---
title: "Workers, Cloudflare CLI - Wrangler and cf now upload source maps by default: 2026-10-20 | Harbyn"
description: "Workers, Cloudflare CLI - Wrangler and cf now upload source maps by default, announced Oct 20, 2026."
canonical: "https://harbyn.com/changes/cloudflare/2026-10-20-workers-cloudflare-cli-wrangler-and-cf-now-upload-source-maps-by-default"
last-updated: 2026-10-25
---

# Workers, Cloudflare CLI - Wrangler and cf now upload source maps by default

Markdown version of <https://harbyn.com/changes/cloudflare/2026-10-20-workers-cloudflare-cli-wrangler-and-cf-now-upload-source-maps-by-default>.

Behavior change - Cloudflare. low severity. In effect.

From Wrangler 4.150.0, wrangler deploy , wrangler versions upload , and wrangler preview generate and upload source maps by default. You no longer need to set upload\_source\_maps to get stack traces with your original file names and line numbers. cf deploy also uploads source maps by default.

## Facts

| Fact | Value |
| --- | --- |
| Vendor | [Cloudflare](https://harbyn.com/vendors/cloudflare.md) |
| Kind | Behavior change |
| Severity | low |
| Status | In effect |
| Announced | Oct 20, 2026 |
| Added to Harbyn | Oct 25, 2026 |
| Lead time | No dated deadline |
| Vendor page | <https://developers.cloudflare.com/changelog/post/2026-10-20-source-maps-on-by-default/> |
| Review | Reviewed by a person, extracted by a model |

## Find it in your code

```sh
npx harbyn scan
```

This change names no identifier the scanner can match line by line, so the scan tells you whether your repository uses Cloudflare, from its packages and API hosts. Nothing leaves your machine.

## Sources

Where this event comes from: the page we read, when we read it, and the hash of that snapshot.

- <https://developers.cloudflare.com/changelog/rss/workers.xml> (changelog, fetched 2026-10-21 14:31 UTC, sha256 `318f052f0a4384b0ca3f15657ae345f66c5a42b02367d576265e8231cc161aca`)

## Related changes

### More from Cloudflare

- [@cloudflare/shell and Think's createExecuteTool deprecated](https://harbyn.com/changes/cloudflare/2026-10-20-agents-workers-think-agents-now-use-a-cloudflare-computer-workspace-2.md) (Deprecation, effective Oct 20, 2026)
- [Workspace data requires manual migration](https://harbyn.com/changes/cloudflare/2026-10-20-agents-workers-think-agents-now-use-a-cloudflare-computer-workspace-3.md) (Breaking change, effective Oct 20, 2026)
- [Provider packages deprecated](https://harbyn.com/changes/cloudflare/2026-10-21-agents-workers-ai-ai-gateway-createai-replaces-workers-ai-provider-and-ai-ga-2.md) (Deprecation, announced Oct 21, 2026)
- [CLI 1.0.0-beta.16 renames generated commands to kebab-case](https://harbyn.com/changes/cloudflare/2026-10-16-workers-cloudflare-cli-search-cloudflare-documentation-with-the-cloudflare-c-2.md) (Breaking change, announced Oct 16, 2026)

### Changes at other vendors

- [Amazon Selling Partner API: ORDER\_CHANGE notifications add PreFulfillmentStatusChange for Amazon Autos](https://harbyn.com/changes/amazon-sp-api/2026-10-14-sp-api-updates-new-listings-items-api-ivp-values-in-eu5-jp-and-ca-stores-oct-3.md) (effective Oct 28, 2026)
- [BigCommerce: 301 redirects will apply only to storefront channels](https://harbyn.com/changes/bigcommerce/2026-10-07-301-redirects-now-apply-to-storefront-channels-only.md) (effective Nov 10, 2026)
- [GitHub: Secret scanning audit log business field changes to enterprise slug](https://harbyn.com/changes/github/2026-10-20-updates-to-github-secret-scanning-7.md) (effective Nov 12, 2026)
- [Jira / Atlassian Cloud: New IP address ranges in use from January 1, 2027](https://harbyn.com/changes/atlassian-jira/2026-10-16-atlassian-cloud-adds-new-ip-address-ranges.md) (effective Jan 1, 2027)

[All upcoming deadlines](https://harbyn.com/deadlines.md)