Will Stellar Lumens be the next cryptocurrency star?

The cryptocurrency hype is on. And it does not signal to slow down anytime soon. While Bitcoin is the first and by far the most popular digital currency the landscape in 2021 offers a lot more.

In this post I am comparing Bitcoins (BTC) with Stellar Lumens (XLM), the native digital currency of the Stellar protocol. Stellar’s mission is to setup an open and distributed digital payment infrastructure that can scale globally, supporting various currencies and avoiding high unnecessary fees.

Screenshot from Stellar Beat Dashboard (Stellar network visibility)
Screenshot from Stellar Beat Dashboard (Stellar network visibility)
Screenshot from stellarbeat.io

The Concept

Bitcoin in 2009 was “forged” without any other model to compare to. The initial view was to offer a secure…


Options to overcome the Heroku ephemeral filesystem. For free.

The Challenge

Heroku file system is ephemeral: applications can write on the file system but any change is discarded when the Dyno (the application host) restarts, making this option only suitable for temporary data.

It is also important to remember that Heroku implements cycling: every Dyno reboots (at least) every 24 hours and all local filesystem modifications are deleted.

A solution

Applications that must persist data should instead rely on an external database or a remote file server. …


Build Intel64-compatible Docker images from Mac M1

Docker Desktop (natively) and Heroku CLI (with Rosetta) work nicely on the Apple M1 processor, however, a locally built Docker image will not successfully deploy onto the Heroku Docker Registry.

In a previous article Deploy to Heroku From a MacBook M1: Heroku CLI or GitHubActions, I have described how it is possible (and very convenient) to build a Docker image and deploy it to Heroku using GitHub Actions. Here I am going to look at how to, in a Mac development environment, build and release an image that is compatible with the Heroku Docker Registry runtime.

Image by author

What is happening?

Building and deploying Docker…


Discover advanced features that can make a difference

Telegram is a popular platform to develop chatbots: excellent documentation, vibrant community, various libraries and tons of examples.

If you are getting started there are plenty of tutorials around, especially on Medium. And Stackoverflow is also a great resource for answering questions and understanding issues (your author is often spotted there to try helping fellow developers out 🤓).

This article instead focusses on more advanced aspects related to the implementation of a Telegram bot using Python Telegram Bot:

  • Pull vs Webhook
  • Grab the chat ID
  • Display “Typing…” and suggest answers
  • Deep linking
  • Send media and files
User chatting on Telegram
User chatting on Telegram
Photo by Christian Wiediger on Unsplash

Polling mode to work locally

Telegram Bot can work…


Setting up a new laptop is always fun, but this time with my new flashy MacBook Pro and the Apple-designed M1 chip is a different experience. The device is simply amazing and very performing, however, it has created headaches especially for developers who need to run a variety of tools that are not yet compatible with ARM architecture.

This post is about how to deploy (*) on Heroku your projects developed on the Apple Silicon M1:

  • using Heroku Command Line Interface (with Rosetta)
  • creating a GitHubActions pipeline

(*) note that deploying with git (git push heroku master) works fine (Git…


Direct Messages have been available for a while in Twitter. This is not a surprise as messaging has undoubtedly a huge impact in the way we communicate, work and connect every day.

On Social Platforms messaging can play a pivotal role for businesses which want to extend their reach (increase followers), create a unique brand or deliver ‘not-less-than-excellence’ through their customer experience and support.

Photo by Oleg Magni on Unsplash

Here 1) I will discuss few facts and considerations on how Direct Private Messages can deliver value to a brand or an organisation, 2) I will dive into some technical examples (for the techies 🤓 out…


This is another step-by-step walkthrough which explains how to dockerize and deploy a SpringBoot microservice behind Nginx.

This article aims at helping Java developers who want to start using popular tools (Docker, Nginx, DockerHub, Certbot) to create a production-ready application. It will also show how to obtain a (free!) domain, setup a (free!) SSL certificate and deploy on DigitalOcean. Some Devops for developers.

Why 1–2–3? Focus on simple essential aspects, clear code samples and relevant references.

Image by author

DigitalOcean

DigitalOcean is one of the most popular cloud platforms for deploying and managing applications and web sites.

The cheapest plan starts from 5$ per…


This is a walkthrough explaining how to Dockerize and deploy on Heroku a Python application using MongoDB Atlas.

Why 1–2–3? Focus on simple essential aspects, clear code samples and relevant references.

The Application

It all starts with source code of course, let’s create a Python app on top of the Flask framework.

The application provides few REST endpoints and a DAO layer to access the database.

# app.py from flask import Flask, request, Response import logging import requests, import os try: app = Flask(__name__) logging.basicConfig(level=logging.DEBUG) logging.getLogger('werkzeug').setLevel(logging.ERROR) except Exception as e: logging.exception("Error at startup") @app.route('/ping') def ping(): """ Ping the endpoint :return: """…

This is a follow-up to present the latest changes in this little hobby.. :-)

Tweesky has now a web site where you can generate, validate, customise(!!) and share your Preview Cards.

Ops, I almost forgot: while Twitter is still the main focus it also works on all major Social Media.

Knock yourself out my friend: tweesky.com

Create

Enter the URL to see the Preview Card and its main attributes.

It is free, simple and mobile friendly. 😀

Edit

Customise the attributes before sharing. Yes, you can.

It might be the case that the title or the description are not fetched correctly (your…


There is (obviously) lots of sharing of resources and links on Social Media (that’s the idea!) but surprisingly the nice Twitter Link Preview does not always appear.

This is not a great situation when you are growing your followers base, promoting you blog post or simply wanting to look nice and professional.

All Twitter gurus out there agree: the visual impact of the nice Card Preview is a must.

Twitter Summary Card

Why is that?

The Twitter Card preview relies on few simple markup tags:

<meta name="twitter:card" content="summary" /> <meta name="twitter:title" content="Beppe Catanese Github Home" /> <meta name="twitter:description" content="Personal projects (Java, Python, Chatbots, Date Engineering" />…

Beppe Catanese

Software Engineering, Data Engineering, Coder. And other hobbies too.

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