
+
+import {
+  coAuthors,
+  explorerHost,
+  explorerUrl,
+  formatRepositoryId,
+  formatTimestamp,
+  identityKey,
+  isCommit,
+  parseNodeId,
+  parseRepositoryId,
+  pluralize,
+  revisionPosition,
+  safeHttpUrl,
+  truncateDid,
+  unqualifyBranch,
+} from "@app/lib/utils";
+
+const rid = "rad:z3fpY7nttPPa6MBnAv2DccHzQJnqe";
+const nid = "z6MkqGC3nWZhYieEVTVDKW5v588CiGfsDSmRVG9ZwwWTvLSK";
 
 describe("safeHttpUrl", () => {
   test.each([
@@ -8,7 +28,7 @@ describe("safeHttpUrl", () => {
     ["https://example.com/path?a=1&b=2", "https://example.com/path?a=1&b=2"],
     ["HTTP://EXAMPLE.com/Path", "http://example.com/Path"],
     ["http://example.com/<script>", "http://example.com/%3Cscript%3E"],
-  ])("accepts %p", (input, expected) => {
+  ])("accepts %j", (input, expected) => {
     expect(safeHttpUrl(input)).toBe(expected);
   });
 
@@ -23,7 +43,7 @@ describe("safeHttpUrl", () => {
     "relative",
     "",
     "not a url",
-  ])("rejects %p", input => {
+  ])("rejects %j", input => {
     expect(safeHttpUrl(input)).toBeUndefined();
   });
 });
@@ -80,3 +100,171 @@ describe("coAuthors", () => {
     expect(coAuthors("Subject\n\nJust a body.")).toEqual([]);
   });
 });
+
+describe("parseRepositoryId", () => {
+  test("parses a RID with and without the rad: prefix", () => {
+    expect(parseRepositoryId(rid)).toEqual({
+      prefix: "rad:",
+      pubkey: "z3fpY7nttPPa6MBnAv2DccHzQJnqe",
+    });
+    expect(parseRepositoryId("z3fpY7nttPPa6MBnAv2DccHzQJnqe")).toEqual({
+      prefix: "rad:",
+      pubkey: "z3fpY7nttPPa6MBnAv2DccHzQJnqe",
+    });
+  });
+
+  test.each(["", "rad:", "rad:z3fpY7ntt", `${rid} `, "rad:x3fpY7nttPPa6MBn"])(
+    "rejects %j",
+    input => {
+      expect(parseRepositoryId(input)).toBeUndefined();
+    },
+  );
+});
+
+describe("formatRepositoryId", () => {
+  test("truncates a valid RID", () => {
+    expect(formatRepositoryId(rid)).toBe("rad:z3fpY7…zQJnqe");
+  });
+
+  test("returns an invalid RID unchanged", () => {
+    expect(formatRepositoryId("not-a-rid")).toBe("not-a-rid");
+  });
+});
+
+describe("parseNodeId", () => {
+  test("parses a NID with and without the did:key: prefix", () => {
+    expect(parseNodeId(nid)).toEqual({ prefix: "did:key:", pubkey: nid });
+    expect(parseNodeId(`did:key:${nid}`)).toEqual({
+      prefix: "did:key:",
+      pubkey: nid,
+    });
+  });
+
+  test("rejects a RID", () => {
+    expect(parseNodeId("z3fpY7nttPPa6MBnAv2DccHzQJnqe")).toBeUndefined();
+  });
+
+  test("rejects input that is not base58", () => {
+    vi.spyOn(console, "error").mockReturnValue(undefined);
+    expect(parseNodeId("z0OIl")).toBeUndefined();
+  });
+});
+
+test("truncateDid", () => {
+  expect(truncateDid(`did:key:${nid}`)).toBe("did:key:z6MkqG…WTvLSK");
+});
+
+test.each([
+  ["a".repeat(40), true],
+  ["A".repeat(40), false],
+  ["a".repeat(39), false],
+  ["g".repeat(40), false],
+])("isCommit(%j) is %j", (input, expected) => {
+  expect(isCommit(input)).toBe(expected);
+});
+
+test.each([
+  ["refs/heads/main", "main"],
+  ["refs/heads/feature/x", "feature/x"],
+  ["main", "main"],
+  ["refs/tags/v1", "refs/tags/v1"],
+])("unqualifyBranch(%j) is %j", (input, expected) => {
+  expect(unqualifyBranch(input)).toBe(expected);
+});
+
+describe("formatTimestamp", () => {
+  const now = Date.UTC(2026, 0, 1);
+  const minute = 60 * 1000;
+  const hour = 60 * minute;
+  const day = 24 * hour;
+
+  test.each([
+    [0, "now"],
+    [59 * 1000, "now"],
+    [minute, "1m"],
+    [59 * minute, "59m"],
+    [hour, "1h"],
+    [23 * hour, "23h"],
+    [day, "1d"],
+    [30 * day, "30d"],
+    [31 * day, "1mo"],
+    [364 * day, "11mo"],
+    [365 * day, "1y"],
+    [3 * 365 * day, "3y"],
+  ])("%j ms ago is %j", (elapsed, expected) => {
+    expect(formatTimestamp(now - elapsed, now)).toBe(expected);
+  });
+});
+
+test.each([
+  ["issue", 0, "issues"],
+  ["issue", 1, "issue"],
+  ["issue", 2, "issues"],
+  ["patch", 2, "patches"],
+  ["box", 2, "boxes"],
+  ["class", 2, "classes"],
+])("pluralize(%j, %j) is %j", (singular, count, expected) => {
+  expect(pluralize(singular, count)).toBe(expected);
+});
+
+test("revisionPosition", () => {
+  const revisions = [{ id: "a" }, { id: "b" }, { id: "c" }];
+  expect(revisionPosition(revisions, "a")).toBe(1);
+  expect(revisionPosition(revisions, "c")).toBe(3);
+  expect(revisionPosition(revisions, "x")).toBeUndefined();
+});
+
+describe("identityKey", () => {
+  test("matches identities by email case-insensitively", () => {
+    expect(identityKey({ name: "Alice", email: " Alice@Example.com " })).toBe(
+      identityKey({ name: "A. Lidell", email: "alice@example.com" }),
+    );
+  });
+
+  test("falls back to the name when there is no email", () => {
+    expect(identityKey({ name: "Alice", email: "" })).toBe("name:alice");
+    expect(identityKey({ name: "Alice", email: "" })).not.toBe(
+      identityKey({ name: "Bob", email: "" }),
+    );
+  });
+});
+
+describe("explorer links", () => {
+  function config(overrides: Partial<Config>): Config {
+    return {
+      publicExplorer: "https://radicle.network/nodes/$host/$rid$path",
+      preferredSeeds: [],
+      ...overrides,
+    } as Config;
+  }
+
+  test("uses the first preferred seed host", () => {
+    expect(
+      explorerUrl(
+        `${rid}/issues/abc`,
+        config({
+          preferredSeeds: [
+            `${nid}@seed.example.com:8776`,
+            `${nid}@other.example.com:8776`,
+          ],
+        }),
+      ),
+    ).toBe(`https://radicle.network/nodes/seed.example.com/${rid}/issues/abc`);
+  });
+
+  test("falls back to the default seed", () => {
+    expect(explorerUrl(rid, config({}))).toBe(
+      `https://radicle.network/nodes/rosa.radicle.network/${rid}`,
+    );
+  });
+
+  test("explorerHost returns the host of the template", () => {
+    expect(explorerHost(config({}))).toBe("radicle.network");
+  });
+
+  test("explorerHost returns an unparseable template unchanged", () => {
+    expect(explorerHost(config({ publicExplorer: "not a url" }))).toBe(
+      "not a url",
+    );
+  });
+});