# Deno v1.16.0 — Release & Upgrade Intelligence
- **Product:** Deno (https://deno.com)
- **Version:** v1.16.0
- **Released:** Nov 09, 2021
- **Impact Score:** 7/10
- **Breaking Changes:** Source flagged
- **Canonical Analysis:** https://changelogs.us/deno/updates/v1.16.0/

## Executive Summary (TL;DR)
Deno v1.16.0. Source highlight: BREAKING(ext/web): remove `ReadableStream.getIterator` (#12652)

## Breaking Changes & Deprecations
- - BREAKING(ext/web): remove `ReadableStream.getIterator` (#12652)

## New Features
- feat(cli): support React 17 JSX transforms (#12631)
- feat(compat): add .code to dyn import error (#12633)
- feat(compat): integrate import map and classic resolutions in ESM resolution (#12549)
- feat(ext/console): Display error.cause in console (#12462)
- feat(ext/fetch): support fetching local files (#12545)
- feat(ext/net): add TlsConn.handshake() (#12467)

## Improvements
- perf(core): optimize waker capture in AsyncRefCell (#12332)
- perf(encoding): avoid copying the input data in `TextDecoder` (#12573)
- perf(http): encode string bodies in op-layer (#12451)
- perf: optimize some important crates more aggressively (#12332)

## Bug Fixes
- fix(cli): do not cache emit when diagnostics present (#12541)
- fix(cli): don't panic when mapping unknown errors (#12659)
- fix(cli): lint/format all discoverd files on each change (#12518)
- fix(cli): linter/formater watches current directory without args (#12550)
- fix(cli): no-check respects inlineSources compiler option (#12559)
- fix(cli/upgrade): nice error when unzip is missing (#12693)