# Deno v1.39.3 — Release & Upgrade Intelligence
- **Product:** Deno (https://deno.com)
- **Version:** v1.39.3
- **Released:** Jan 12, 2024
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/deno/updates/v1.39.3/

## Executive Summary (TL;DR)
Deno v1.39.3. Source highlight: feat(unstable): fast subset type checking of JSR dependencies (#21873)

## New Features
- feat(unstable): fast subset type checking of JSR dependencies (#21873)

## Improvements
- perf(lsp): use host-owned cache for auto-import completions (#21852)
- perf: skip expanding exclude globs (#21817)

## Bug Fixes
- fix(ci): update copright year for _fs_cp.js (#21803)
- fix(cli): update import map url (#21824)
- fix(compile): preserve granular unstable features (#21827)
- fix(ext): enable prefer-primordials for internal TypeScript (#21813)
- fix(ext/crypto): initial support for p521 in `generateKey` and `importKey`
- fix(ext/node): add WriteStream.isTTY (#21801)