The pivotal IBM IoT and AI Salon on January 16th at the Fat Cat Lab, Greenwich Village, NYC was an amazing event. More than 100 participants attended to interact with a full day of talks, lunch and workshops. I, Grant Steinfeld, was honored to present a lightning demo/talk of a global satellite Rock7 module tracking prototype.

Self contained transmitter unit — Satellite Modem + Raspberry Pi + Powersupply + Monitor + Keyboard

Along with a fellow developer advocate, Justin Halsall, we simulated a scenario of sending an SOS message from a ship in the open sea using this unit. The message sent via a touchscreen enable raspberry pi hooked up to the module, made it’s way…


Accountants don’t use erasers or they end up in jail. When an entry is made in the accounting records, it will live forever. There may be another entry added to ensure that a mistake is corrected but the mistake will not be erased.

Storage is cheap these days! So save all events!!

“Move beyond CRUD towards Event Sourcing/CQRS to scale state in an event-based design “ Jonas Bonér

No more need to update nor delete data?

Do you Create ( add ) new data — yes!

Do you Read ( existing data ) — yes!

Do you Update (existing data ) — -no! Why? Disk space is cheap these days! — use event logging

Do you Delete ( existing data ) — no! Same reason, RDBMS allowed this but this violates — Accounting practices — https://news.ycombinator.com/item?id=15113079 ( of course it should be possible for GDPR etc! )

So this is the…


Blockchains are the distributed ledger technology underlying bitcoin and other cryptocurrencies.

More broadly, a blockchain is a mechanism for updating truth states in distributed network computing, producing consensus trust and serving as a new form of general computational substrate.[1]

Image from Google https://bit.ly/2LO0cle

These state transitions are expressed programmatically with logic that is executed which affects the way data is written to (appended) to or read from the actual blockchain ledger. Where are these computations be performed? They are expressed as software logic as Chain Code also known as SmartContracts ( There terms are interchangeable and mean the sam thing ), which epitomize the rules or businesses logic that define the day to day operational transactions performs between members of a blockchain network.

Are there really millions of ways are the ways to craft these?

Certainly a million is a bit of an…


OpenShift is touted as “The Kubernetes platform for big ideas

Empower developers to innovate and ship faster with the leading hybrid cloud, enterprise container platform” RedHat OpenShift homepage

As many of us technologists have, I’ve also been checking out the usual candidates like docker-compose, k8s as well as Minishift/OKD OpenShift. …


The average person has an attention span of 3–5 seconds. If you don’t fully engage a user during this time frame, they bounce. The longstanding pressure to write faster code affects every single one of us, every single day. And it’s only getting more intense as the technology develops. The more options users have the less patient they become.

Grant Steinfeld (@gsteinfeld) is an IBM Developer Advocate for Blockchain and Java/JVM

The software industry offers many solutions to this issue but most of them are convoluted and tricky, and the dilemma then lies in the choice of architecture.

The Actor Model is a great solution. It allows you to create responsive and reliable applications that provide the kind of interactive experience users are looking for.

What is the Actor Model? First introduced by Carl Hewitt in 1973, the Actor Model was inspired by things not normally associated with computers, like physics — quantum mechanics and general relativity — and…


It’s a fantasy to imagine that any system will ever be 100% safe. The fear of cyberattacks, theft and hacks is always going to be very real, especially when you’re dealing with super sensitive data — personal medical data or product cost, volumes and markups.

One way to prevent anyone interfering with your data is to store it on an immutable blockchain, like Hyperledger Fabric (HLF). You can build private permissioned blockchains with the framework, where data is tamper-proof, secure, and visible only to explicit organization in its network.

HLF is a highly modular blockchain system. It has been designed…


I’m always looking to create strong but easy to remember passwords

I like passphrases of a song or poem I like. For example

The lyrics I love from , Starman David Bowie

Didn’t know what time it was the lights were low
I leaned back on my radio

makes me a memorable passphrase like

DkwtIwTLwL!lb0mr

if you can’t think of a song or poem or phrase you rememberwell.

I do it programmatically

first use brew to install pwgen

$> brew install pwgen

then edit your ~/.profile

and add a function like

function mkpwd {
clear
openssl rand -hex 10…


I’ve find I have been building wooden benches over the years.

Here they are

Redwood balcony bench ( 2010 )

Reversed curve carvel `Boat` Bench (2013)


Ship in dry dock for yearly inspection by specialized instrumentation.

I am a developer advocate at IBM specializing in blockchain, and I recently spoke to a good friend whom is also a surveyor for the Maritime division of a global assurance company. Assurance companies underwrite risk and ensure safety of materials and heavy equipment and vessels like ships. He was curious about blockchain technology and how it can make his job more efficient and understand the current activity and research around blockchain going on at his Company.

Currently he needs to evaluate ships and their constituent parts with respect to their integrity for the safety of the vessel and its…


I am a Type I diabetic since 26 years ago. I now no longer really feel when I get a low sugar ( hypoglycemia unawareness ). I wear the Dexcom sensor + transmitter and get readings and alerts on my iPhone, mostly. Transmitters batteries go flat and need replacement, sensors fall / tear off and of course iPhone gets broken/lost or out of range.

My awesome Endocrinologist, Gillian Katz MD, recommended I get a diabetic blood sugar alert dog. Yes dogs fine sense of smell allows them to detect your sugar levels on your breath.

Normally the training for your…

Grant Steinfeld

Grant is a Developer Advocate at IBM, specializing in Blockchain, NodeJS and Java. An accomplished and innovative senior Software Architect and Engineer, he is

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