diff --git a/CHANGELOG.md b/CHANGELOG.md
index ec9e59601..dccb02aef 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,9 @@
 ### Changes
 - macOS: prompt to install the global `clawdbot` CLI when missing in local mode; install via `clawd.bot/install-cli.sh` (no onboarding) and use external launchd/CLI instead of the embedded gateway runtime.
 
+### Fixes
+- CLI/Update: preserve base environment when passing overrides to update subprocesses. (#713) — thanks @danielz1z.
+
 ## 2026.1.10
 
 ### Highlights
diff --git a/src/process/exec.test.ts b/src/process/exec.test.ts
index 3cb917c3e..b04679989 100644
--- a/src/process/exec.test.ts
+++ b/src/process/exec.test.ts
@@ -19,4 +19,31 @@ describe("runCommandWithTimeout", () => {
     expect(result.code).toBe(0);
     expect(result.stdout).toBe("ok");
   });
+
+  it("merges custom env with process.env", async () => {
+    const previous = process.env.CLAWDBOT_BASE_ENV;
+    process.env.CLAWDBOT_BASE_ENV = "base";
+    try {
+      const result = await runCommandWithTimeout(
+        [
+          process.execPath,
+          "-e",
+          'process.stdout.write((process.env.CLAWDBOT_BASE_ENV ?? "") + "|" + (process.env.CLAWDBOT_TEST_ENV ?? ""))',
+        ],
+        {
+          timeoutMs: 5_000,
+          env: { CLAWDBOT_TEST_ENV: "ok" },
+        },
+      );
+
+      expect(result.code).toBe(0);
+      expect(result.stdout).toBe("base|ok");
+    } finally {
+      if (previous === undefined) {
+        delete process.env.CLAWDBOT_BASE_ENV;
+      } else {
+        process.env.CLAWDBOT_BASE_ENV = previous;
+      }
+    }
+  });
 });