diff --git a/README.md b/README.md
index 103e57c..f3a1725 100644
--- a/README.md
+++ b/README.md
@@ -268,7 +268,7 @@ site can flip `USAGE_REPORTING_ENABLED=false` and nothing is sent.
 ## The wire format
 
 `POST {baseUrl}/api/metrics` with `Content-Type: application/json`,
-`Authorization: Bearer <key>`, `User-Agent: trace-client-js/0.4.0 (<application>)`
+`Authorization: Bearer <key>`, `User-Agent: trace-client-js/0.4.1 (<application>)`
 and a body of
 
 ```json
diff --git a/package-lock.json b/package-lock.json
index 50e73ee..c2d61f3 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "trace-client-js",
-  "version": "0.4.0",
+  "version": "0.4.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "trace-client-js",
-      "version": "0.4.0",
+      "version": "0.4.1",
       "license": "MIT",
       "devDependencies": {
         "typescript": "^5.6.0"
diff --git a/package.json b/package.json
index 14bb68f..48664f3 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "trace-client-js",
-  "version": "0.4.0",
+  "version": "0.4.1",
   "private": true,
   "description": "One-file usage-reporting client for trace, for Node and edge runtimes (vendor it, bStats-style)",
   "type": "module",
diff --git a/tests/trace-client.test.ts b/tests/trace-client.test.ts
index 0ab0204..d8f8404 100644
--- a/tests/trace-client.test.ts
+++ b/tests/trace-client.test.ts
@@ -714,7 +714,7 @@ describe("API shape", () => {
     assert.equal(await client.flush(50), undefined);
     assert.equal(await client.close(50), undefined);
     assert.equal(TraceClient.disabled().enabled, false);
-    assert.equal(TRACE_CLIENT_VERSION, "0.4.0");
+    assert.equal(TRACE_CLIENT_VERSION, "0.4.1");
   });
 });
 
diff --git a/trace-client.ts b/trace-client.ts
index 2dce8f3..e39c199 100644
--- a/trace-client.ts
+++ b/trace-client.ts
@@ -1,5 +1,5 @@
 /**
- * trace-client 0.4.0 -- https://github.com/Stephenson-Software/trace-client-js
+ * trace-client 0.4.1 -- https://github.com/Stephenson-Software/trace-client-js
  *
  * One call to report that a program was used. Copy this file into a project
  * as is; there is nothing else to add. Zero dependencies and no Node-only
@@ -13,7 +13,7 @@
  * MIT licensed. Keep this header when vendoring so the file can be found again.
  */
 
-export const TRACE_CLIENT_VERSION = "0.4.0";
+export const TRACE_CLIENT_VERSION = "0.4.1";
 
 // Everything added since 0.1.0 hangs off TraceClient (static members) rather
 // than being a new top-level export, so the file's exported values stay