Playing with Deno on Windows

This repository gathers Deno code examples coming from various websites and books. It also includes several build scripts (batch files) for experimenting with Deno on a Windows machine.

Ada, Akka, C++, COBOL, Component Pascal, Dafny, Dart, Docker, Erlang, Flix, Go, GraalVM, Haskell, Kafka, Kotlin, LLVM, Modula-2, Node.js, Rust, Scala 3, Spark, Spring, Standard ML, TruffleSqueak, WiX Toolset and Zig are other topics we are continuously monitoring.

☛ Read the interview "I have only one learning technique: projects that I’m working on”" with Ryan Dahl to learn more about the early days of Deno.

Project dependencies

This project depends on two external software for the Microsoft Windows platform:

• Deno 2.5 ¹ (release notes)
• Git 2.51 (release notes)

Optionally one may also install the following software:

• ConEmu 2023 ² (release notes)
• Nmap 7.95 ³ (change log)
• Node.js 25.x LTS (change log)
• Visual Studio Code 1.105 (release notes)

🔎 Git for Windows provides a BASH emulation used to run git from the command line (as well as over 250 Unix commands like awk, diff, file, grep, more, mv, rmdir, sed and wc).

For instance our development environment looks as follows (November 2025) ⁴:

C:\opt\ConEmu\                 ( 26 MB)
C:\opt\deno\                   (105 MB)
C:\opt\Git\                    (394 MB)
C:\opt\nmap\                   ( 29 MB)
C:\opt\node-v25.1.0-win-x64\   ( 99 MB)
C:\opt\VSCode\                 (404 MB)
%USERPROFILE%\.deno\5          (< 1 MB)

☛ Installation policy
When possible we install software from a Zip archive rather than via a Windows installer. In our case we defined C:\opt\ as the installation directory for optional software tools (in reference to the /opt/ directory on Unix).

Directory structure ▴

This project is organized as follows:

bin\
docs\
effect-examples\{README.md, hello-effect}
examples\{README.md}
portela-examples\{README.md, Chapter01}
README.md
QUICKREF.md
RESOURCES.md
TYPESCRIPT.md
setenv.bat

where

• directory bin\ contains utility scripts.
• directory docs\ contains Deno related papers/articles.
• directory effect-examples\ contains Effect code examples grabbed from the project's website.
• directory examples\ contains Deno code examples grabbed from various websites.
• directory portela-examples\ contains Deno code examples from Portela's book Deno Web Development.
• file README.md is the Markdown document for this page.
• file QUICKREF.md is our Deno quick reference.
• file RESOURCES.md gathers Deno related informations.
• file TYPESCRIPT.md gathers TypeScript related informations.
• file setenv.bat is the batch script for setting up our environment.

We also define a virtual drive – e.g. drive O: – in our working environment in order to reduce/hide the real path of our project directory (see article "Windows command prompt limitation" from Microsoft Support).

🔎 We use the Windows external command subst to create virtual drives; for instance:

> subst O: %USERPROFILE%\workspace\deno-examples

Batch commands ▴

setenv.bat

We execute command setenv.bat once to setup our development environment; it makes external tools such as deno.cmd, git.exe, and sh.exe directly available from the command prompt.

> setenv -verbose
Tool versions:
   deno 2.5.6, deployctl 1.12.0, node v25.1.0, ncat 7.95, rustc 1.90.0,
   git 2.51.2, diff 3.12, bash 5.2.37(1)
Tool paths:
   C:\opt\deno\deno.exe
   %USERPROFILE%\.deno\bin\deployctl.cmd
   C:\opt\nmap\ncat.exe
   %USERPROFILE%\.cargo\bin\rustc.exe
   C:\opt\Git\bin\git.exe
   C:\opt\Git\usr\bin\diff.exe
Environment variables:
   "CARGO_HOME=%USERPROFILE%\.cargo"
   "DENO_HOME=C:\opt\deno"
   "GIT_HOME=C:\opt\Git"
   "NMAP_HOME=C:\opt\nmap"
   "NODE_HOME=C:\opt\node-v25.1.0-win-x64"

> where deno git sh
C:\opt\deno\deno.exe
C:\opt\Git\bin\git.exe
C:\opt\Git\mingw64\bin\git.exe
C:\opt\Git\bin\sh.exe
C:\opt\Git\usr\bin\sh.exe

🔎 Subcommand help prints the following help message :

  > setenv help
  Usage: setenv { <option> | <subcommand> }
   
    Options:
      -bash       start Git bash shell instead of Windows command prompt
      -debug      print commands executed by this script
      -verbose    print progress messages
   
    Subcommands:
      help        print this help message
  

Footnotes ▴

[1] Deno TypeScript ↩

Command deno --version displays the supported version of TypeScript, namely version 5.7 in our case:

> deno --version
deno 2.5.5 (stable, release, x86_64-pc-windows-msvc)
v8 14.0.365.5-rusty
typescript 5.9.2

[2] Terminal Programs ↩

Besides the long standing used ConEmu we are now also evaluating Microsoft Windows Terminal (part of MS Windows 11); here is a quick comparison between the two freely available programs :

	ConEmu	Windows Terminal
Last update	July 2023	February 2025
Download size	5 MB	11 MB
Installation size	25 MB	33 MB
Memory usage a)	9 MB	21 MB

^a) Memory usage with 1 command prompt.

[3] Nmap tools ↩

We are mostly interested in the Ncat tool for reading, writing, redirecting, and encrypting data across a network. Ncat operates in one of two modes: in connect mode, Ncat works as a client, in listen mode it is a server,

[4] Downloads ↩

In our case we downloaded the following installation files (see section 1):

ConEmuPack.230724.7z              (  5 MB)
deno-x86_64-pc-windows-msvc.zip   ( 24 MB)
nmap-7.95-setup.zip               ( 28 MB)
node-v25.1.0-win-x64.zip          ( 27 MB)
PortableGit-2.51.2-64-bit.7z.exe  ( 41 MB)
VSCode-win32-x64-1.105.1.zip      (131 MB)

[5] Deployctl ↩

deployctl is the command line tool for Deno Deploy.

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mics/November 2025 ▲