# Deno v1.33.0 — Release & Upgrade Intelligence
- **Product:** Deno (https://deno.com)
- **Version:** v1.33.0
- **Released:** Apr 28, 2023
- **Impact Score:** 7/10
- **Breaking Changes:** Source flagged
- **Canonical Analysis:** https://changelogs.us/deno/updates/v1.33.0/

## Executive Summary (TL;DR)
Deno v1.33.0. Source highlight: BREAKING(unstable): remove "Deno.serve(handler, options)" overload (#18759)

## Breaking Changes & Deprecations
- - BREAKING(unstable): remove "Deno.serve(handler, options)" overload (#18759)

## New Features
- Revert "chore(ext/websocket): Add autobahn|testsuite fuzzingclient (#…
- feat(bench): add `--no-run` flag (#18433)
- feat(cli): don't check permissions for statically analyzable dynamic imports
- feat(cli): flatten deno.json configuaration (#17799)
- feat(ext/ffi): support marking symbols as optional (#18529)
- feat(ext/http): Rework Deno.serve using hyper 1.0-rc3 (#18619)

## Improvements
- perf(ext/http): avoid spread arg deopt in op_http_wait (#18850)
- perf(ext/http): optimize away code based on callback length (#18849)
- perf(ext/http): optimize for zero or one-packet response streams (#18834)
- perf(ext/http): use smi for slab IDs (#18848)
- perf(ext/websocket): various performance improvements (#18862)

## Bug Fixes
- fix(compile): write bytes directly to output file (#18777)
- fix(core): Wrap safe collections' argument of primordials (#18750)
- fix(coverage): exclude test files (#18748)
- fix(dts): `URLPatternComponentResult` groups should have possibly undefined
- fix(ext/node): add crypto.sign|verify methods (#18765)
- fix(ext/node): fix hash.flush (#18818)