diff --git a/packages/core/src/installation/version.ts b/packages/core/src/installation/version.ts
index 25d9cd99aa6c..7412b0b5516b 100644
--- a/packages/core/src/installation/version.ts
+++ b/packages/core/src/installation/version.ts
@@ -1,8 +1,13 @@
 declare global {
   const OPENCODE_VERSION: string
   const OPENCODE_CHANNEL: string
+  const OPENCODE_PLUGIN_VERSION: string
 }
 
 export const InstallationVersion = typeof OPENCODE_VERSION === "string" ? OPENCODE_VERSION : "local"
 export const InstallationChannel = typeof OPENCODE_CHANNEL === "string" ? OPENCODE_CHANNEL : "local"
 export const InstallationLocal = InstallationChannel === "local"
+// Version of @opencode-ai/plugin installed into config directories. Builds whose own version is not
+// published to npm (forks, custom builds) can pin a published one; otherwise it follows the binary.
+export const InstallationPluginVersion =
+  typeof OPENCODE_PLUGIN_VERSION === "string" ? OPENCODE_PLUGIN_VERSION : InstallationVersion
diff --git a/packages/opencode/script/build.ts b/packages/opencode/script/build.ts
index 60a674a4f869..803a945e0e19 100755
--- a/packages/opencode/script/build.ts
+++ b/packages/opencode/script/build.ts
@@ -197,6 +197,9 @@ for (const item of targets) {
       OTUI_TREE_SITTER_WORKER_PATH: bunfsRoot + treeSitterWorkerPath,
       OPENCODE_WORKER_PATH: workerPath,
       OPENCODE_CHANNEL: `'${Script.channel}'`,
+      ...(process.env.OPENCODE_PLUGIN_VERSION
+        ? { OPENCODE_PLUGIN_VERSION: `'${process.env.OPENCODE_PLUGIN_VERSION}'` }
+        : {}),
       OPENCODE_LIBC: item.os === "linux" ? `'${item.abi ?? "glibc"}'` : "",
       ...(item.os === "linux" ? { "process.env.OPENTUI_LIBC": JSON.stringify(item.abi ?? "glibc") } : {}),
     },
diff --git a/packages/opencode/src/config/config.ts b/packages/opencode/src/config/config.ts
index d24ca22d80e4..3a60e9781fe2 100644
--- a/packages/opencode/src/config/config.ts
+++ b/packages/opencode/src/config/config.ts
@@ -11,7 +11,7 @@ import { Flag } from "@opencode-ai/core/flag/flag"
 import { Auth } from "../auth"
 import { Env } from "../env"
 import { applyEdits, modify } from "jsonc-parser"
-import { InstallationLocal, InstallationVersion } from "@opencode-ai/core/installation/version"
+import { InstallationLocal, InstallationPluginVersion } from "@opencode-ai/core/installation/version"
 import { existsSync } from "fs"
 import { Account } from "@/account/account"
 import { isRecord } from "@/util/record"
@@ -454,7 +454,7 @@ const layer = Layer.effect(
               add: [
                 {
                   name: "@opencode-ai/plugin",
-                  version: InstallationLocal ? undefined : InstallationVersion,
+                  version: InstallationLocal ? undefined : InstallationPluginVersion,
                 },
               ],
             })
diff --git a/packages/opencode/src/config/tui.ts b/packages/opencode/src/config/tui.ts
index 8f503751f379..8190be7c42f9 100644
--- a/packages/opencode/src/config/tui.ts
+++ b/packages/opencode/src/config/tui.ts
@@ -16,7 +16,7 @@ import { FSUtil } from "@opencode-ai/core/fs-util"
 import { CurrentWorkingDirectory } from "./tui-cwd"
 import { ConfigPlugin } from "@/config/plugin"
 import { TuiKeybind } from "@opencode-ai/tui/config/keybind"
-import { InstallationLocal, InstallationVersion } from "@opencode-ai/core/installation/version"
+import { InstallationLocal, InstallationPluginVersion } from "@opencode-ai/core/installation/version"
 import { makeRuntime } from "@opencode-ai/core/effect/runtime"
 import { Filesystem } from "@/util/filesystem"
 import { ConfigVariable } from "@/config/variable"
@@ -239,7 +239,7 @@ const layer = Layer.effect(
             add: [
               {
                 name: "@opencode-ai/plugin",
-                version: InstallationLocal ? undefined : InstallationVersion,
+                version: InstallationLocal ? undefined : InstallationPluginVersion,
               },
             ],
           })
diff --git a/packages/opencode/test/installation/installation.test.ts b/packages/opencode/test/installation/installation.test.ts
index 6154d364fa63..37d4c1228b8e 100644
--- a/packages/opencode/test/installation/installation.test.ts
+++ b/packages/opencode/test/installation/installation.test.ts
@@ -7,7 +7,7 @@ import * as TestClock from "effect/testing/TestClock"
 import { HttpClient, HttpClientRequest, HttpClientResponse } from "effect/unstable/http"
 import { ChildProcess, ChildProcessSpawner } from "effect/unstable/process"
 import { Installation } from "../../src/installation"
-import { InstallationVersion } from "@opencode-ai/core/installation/version"
+import { InstallationPluginVersion, InstallationVersion } from "@opencode-ai/core/installation/version"
 import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
 import { testEffect } from "../lib/effect"
 
@@ -94,6 +94,12 @@ describe("installation", () => {
     })
   })
 
+  describe("plugin version", () => {
+    test("follows the binary version when no plugin version is pinned at build time", () => {
+      expect(InstallationPluginVersion).toBe(InstallationVersion)
+    })
+  })
+
   describe("latest", () => {
     const npm = "https://registry.npmjs.org/opencode-ai/latest"
     const choco = "https://community.chocolatey.org/api/v2/Packages"