Impact Score: 5/10
Deno v0.21.0 — Release Notes & Engineering Impact
Source available — automated, not human-reviewed
Component: deno · Channel: stable. Automated analysis, not a compatibility certification. How this works.
Analysis updated: 2026-11-01.
⚡ Executive Summary (TL;DR)
Deno v0.21.0. Source highlight: feat: --reload flag to take arg for partial reload (#3109)
Who Does This Impact? (Role-Based Analysis)
💻 Software Engineers & Devs
Check the source notes against the package and APIs you use before upgrading.
📊 Product & Engineering Leads
Use the documented changes to assess relevance to your product; release frequency alone is not a quality measure.
⚙️ DevOps & Security
Verify the target version, runtime requirements and rollback procedure in the official documentation.
✨ New Features & Capabilities (3)
- feat: --reload flag to take arg for partial reload (#3109)
- feat: Allow "deno eval" to run code as module (#3148)
- feat: support --allow-net=:4500 (#3115)
⚡ Performance & Enhancements (1)
- perf: eager poll async ops in Isolate (#3046, #3128)
🔧 Bug Fixes & Patches (6)
- fix: Ensure DENO_DIR when saving the REPL history (#3106)
- fix: Update echo_server to new listen API (denoland/deno_std#625)
- fix: [prettier] deno fmt should format jsx/tsx files (#3118)
- fix: [tls] op_dial_tls is not registerd and broken (#3121)
- fix: clearTimer bug (#3143)
- fix: remote jsx/tsx files were compiled as js/ts (#3125)
📄 View Raw Release Notes (Original Developer Log)
### Changes
- feat: --reload flag to take arg for partial reload (#3109)
- feat: Allow "deno eval" to run code as module (#3148)
- feat: support --allow-net=:4500 (#3115)
- fix: Ensure DENO_DIR when saving the REPL history (#3106)
- fix: Update echo_server to new listen API (denoland/deno_std#625)
- fix: [prettier] deno fmt should format jsx/tsx files (#3118)
- fix: [tls] op_dial_tls is not registerd and broken (#3121)
- fix: clearTimer bug (#3143)
- fix: remote jsx/tsx files were compiled as js/ts (#3125)
- perf: eager poll async ops in Isolate (#3046, #3128)
- chore: Move std/fs/path to std/path (#3100)
- upgrade: V8 to 7.9.304 (#3127)
- upgrade: prettier type definition (#3101)
- chore: Add debug build to github actions (#3127)
### Install / Upgrade
**With Shell:**
```sh
curl -fsSL https://deno.land/x/install/install.sh | sh -s v0.21.0
```
**With PowerShell:**
```powershell
iwr https://deno.land/x/install/install.ps1 -useb -outf install.ps1; .\install.ps1 v0.21.0
```