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Running Zig with WASI on Cloudflare Workers

Running Zig with WASI on Cloudflare Workers
Running Zig with WASI on Cloudflare Workers

After the recent announcement regarding WASI support in Workers, I decided to see what it would take to get code written in Zig to run as a Worker, and it turned out to be trivial. This post documents the process I followed as a new user of Zig. It’s so exciting to see how Cloudflare Workers is a polyglot platform allowing you to write programs in the language you love, or the language you’re learning!

Hello, World!

I’m not a Zig expert by any means, and to keep things entirely honest I’ve only just started looking into the language, but we all have to start somewhere. So, if my Zig code isn’t perfect please bear with me. My goal was to build a real, small program using Zig and deploy it on Cloudflare Workers. And to see how fast I can go from a blank screen to production code.

My goal for this wasn’t ambitious, just read some text from stdin and print it to stdout with line numbers, like running cat -n. But it does show just how easy the Workers paradigm is. This Zig program works identically on the command-line on my laptop and as an HTTP Continue reading

Gluware Background And Evolution: Gluware LiveStream June 28, 2022 (7/7) – Video

Gluware focuses on real-world network automation capabilities in brownfield environments. In this video, part of the Packet Pushers LiveStream with Gluware from June 28, 2022, Greg Ferro talks with Gluware’s Ernest Lefner about the product’s capabilities, as well as new features including Network Robotic Process Automation (RPA) and Gluware Topology. For more information, go to […]

The post Gluware Background And Evolution: Gluware LiveStream June 28, 2022 (7/7) – Video appeared first on Packet Pushers.

Tools 11. Running Prometheus Exporters on Dis-aggregated Data Center Switches (Cisco NX-OS, NVIDIA Cumulus Linux, Arista EOS)

Hello my friend,

Monitoring is a key component of any IT and network systems, as it gives us possibility to know what is going on in those systems. That is important at least for two reasons:

  • Observing actual status of the system counters
  • Analyze trends over the time period

Let’s see how we can attempt to normalize collection of such a data with Prometheus from dis-aggregated network switches empowered by Linux.



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What Is the Relation Between Monitoring and Automation?

The answer would be “closed-loop automation” which is also often sold as IBN (Intent-Based Networking). It works as the collected data is automatically compared against certain patterns or thresholds and in case of threshold violation, some automated action can be triggered. It can be as simple as a notification via a mail, a Slack channel or a Telegram chat; however, it can be also a more complicated, where some automated workflow is triggered to perform corrective configuration Continue reading

Linux — Debugging a Python Process with gdb

<MEDIUM: https://raaki-88.medium.com/linux-debugging-a-python-process-with-gdb-b9ea67173aff&gt;

Have you anytime used py-bt inside gdb or used gdb to trace a linux process, if so you can skip this post

GDB is awesome! Am not a everyday programmer but I have been studying internal of linux and operating systems and its fascinating. I wrote about process last time <https://raaki-88.medium.com/linux-process-what-happens-under-the-hood-49e8bcf6173c> and continuing towards threads, Its now making sense when we import modules in python lets examine below snippet which is typically used in Python.

>>> from concurrent.futures import ThreadPoolExecutor

vs

>>> from concurrent.futures import ProcessPoolExecutor

One of the distinctions that I learnt when studying these two functions for multiprocessing is that typical use of ThreadPoolExecutor is when you have IO based activity while ProcessPool is for CPU bound compute activity, I left that

What I now understood is that thread is an integral part of process, there can be multiple threads with in a process and there can be multiple processes, each process needs to be scheduled for CPU cycles and you have different locking mechanism for single process. Now, scheduler algorithm schedules these process as linux is time-sharing based operating system, effectively schedules processes on many factors, Continue reading

Linux — Process, what happens under the hood?

<MEDIUM: https://raaki-88.medium.com/linux-process-what-happens-under-the-hood-49e8bcf6173c&gt;

I have taken operating systems for granted but looking internally it’s an excellent experience to understand how everything gets glued together, this post will be an overview of a process and what happens to a process.

A program is nothing but a set of instructions that the user writes for the desired behavior after execution. when the program gets into a running state that’s when you have a process which gets created and gets associated with the program, in other words, this is how to program is abstracted by the process.

Let’s consider the below python program, we will create some Child processes and Parent processes from the program and see how the underlying operating sees when we execute the program.

You don’t have to be a python expert to know what is going on in this program, basically, we can see the python program has an imported OS module and then it calls on fork() operation to create various child processes.

import os
def child():
    print('\nA new child', os.getpid())
    os._exit(0)

def parent():
    while True:
        newpid = os.fork()
        if newpid == 0:
            child()
        else:
            pids = (os.getpid(), newpid)
            print("Parent: %d,  Continue reading

Controversial Reads 073022


This legislation dutifully provides trial lawyers with endless opportunities to sue Big Tech companies for something indefinable: childhood addiction to websites and phone apps. It puts the state government in charge of defining such addiction.


Recently Google employee Blake Lemoine caused a media storm over the LaMDA chatbot he was working on, that he claims is sentient (it feels things like a human being).


The problem with blockchain is that it’s not an improvement to any system—and often makes things worse.


We stand at a crossroads between a fragmented geopolitical world and a digital one that is more inclusive and sustainable. A common agenda with agreed priorities on public policy issues for the use of technology and connectivity will help take us in the right direction.


Earlier this month, I and others wrote a letter to Congress, basically saying that cryptocurrencies are an complete and total disaster, and urging them to regulate the space.


Of course, this bubble started to deflate when the Federal Reserve started talking about raising interest rates by half a percent. Terra Coin, a “stablecoin,” meaning a crypto that purports to maintain a value tied to an actual currency, collapsed in May.


At this point, they Continue reading

Weekend Reads 072922


Chris Siebenmann has written a short blog piece that reflects on the trend to see Certificate Transparency (CT) as the answer to ‘the problem’; the problem being how to tell if a validly signed and current certificate has somehow had to be repudiated.


For US$2,500, threat actors can employ Matanbuchus, a malware-as-a-service (MaaS) package found delivering Cobalt Strike beacons through phishing and spam messages.


As global and societal events such as supply chain shortages occur, there’s a corresponding increase in fraud related to fake domain registrations (websites) that capitalize on the event—creating unsafe situations for consumers.


Aside from recovery costs and business interruptions — the latter of which can cost as much as USD 22,000 per minute — the most damaging effect of such attacks can be reputational, specifically the loss of customers.


This week, it came to light that gaming platform Roblox was breached via a phishing/social-engineering attack that led to the theft of internal documents and the leaking of them online in an extortion attempt.


Researchers have discovered malware that has been secretly infecting systems featuring Asus and Gigabyte motherboards for at least six years.


The most important point is to understand that there are two very different Continue reading

Heavy Networking 640: Architecture Vs. Engineering Roles

What’s been your experience with architecture vs. engineering roles? Are those distinct functions or combined in your organization? How do the roles interact? Does the architecture team hand down holy designs from their ivory tower the engineering team is expected to implement them? Is the architecture and engineering function more combined, where experienced engineers are expected to create an architecture and help put it in place? Ethan Banks and guest Pat Allen share their experiences with architecture and engineering roles from organizations they've worked in.

The post Heavy Networking 640: Architecture Vs. Engineering Roles appeared first on Packet Pushers.

Heavy Networking 640: Architecture Vs. Engineering Roles

What’s been your experience with architecture vs. engineering roles? Are those distinct functions or combined in your organization? How do the roles interact? Does the architecture team hand down holy designs from their ivory tower the engineering team is expected to implement them? Is the architecture and engineering function more combined, where experienced engineers are expected to create an architecture and help put it in place? Ethan Banks and guest Pat Allen share their experiences with architecture and engineering roles from organizations they've worked in.

Network security depends on two foundations you probably don’t have

You’ve done everything to secure your network, and you still face threats. That’s what most enterprises say about their network security, and they’re half right. Yes, they still face threats, but they’ve not done everything to address them. In fact, most enterprises haven’t really implemented the two foundations on which real network security must be based.When I ask enterprises whether they’ve done a top-down analysis of network security, they usually say they do it every year. When I ask what’s involved in that assessment, they say they look for indications that their current strategies have failed. They build another layer, which is kind of like putting a second Band-Aid on a cut.To read this article in full, please click here

Network security depends on two foundations you probably don’t have

You’ve done everything to secure your network, and you still face threats. That’s what most enterprises say about their network security, and they’re half right. Yes, they still face threats, but they’ve not done everything to address them. In fact, most enterprises haven’t really implemented the two foundations on which real network security must be based.When I ask enterprises whether they’ve done a top-down analysis of network security, they usually say they do it every year. When I ask what’s involved in that assessment, they say they look for indications that their current strategies have failed. They build another layer, which is kind of like putting a second Band-Aid on a cut.To read this article in full, please click here

Network security depends on two foundations you probably don’t have

You’ve done everything to secure your network, and you still face threats. That’s what most enterprises say about their network security, and they’re half right. Yes, they still face threats, but they’ve not done everything to address them. In fact, most enterprises haven’t really implemented the two foundations on which real network security must be based.When I ask enterprises whether they’ve done a top-down analysis of network security, they usually say they do it every year. When I ask what’s involved in that assessment, they say they look for indications that their current strategies have failed. They build another layer, which is kind of like putting a second Band-Aid on a cut.To read this article in full, please click here

Enforcing SLAs with Real Data

I’m sure by now you’ve probably seen tons of articles telling you about how important it is to travel with location devices in your luggage. The most common one I’ve seen is the Apple AirTag. The logic goes that if you have one in your checked suitcase that you’ll know if there are any issues with your luggage getting lost right away because you’ll be notified as soon as you’re separated from it. The advice is sound if you’re someone that checks your bag frequently or has it lost on a regular basis.

The idea behind using technology to enforce an agreement is a great one. We make these agreements all the time, especially in networking. These service level agreements (SLAs) are the way we know we’re getting what we pay for. Take a leased line, for example. You typically pay for a certain speed and a certain amount of availability. The faster the link or the more available it is the more it costs. Any good consumer is going to want to be sure they’re paying for the right service. How can you verify you’re getting what you’re paying for?

For a long time this was very hard to Continue reading

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