anomalyco · fromelicks · May 19, 2026 · May 19, 2026 · May 19, 2026 · May 19, 2026
diff --git a/bun.lock b/bun.lock
@@ -54,7 +54,7 @@
     "@dnd-kit/helpers": "0.5.0",
     "@dnd-kit/solid": "0.5.0",
     "@kobalte/core": "catalog:",
-    "@opencode-ai/client": "file:vendor/opencode-ai-client-1.17.13-v2.tgz",
+    "@opencode-ai/client": "file:vendor/opencode-ai-client-1.17.13-prefix.tgz",
     "@opencode-ai/core": "workspace:*",
     "@opencode-ai/schema": "workspace:*",
     "@opencode-ai/sdk": "workspace:*",

@@ -0,0 +1,26 @@
+import { $ } from "bun"
+import { mkdtemp, rm } from "node:fs/promises"
+import { tmpdir } from "node:os"
+import path from "node:path"
+
+// The app consumes a frozen V2 client, not the workspace's current client.
+// Port anomalyco/opencode#47442 without replacing that client's API contract.
+const archive = path.resolve(import.meta.dir, "../vendor/opencode-ai-client-1.17.13-v2.tgz")
+const output = archive.replace("-v2.tgz", "-prefix.tgz")
+const directory = await mkdtemp(path.join(tmpdir(), "opencode-client-prefix-"))
+try {
+  await $`tar -xzf ${archive} -C ${directory}`
+  const file = Bun.file(path.join(directory, "package/dist/promise/generated/client.js"))
+  const source = await file.text()
+  const previous = 'const url = new URL(options.baseUrl.replace(/[/]+$/, "") + descriptor.path);'
+  const patched = `const base = new URL(options.baseUrl);
+        base.pathname = base.pathname.replace(/[/]+$/, "") + "/";
+        const url = new URL(descriptor.path.replace(/^[/]+/, ""), base);`
+  if (!source.includes(patched)) {
+    if (!source.includes(previous)) throw new Error("Vendored client changed: review the prefix patch before repacking")
+    await Bun.write(file, source.replace(previous, patched))
+    await $`tar --sort=name --mtime=@0 --owner=0 --group=0 --numeric-owner -czf ${output} -C ${directory} package`
+  }
+} finally {
+  await rm(directory, { recursive: true, force: true })
+}
@@ -1,3 +1,4 @@
+import { appBasePath } from "./utils/base-path"
 import "@/index.css"
 import * as Sentry from "@sentry/solid"
 import { I18nProvider } from "@opencode-ai/ui/context"
@@ -601,6 +602,7 @@ export function AppInterface(props: {
                     </PermissionProvider>
                   </TabsProvider>
                 )}
+                base={appBasePath() || undefined}
               >
                 <Routes serverScoped={props.serverScoped} />
               </Dynamic>

@@ -1,3 +1,4 @@
+import { appPath } from "@/utils/base-path"
 import { useIsRouting, useLocation } from "@solidjs/router"
 import { batch, createEffect, onCleanup, onMount } from "solid-js"
 import { createStore } from "solid-js/store"
@@ -222,7 +223,7 @@ export function DebugBar(props: { inline?: boolean } = {}) {
 
   createEffect(() => {
     const busy = routing()
-    const next = `${location.pathname}${location.search}`
+    const next = `${appPath(location.pathname)}${location.search}`
 
     if (!init) {
       init = true

@@ -1,3 +1,4 @@
+import { A } from "@solidjs/router"
 import { createEffect, createMemo, createSignal, onCleanup, Show, type Ref } from "solid-js"
 import { createStore } from "solid-js/store"
 import { makeEventListener } from "@solid-primitives/event-listener"
@@ -201,7 +202,7 @@ export function TabNavItem(props: {
       }}
     >
       <MenuV2.Context.Trigger
-        as="a"
+        as={A}
         disabled={editing() || props.dragging}
         aria-haspopup="menu"
         aria-expanded={menu.open}
@@ -381,7 +382,7 @@ export function DraftTabItem(props: {
         closeTab(event)
       }}
     >
-      <a
+      <A
         data-slot="tab-link"
         data-titlebar-tab-link
         href={props.href}
@@ -414,7 +415,7 @@ export function DraftTabItem(props: {
         >
           {props.title}
         </span>
-      </a>
+      </A>
       <div data-slot="tab-close">
         <IconButtonV2
           size="small"

@@ -1,3 +1,4 @@
+import { appPath } from "@/utils/base-path"
 import {
   createEffect,
   createMemo,
@@ -97,13 +98,13 @@ export function Titlebar(props: { update?: TitlebarUpdate; debugTools?: { visibl
     action: undefined as "back" | "forward" | undefined,
   })
 
-  const path = () => `${location.pathname}${location.search}${location.hash}`
+  const path = () => `${appPath(location.pathname)}${location.search}${location.hash}`
   const creating = createMemo(() => {
     const route = layout.route()
     if (route.type === "draft" || route.type === "dir-new-sesssion") return true
     if (!params.dir) return false
     if (params.id) return false
-    const parts = location.pathname.replace(/\/+$/, "").split("/")
+    const parts = appPath(location.pathname).replace(/\/+$/, "").split("/")
     return parts.at(-1) === "session"
   })
 

@@ -1,3 +1,4 @@
+import { appPath } from "@/utils/base-path"
 import { createStore, produce, reconcile } from "solid-js/store"
 import { batch, createEffect, createMemo, onCleanup, onMount, type Accessor } from "solid-js"
 import { useLocation } from "@solidjs/router"
@@ -167,7 +168,7 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
     const platform = usePlatform()
     const location = useLocation()
     const route = createMemo(() => {
-      const value = currentRoute(location.pathname, location.search)
+      const value = currentRoute(appPath(location.pathname), location.search)
       if (value.type === "home") return value
       if (value.server) return value
       if (value.type === "draft") {

@@ -1,3 +1,4 @@
+import { appPath } from "@/utils/base-path"
 import type { Session } from "@opencode-ai/sdk/v2/client"
 import { createSimpleContext } from "@opencode-ai/ui/context"
 import { createStore, produce } from "solid-js/store"
@@ -157,7 +158,7 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
       if (!tab) return
       const key = tabKey(tab)
       const draftID = tab.type === "draft" ? tab.draftID : undefined
-      const nextTab = nextTabAfterClose(store, index, recentKey() === key && location.pathname !== "/")
+      const nextTab = nextTabAfterClose(store, index, recentKey() === key && appPath(location.pathname) !== "/")
       closing.add(key)
       void startTransition(() => {
         setStore(
@@ -231,7 +232,7 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
       promoteDraft(draftID: string, session: Omit<SessionTab, "type">) {
         // Keep the replacement and navigation atomic so /new-session never renders
         // after its backing draft tab has been removed from the store.
-        const active = location.pathname === "/new-session" && location.query.draftId === draftID
+        const active = appPath(location.pathname) === "/new-session" && location.query.draftId === draftID
         const next = { type: "session" as const, ...session }
         void startTransition(() => {
           setStore(

@@ -9,6 +9,7 @@ import { createBrowserDraftStore } from "@/utils/draft-store"
 import { dict as en } from "@/i18n/en"
 import { dict as zh } from "@/i18n/zh"
 import { authFromToken } from "@/utils/server"
+import { appBasePath } from "./utils/base-path"
 import pkg from "../package.json"
 import { ServerConnection } from "./context/server"
 
@@ -97,10 +98,11 @@ if (!(root instanceof HTMLElement) && import.meta.env.DEV) {
 }
 
 const getCurrentUrl = () => {
+  const basePath = appBasePath()
   if (location.hostname.includes("opencode.ai")) return "http://localhost:4096"
   if (import.meta.env.DEV)
-    return `http://${import.meta.env.VITE_OPENCODE_SERVER_HOST ?? "localhost"}:${import.meta.env.VITE_OPENCODE_SERVER_PORT ?? "4096"}`
-  return location.origin
+    return `http://${import.meta.env.VITE_OPENCODE_SERVER_HOST ?? "localhost"}:${import.meta.env.VITE_OPENCODE_SERVER_PORT ?? "4096"}${basePath}`
+  return location.origin + basePath
 }
 
 const getDefaultUrl = () => {

@@ -1,4 +1,5 @@
 interface ImportMetaEnv {
+  readonly BASE_URL: string
   readonly VITE_OPENCODE_SERVER_HOST: string
   readonly VITE_OPENCODE_SERVER_PORT: string
   readonly VITE_OPENCODE_CHANNEL?: "dev" | "beta" | "prod"
@@ -12,6 +13,12 @@ interface ImportMeta {
   readonly env: ImportMetaEnv
 }
 
+declare global {
+  interface Window {
+    __OPENCODE_BASE_PATH__?: string
+  }
+}
+
 declare module "*.png" {
   const src: string
   export default src

@@ -1,3 +1,4 @@
+import { appPath } from "@/utils/base-path"
 import { DataProvider } from "@opencode-ai/session-ui/context"
 import { showToast } from "@/utils/toast"
 import { base64Encode } from "@opencode-ai/core/util/encode"
@@ -38,7 +39,7 @@ export function DirectoryDataProvider(
     if (props.draftID || props.server?.()) return
     const next = sync().data.path.directory
     if (!next || next === directory()) return
-    const path = location.pathname.slice(slug().length + 1)
+    const path = appPath(location.pathname).slice(slug().length + 1)
     navigate(`/${base64Encode(next)}${path}${location.search}${location.hash}`, { replace: true })
   })
 

@@ -1,3 +1,4 @@
+import { appPath } from "@/utils/base-path"
 import type { UserMessage } from "@opencode-ai/sdk/v2"
 import { useLocation, useNavigate } from "@solidjs/router"
 import { createEffect, createMemo, onCleanup, onMount } from "solid-js"
@@ -49,14 +50,14 @@ export const useSessionHashScroll = (input: {
     if (input.pendingMessage()) input.setPendingMessage(undefined)
     if (!location.hash) return
     clearing = true
-    navigate(location.pathname + location.search, { replace: true })
+    navigate(appPath(location.pathname) + location.search, { replace: true })
   }
 
   const updateHash = (id: string) => {
     const hash = `#${input.anchor(id)}`
     if (location.hash === hash) return
     clearing = false
-    navigate(location.pathname + location.search + hash, {
+    navigate(appPath(location.pathname) + location.search + hash, {
       replace: true,
     })
   }

@@ -0,0 +1,52 @@
+import { beforeEach, afterEach, describe, expect, test } from "bun:test"
+import { appBasePath, appPath, serverRequestURL } from "./base-path"
+
+const originalURL = location.href
+beforeEach(() => {
+  location.href = "http://localhost/"
+})
+
+afterEach(() => {
+  delete window.__OPENCODE_BASE_PATH__
+  document.querySelectorAll("base").forEach((base) => base.remove())
+  location.href = originalURL
+})
+
+describe("appBasePath", () => {
+  test("does not confuse a reloaded route with the server prefix", () => {
+    history.replaceState(null, "", "/project/session/test")
+    expect(appBasePath()).toBe("")
+  })
+  test("uses the injected prefix, including an explicitly empty prefix", () => {
+    history.replaceState(null, "", "/apps/opencode/project/session/test")
+    window.__OPENCODE_BASE_PATH__ = "/apps/opencode/"
+    expect(appBasePath()).toBe("/apps/opencode")
+    window.__OPENCODE_BASE_PATH__ = ""
+    expect(appBasePath()).toBe("")
+  })
+  test("supports an explicit same-origin proxy base element", () => {
+    const base = document.createElement("base")
+    base.href = "/nested/proxy/service/"
+    document.head.append(base)
+    expect(appBasePath()).toBe("/nested/proxy/service")
+    base.href = "https://unrelated.example/other/"
+    expect(appBasePath()).toBe("")
+  })
+})
+
+test.each(["", "/", "/proxy", "/proxy/", "/nested/proxy%20path/"])("server URL preserves prefix %j", (prefix) => {
+  expect(serverRequestURL("https://example.com" + prefix, "/api/health?test=a%3Fb").href).toBe(
+    "https://example.com" + prefix.replace(/\/+$/, "") + "/api/health?test=a%3Fb",
+  )
+})
+
+test("application route matching strips exactly one prefix at a segment boundary", () => {
+  window.__OPENCODE_BASE_PATH__ = "/apps/opencode"
+  expect(appPath("/apps/opencode/new-session")).toBe("/new-session")
+  expect(appPath("/apps/opencode/server/test/session/ses_test")).toBe("/server/test/session/ses_test")
+  expect(appPath("/apps/opencode")).toBe("/")
+  expect(appPath("/apps/opencode/")).toBe("/")
+  expect(appPath("/apps/opencode-other/new-session")).toBe("/apps/opencode-other/new-session")
+  window.__OPENCODE_BASE_PATH__ = ""
+  expect(appPath("/new-session")).toBe("/new-session")
+})
@@ -0,0 +1,23 @@
+export function appBasePath() {
+  if (typeof window === "undefined") return ""
+  const injected = window.__OPENCODE_BASE_PATH__
+  if (injected !== undefined) return injected.replace(/\/+$/, "")
+  const base = document.querySelector("base[href]")
+  if (!base) return ""
+  const url = new URL(base.getAttribute("href")!, location.href)
+  return url.origin === location.origin ? url.pathname.replace(/\/+$/, "") : ""
+}
+
+export function serverRequestURL(server: string, path: string) {
+  const base = new URL(server)
+  base.pathname = base.pathname.replace(/\/+$/, "") + "/"
+  return new URL(path.replace(/^\/+/, ""), base)
+}
+
+// Solid Router's location includes its base, while application route parsers do not.
+export function appPath(pathname: string) {
+  const base = appBasePath()
+  if (base && pathname === base) return "/"
+  if (base && pathname.startsWith(base + "/")) return pathname.slice(base.length)
+  return pathname
+}
@@ -38,3 +38,14 @@ describe("detectServerProtocol", () => {
     expect(await detectServerProtocol(server, fetcher)).toBe("v1")
   })
 })
+
+test.each(["/proxy", "/nested/proxy/service/"])("health probes keep the prefix %j", async (prefix) => {
+  const paths: string[] = []
+  const fetcher = mockFetch(async (input) => {
+    const url = new URL(input instanceof Request ? input.url : input)
+    paths.push(url.pathname)
+    return url.pathname.endsWith("/global/health") ? json({}, 404) : json({ healthy: true, pid: 1 })
+  })
+  expect(await detectServerProtocol({ url: "https://example.com" + prefix }, fetcher)).toBe("v2")
+  expect(paths).toEqual([prefix.replace(/\/+$/, "") + "/global/health", prefix.replace(/\/+$/, "") + "/api/health"])
+})
@@ -1,3 +1,4 @@
+import { serverRequestURL } from "./base-path"
 import type { ServerConnection } from "@/context/server"
 import { authTokenFromCredentials } from "./server"
 
@@ -11,7 +12,7 @@ function headers(server: ServerConnection.HttpBase) {
 }
 
 async function probe(server: ServerConnection.HttpBase, fetch: typeof globalThis.fetch, path: string) {
-  const response = await fetch(new URL(path, server.url), {
+  const response = await fetch(serverRequestURL(server.url, path), {
     headers: headers(server),
     signal: AbortSignal.timeout(5_000),
   })