Happy Holidays!

I and my team at Browserling wishes everyone warm and happy holidays!

Thanks for reading my blog and see you in 2022!

Cat is the fastest JavaScript bundler

Let's say you have a JavaScript application that has 3 files:


And you need to create bundle.js.

Use cat – no installs, always available on all systems, and works at the speed of a hard drive.

cat ui.js script.js analytics.js > bundle.js

Eat it webpack.

Make ping audible

Sysadmin trick of the day – if a server is down and you don't know when it will be back up, use ping -a to hear when it comes back up. The -a flag enables audio alert.

Announcing onlineLISTtools.com

At Browserling we're building a network of online tools websites. Each site focuses on one and only one tool category. Each tool does one and only one thing.

Today we're releasing a new network site – Online List Tools.

Online List Tools offers a collection of simple, free, and easy-to-use list processing utilities. There are no intrusive ads, popups, or other garbage, just list utilities that work in your browser. Load a list and instantly get the result!


Here's a list of all list tools so far:

Here are the upcoming list tools:

  • Split a List
  • Change List Length
  • Append Items to a List
  • Generate the Powerlist
  • Find the Car of a List
  • Find the Cdr of a List
  • Apply a Function on a List
  • Find Non-repeating List Items
  • Find Repeating List Items
  • Delete Repeating List Items
  • Delete Unique List Items
  • Extract a Sublist from a List
  • Shift List Items
  • Mirror a List
  • Invert a List
  • Reduce a List
  • Convert a List to Rows
  • Convert a List to Excel
  • Convert a List to PDF
  • Convert a Text List to a LaTeX List
  • Convert a Text List to a HTML List
  • Convert a Text List to a Markdown List
  • Zip Two Lists
  • Merge Two Lists
  • Pop List Items
  • Push List Items
  • Replace List Items
  • Splice a List
  • Remove List Item Bullets
  • Remove List Item Counter
  • Create the Empty List
  • Create a Random List
  • Color List Items
  • Visualize a List
  • Let Zalgo Destroy a List

The other websites in the network are:

The next few sites are onlineSETtools, onlineHASHtools, onlineCRYPTOtools, onlineTIMEtools, onlineBITMAPtools, onlinePDFtools, onlineBROWSERtools, onlineAUDIOtools, onlineCSStools, onlineJStools, and a dozen more.

See you next time!

A new user interface for Browserling!

Exciting news at Browserling! My team and I just launched a brand new product interface for Browserling. The new interface lets you access all browsers on all platforms and all features through a single neat menu.

You can try the new user interface right now by following this quick browsing link:


This link will open this same blog post in the latest version of Chrome.

The menu

The new menu contains everything you need to work with Browserling browsers. The top part of the menu focuses on the platform, the browser, and the website that you want to test, and the bottom part lets you quickly access the most popular features.

The features include display options (allows zooming the browser and changing resolutions), screen capture (allows capturing browser screenshots and quickly annotate them), local testing (allows opening an ssh tunnel to localhost or local network to test local websites), on-screen keyboard (allows using an English keyboard on non-English computers, and allows using a keyboard on mobile devices), share a browser (allows sending a quick link to the current browser and website you're viewing), and send feedback (we love feedback!)

Operating system and browser selection

The operating system and browser selection lets you quickly access all available platforms and browsers. With a click or two you quickly load the browser version you need.

URL navigation

The URL navigation field lets you quickly navigate to the website you need. Just enter the address of the website, click the go button, and a browser will open and load the website.

Display options

The display options feature lets you zoom the browser in and out (especially useful if you're on a 4k screen) and change the resolution to a bigger one or a smaller one. Also, this feature lets you do responsive web testing as you can see how your website looks on various screen sizes.

Capture screen

The screen capture feature lets you quickly capture screenshots of your browsing sessions. Once you select the browser region you want to capture, it opens a screenshot of this region and you can use the editing tools, such as a pen, rectangle, text annotation, and eraser tool to make modifications to the screenshot.

I'll be writing another more detailed article about this feature in one of the next posts as it has many other amazing features that let you quickly copy screenshots to clipboard, share bug reports with your co-workers by emailing them, uploading to Imgur, downloading, or saving to your account for later viewing.

Also, coming soon, you'll be able to record your browsing session to a GIF (we call it a GIFcast) or a video.

Local testing

The local testing feature lets you test your local websites that run on the localhost or any local network machine through ssh tunnels. The initial dialog lets you enter the hostname and port of your local web server.

Then, once you run the ssh command and establish a connection between your local computer and our tunneling service, it changes to connected state and you can start testing.

If the connection drops at any time, you'll instantly be notified through a yellow warning message.

I'll be writing another article about local testing as there's a lot to explain.

Onscreen keyboard

The virtual keyboard lets you easily send keypresses to the browser even if you're using a device that doesn't have a physical keyboard, like a tablet. Also, it's very useful if you're using a non-English keyboard, such as German or French keyboards as they have keys for "at" and "slash" symbols in different places.

The keyboard window can be resized to any size, made more compact if you're on a smaller screen or expanded if you're on a bigger screen.

Share a browser

The browser sharing feature lets you quickly share a link to the current platform, browser, and URL that you're viewing with your co-workers and friends.

Also, coming soon, we're launching a collaborative browsing feature that will let you and your team share the same browser.

Send feedback

We love getting feedback, so we also added a quick way to share your thoughts. Let us know what you think about the new UI! My entire team gets all feedback messages.

Technical details

We built our user interface using plain HTML, CSS, JavaScript, and the if logic statement. We started with an empty text file and finished with working code. There are no frameworks, no dependencies, no node modules, no bundlers, and no modern web crap. There's just code that runs the user interface that lets us keep our focus 100% on the product and 0% on resolving node module issues.

What's next?

Next, we're launching a new browser streaming algorithm. The new streaming algorithm will offer near-native experience when using remote browsers. Then, we're adding a collaborative browsing feature that lets two or more people use the same browser at the same time. After this, we're adding a screen recorder that lets you capture your browser sessions to gifs and mp4 videos. And then! More awesome things!

What's Browserling?

Browserling is the world's first online cross-browser testing platform. It offers web developers, web testers, and qa teams quick access to all browsers on all platforms. To make really great web apps and websites, you need to make sure your code and design looks and functions the same on as many platforms, browsers, and screen sizes as possible. You could maintain a bunch of virtual machines and devices or you can simply use Browserling that offers quick cloud access to all the browsers.

Browserling's customers include L'Oreal, T-Mobile, Dolby, Accenture, Payoneer, Wegmans, Library of Congress, House of Representatives, City of New York, State of Texas, UK Home Office, and Government of Australia.

What are other common Browserling use-cases?

Besides being a useful cross-browser testing service, Browserling is also used by security professionals to get a sandboxed browser for testing suspicious links and casual Internet users who want to browse the Internet in an online browser without being tracked.

Thanks everyone for following along my adventure and see you all next time!

Browserling is now used by governments, states, cities, banks, universities, and Forbes 100 companies

Success! I and my team worked super hard and Browserling is now used by everyone – governments, states, cities, banks, stock exchanges, universities, Forbes 100 and Forbes 500 companies, and private multi-billion dollar companies.

I have just updated our customer wall with our most prominent customers.

Browserling is primarily used for cross-browser testing but other use-cases also include browser sandboxing, casual online browsing, and a dozen of custom browser-related solutions.

Thanks everyone for following along my adventure and see you next time!

Announcing onlineGIFtools.com

At Browserling we're building a network of online tools websites. Each site focuses on one and only one tool category. Each tool does one and only one thing.

Today we're releasing the twenty-first network site – Online GIF Tools.

Online GIF Tools offers a collection of simple, free, and easy to use utilities for editing GIF animations. There are no intrusive ads, popups, or other garbage, just GIF utilities that work in your browser. Load a GIF and instantly get the result!


Here's a list of all GIF tools so far:

Here are the upcoming GIF tools:

  • GIF Creator
  • Analyze a GIF
  • Pause a GIF
  • Compress a GIF
  • Rearrange GIF Frames
  • Add Frames to a GIF
  • Randomize a GIF
  • Unzoom a GIF
  • Add GIF Background
  • Remove GIF Background
  • Remove a Border from a GIF
  • Stop GIF Loop
  • Change GIF Loop Count
  • Change GIF Framerate
  • Change GIF Quality
  • Change GIF Brightness
  • Change GIF Contrast
  • Make GIF Faster
  • Make GIF Slower
  • Convert GIF to Base64
  • Convert Base64 to GIF
  • Convert GIF to Base58
  • Convert Base58 to GIF
  • Convert GIF to APNG
  • Convert APNG to GIF
  • Convert GIF to Webp
  • Convert Webp to GIF
  • Convert GIF to PNG
  • Convert PNG to GIF
  • Convert GIF to JPG
  • Convert JPG to GIF
  • Convert GIF to BMP
  • Convert BMP to GIF
  • Convert GIF to BPG
  • Convert BPG to GIF
  • Convert GIF to AVI
  • Convert AVI to GIF
  • Convert GIF to MP4
  • Convert MP4 to GIF
  • Convert GIF to MOV
  • Convert MOV to GIF
  • Convert GIF to GIFV
  • Convert GIFV to GIF
  • Convert GIF to Data URL
  • Convert Data URL to GIF
  • Convert GIF to ASCII Art
  • Convert ASCII Art to GIF
  • Convert GIF to ANSI Art
  • Convert ANSI Art to GIF
  • Convert GIF to Unicode Art
  • Convert Unicode Art to GIF
  • Change Colors in a GIF
  • Convert GIF to Grayscale
  • Make GIF Black and White
  • Extract GIF Colors
  • Extract GIF Color Index
  • Randomize GIF Color Index
  • Reduce GIF Colors
  • Re-quantize GIF Colors
  • Create a True Color GIF
  • Add Dithering to a GIF
  • Remove Dithering From a GIF
  • Optimize a GIF
  • Change Delay of Frames
  • Split a GIF
  • Join GIFs
  • Shift a GIF
  • Sharpen a GIF
  • Hide a Part of a GIF
  • Slice a GIF
  • Duplicate a GIF
  • Duplicate GIF Frames
  • Skew a GIF
  • Add a GIF Frame Counter
  • Add a Timer to GIF
  • Add White Noise to a GIF
  • Generate White Noise GIF
  • Create a Quasistatic GIF
  • Debug a GIF
  • Glitch a GIF

The first twenty websites in the network are:

The next few sites are onlineLISTtools, onlineHASHtools, onlineCRYPTOtools, onlineTIMEtools, onlineBITMAPtools, onlineLINUXtools, onlineBASE64tools, onlinePDFtools, onlineBROWSERtools, onlineAUDIOtools, onlineCSStools, onlineJStools, and a dozen more.

See you next time!

My Favorite Books: Part Eight

This is part eight of my favorite programming, mathematics, physics, and science books.

Quick intro for anyone joining – I've been collecting interesting books for more than 15 years. I'm interested only in books that change thinking and challenge what I already know. I also like fun books that teach you something new in a unique way and books that focus deeply on one topic and one topic only. I hate average books and don't recommend such books. My recommendations have no affiliate links or other garbage. Just awesome books that I truly enjoy.

Previous parts: part one, part two, part three, part four, part five, part six and part seven.

This time, I'm sharing my favorite books about mathematics, history of science, and programming. Here they are!

36. Counterexamples in Analysis

Counterexamples in Analysis.

The best part of mathematics is counterexamples. You can learn things by examples but you'll jump in excitement when you see a counterexample. It will break your understanding of things and teach you something completely new about something you thought you knew. You'll be scratching your head and saying wow. It has happened to me so many times. I was thinking I knew something and then suddenly a punch in the face by a counterexample.

This book contains several hundred elegant counterexamples, most of which you haven't seen or thought about.

  • A nowhere continuous function whose absolute value is everywhere continuous.
  • A function that is everywhere continuous and nowhere differentiable.
  • A continuous function that is nowhere monotonic.
  • A function that is not a derivative.
  • Bounded divergent sequences.
  • Series for which the ratio and root tests fail.
  • Series for which the root test succeeds and the ratio test fails.
  • A discontinuous function of two variables that is continuous in each variable separately.
  • Two monotonic functions whose sum is not monotonic.
  • Two periodic functions whose sum is not periodic.
  • And many more.

I love counterexamples so much. I keep returning to this book. I often open random pages and just try to understand what is happening. Usually, I have no clue as I only know basic calculus but it's still fun.

Here's also a nice quote from the book:

Mathematical questions resolved by a counterexample has the pungency of good drama. Many of the most elegant and artistic contributions to mathematics belong to this genre.

I only know three books that focus a lot on counterexamples. This one, then Quantum Paradoxes that I already mentioned in Part 5, and in one of the next parts, I'll show you one more counterexamples book.

Authors: Bernard R. Gelbaum and John M. H. Olmsted.

37. Ruminations on C++: A Decade of Programming Insight and Experience

Ruminations on C++.

I loved C++ before it became an esoteric Turing tarpit language and this is one of many books that I used to learn programming in C++ (and programming in general). It teaches how to write classic C++ and how to become a successful programmer.

Also, Andrew Koenig is another of my favorite computer scientists and writers. If you've programmed any serious C++, then you'll remember Koenig lookup (also known as argument-dependent lookup or ADL). He's also the author of C Traps and Pitfalls, another of my favorite books.

Author: Andrew Koenig and Barbara Moo.

38. Oliver Heaviside: The Life, Work, and Times of an Electrical Genius of the Victorian Age

Oliver Heaviside.

Amazing book. It takes you through a journey of a scientist you probably haven't heard of. Heaviside invented modern vector calculus and rewrote Maxwell's equations from a very complicated form to modern calculus form. Maxwell had 20 equations and Heaviside simplified them to the 4 elegant equations that we know today. The book has hundreds of pictures and footnotes.

39. Heard on the Street: Quantitative Questions from Wall Street Job Interviews

Heard on the Street.

Math puzzles all the way down. This book contains questions collected from actual job interviews in investment banking, investment management, and options trading. These same questions are nowadays also used in programming interviews. The first part of the book is questions with some hints and tips, and the second part is detailed answers. I can't solve most of them but some day I'd love to.

Author: Timothy F. Crack.

40. The Pragmatic Programmer: From Journeyman to Master

The Pragmatic Programmer.

Another older book that hasn't lost value. It's a joy to read it to remind yourself how to write good code and create successful projects.

Use text files. Learn shell. Write simple code. Use good variable names. Don't repeat yourself. Refactor early and often. Evolve code into what it needs to be. Delight your users.

As I was writing this post, the second edition (20th anniversary edition) was released. Both editions are great and timeless. Get either one.

Author: Andrew Hunt and David Thomas.

Have fun and see you in part nine!

Announcing HwURLs.com

I and my team at Browserling just released HwUrls.com. It's a neat hardware news aggregator that collects news titles from the top 20 hardware blogs and websites and has a super fast search. Check it out!

Other websites in our URLs network are:

  • TuxUrls – linux news aggregator
  • PhysUrls – physics news aggregator
  • MathUrls – mathematics news aggregator
  • FinUrls – finance news aggregator
  • SciUrls – science news aggregator
  • TechUrls – technology news aggregator
  • DevUrls – developer news aggregator

Check them out as well and see you next time!

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