logo
Duncan Cragg on Declarative Architectures
About All Things...
...taking programming beyond:
Threads, Message Queues, Client-Server, CORBA, Web Services, SOAs, Agents, Synchronous Architectures, Imperative Programming - and even Applications, Desktops and Documents
Duncan Cragg...
...works for ThoughtWorks UK; originally from April 2002 to July 2007 and now recently re-joined. Previously worked as a Web Architect for the Financial Times.
...went to both UCL and Imperial College of the University of London (in the Eighties); specialising in Logic during his MSc.
...wonders when his LinkedIn Account will be useful
...has a phone-cam, and used it on himself once, just before his weekly shave:
Photo of Duncan Cragg
...can be contacted by and followed on Twitter.
Posts tagged 'declarative' Atom Feed for Posts tagged 'declarative'
 
 
EUP, IoT, AR and Minecraft | NetMash | Object Network
February 10, 2015 15:58

These days I seem to mainly use this blog for once-a-year announcements of what I'm up to, which is useful as record for myself when I need to reflect.

So here's where I'm at, as 2015 begins..   ...

 
The Object Network Approach to Augmented Reality and the Internet of Things
March 1, 2014 11:24

After filling up that other blog recently with 61 pages of content, one page a day, I was challenged by my ThoughtWorks colleague, Andy McWilliams, to help him get in more easily to my explanations of the Object Network applied to Augmented Reality and the Internet of Things, especially around how my approach differs and is better than other approaches.   ...

 
Building The Object Network
January 27, 2014 11:36

I've started another blog called Building The Object Network, about how I'm experimenting with Augmented Reality for the Internet of Things using the Object Network approach.

So far I've been blogging every day.

Do subscribe!   ...

 
Cyrus in 2013
January 16, 2013 17:09

Well that worked out pretty well: I have a 3D environment on Android programmed in a simple but powerful declarative language which I've called "Cyrus".

Cyrus basically uses JSON all the way through: from user interface and scene graph to rewrite rules, on the wire and on disk. The Cyrus programming language is essentially JSON itself, as JSON rewrite rules. I've reduced the noise of JSON in Cyrus by taking out redundant double-quotes, square brackets and commas. It looks very nice to me.   ...

 
Empowering the World | NetMash
August 17, 2012 11:11

If you also think that hacking up 3D worlds on Android could be fun, then join me! Stuff you should expect to play with if you want to get involved includes Java, Android, OpenGL ES 2.0, 3D model creation, hyperlinked JSON and JSON rewrite rules. Creatives, evangelists and inspirers are also very welcome to get involved!

The idea is to make an app (NetMash) that lets people build, mash up, animate and program 3D worlds, shared online and all linked-up, Web-like.

Like creative-mode Minecraft, but adding easy in-world programming and shared online by default. Or maybe a bit like an open, distributed, generic, mobile Kodu (or here), for adults as well as children.

NetMash is intended to deliver creative empowerment to ordinary people. We professional software folk often get stereotyped as geeks, and the creative fun we often have dismissed as in some way unusual. That's a real shame, because such prejudice means that the other 99.9% of the world are simply missing out on the joy of experiencing the most creative and empowering activities humankind has yet invented.   ...

 
Fun and Virtual Worlds | NetMash
August 15, 2012 11:37

I just re-read my article on the Universe Web. I think it's pretty good. Indeed, to be honest, "programming as Cyberspace building" is where my heart has always been, and I'm all about following my heart this year. Especially if it's more fun, for both myself and others! Or if it opens up new worlds to new people.

In contrast, I don't see "fun" in W3C or IETF activities. Indeed, there's recently been a number of examples of tension in that world, between stabilisation and innovation, idealism and pragmatism, Enterprisey and Webby. Interestingly, all those examples have a "2.0" flavour: HTML5 (Web 2.0), HTTP 2.0 and OAuth 2.0.

My own interests are rough consensus and running code; innovation and pragmatism. Webbiness not in the W3C sense - "Web" Services, Semantic "Web", "Web" Sockets, etc. - but in the sense of "the simplest thing that works". Which is the Web of HTTP (1.1), URLs, JSON and REST, or specifically my FOREST interpretation.

I crave the simple and powerful, the cool and the fun. Which ultimately leads to the kind of thing I was describing as the Universe Web. And to be honest, I'd like to write and code for me, not for my peers and colleagues or for my career.

So, to the pursuit of pure joy in place of compromise, I'll now be focusing my energies on the journey of evolving the NetMash Java server and Android app towards an online, open, hyperlinked virtual world that is programmable in-world by users using simple rules.

Stay tuned!

picture   ...

 
OTS: The Benefits of both Native and Web Mobile
May 10, 2011 11:11

The Web, in its purest form - declarative HTML and CSS documents, XML feeds - is mashable, linkable, sharable. It's easy to create documents that slot into the global Web and can be accessed on any device; accessed by just a simple link. Servers can easily scale through statelessness and cacheing.

Native Mobile Apps are fast and slick. They are intimate with the dynamic, interactive, tactile mobile user interface, intimate with the capabilities of the device and intimate with the domain of mobile: photos, locations, contacts, messages.

OTS is a simple, clean, powerful approach to delivering Mobile functionality and content that is designed to realise these benefits of both Native Apps and the Web.   ...

 
JSON-Mash
March 18, 2010 16:58

Around the middle of February I completed a basic persistence and networking implementation for Fjord, then had to do other things for a month. Just recently I fixed Fjord to work with the latest version of the Node.js APIs.

Next project: I'm going to use Fjord in a Web Framework to be called "JSON-Mash".

I intend to show that JSON-Mash will be a great framework for rapidly building truly interoperable and truly scalable online and distributed functionality.

Here's how JSON-Mash will work.   ...

 
Introducing Fjord
December 11, 2009 08:22

Following on from my recent article where I derived FOREST, this article offers the beginnings of a JSON unification and rewriting language that can be used in a FOREST architecture.

Why JSON, not XHTML, now? Well, I recently discovered that JSON is overtaking XHTML in interest, and I was further inspired by Kris Zyp's recent announcement of his JSON Schema Internet-Draft.

Fjord is a language for describing how the state of a JSON resource at any time depends on both its current state and on the state of other JSON resources that it links to via hyperlinks.

Fjord is a Norwegian word, probably pronounced 'fiyourd', and might stand for some combination of the words: 'Functional JSON Object/Observer Resource/Rule/Rewrite Dependencies/Declarations'. Or maybe it's just because they're truly awesome, an' I wanna go.

Fjord also gives me an opportunity to show some examples of the "end-user" view of a FOREST interaction; starting with a simple finance example.   ...

 
Web Objects Ask, They Never Tell | The REST Dialogues
August 13, 2009 11:43

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for a few of the many function calls that they make available via SOAP.

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 9: Web Objects Ask, They Never Tell   ...

 
WS-Are-You-Sure | The REST Dialogues
July 16, 2009 16:16

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for a few of the many function calls that they make available via SOAP.

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 8: WS-Are-You-Sure (Security, Reliable Messaging and Transactions)   ...

 
Mobile Widgets aren't the Mobile Web
February 11, 2009 16:20

Mobile Monday London met last night to discuss the Mobile Web and Widgets. It was an engaging and thought-provoking evening.

Your intrepid reporter was there and, in spite of the crashing of his sad, clunky old Windows Mobile Xperia X1, losing all his notes, he brings you this hot report from right out of his memory (somewhat steamed up by subsequent socialising, but reclarified by Google).

After that, I give an explanation of why I believe that Widgets are not the solution to what Mobile 2.0 needs...   ...

 
The Mobile 2.0 Killer App is the App Killer
December 19, 2008 17:05

Mobiles are unique - if you want to miss out on the opportunity they represent, you could choose to see them as just slow computers with tiny interfaces and dodgy Internet connections. Then try to squeeze in your traditional applications; try squeezing the office desktop metaphor with its sedentary documents into a device the size of a mouse!

Alternatively, see them as the most personal, social and dynamic of devices that are becoming connected to the Internet. Now a multi-billion-scale global opportunity opens up to you. That's customers and dollars! In trying to grasp this, some are calling it 'Mobile 2.0', by analogy with its sibling, Web 2.0.

In that light, the Killer App for Mobile 2.0 is the sharer, masher and updater of People, Things, Times and Places... The key to getting Mobile 2.0 right is for it to merge seamlessly into our lives. That means the handling of dynamic and shared data becomes the top priority, even above the handling of applications.

This article describes a Mobile 2.0 platform that makes people and their stuff first class - not applications.   ...

 
Business Conversations | The REST Dialogues
December 11, 2008 11:45

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for a few of the many function calls that they make available via SOAP.

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 7: Business Conversations   ...

 
The Universe Web
July 18, 2008 19:49

Since the announcement by IBM and Linden Lab that OpenSim can talk to Second Life, I've been thinking again about RESTful Virtual Reality.

I'm not the first, of course. Others have been motivated by the same goal: To bring the Web's scalability, linkability and interoperability into Virtual World platforms.

Ultimately, how to use the same techniques as the Web to link Virtual Worlds together into a single, massive 'Virtual Universe'.

Here's how I would architect the Universe Web...   ...

 
Content-Types and URIs | The REST Dialogues
February 16, 2008 23:44

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for a few of the many function calls that they make available via SOAP (GetSearchResults, GetItem, GetCategoryListings, etc).

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 6: Content-Types and URIs   ...

 
Google Micro Conference
October 5, 2007 11:22

Last night's Google London Open Source Jam (also here) was on the subject of the 'Web' (didn't they invent that? Oh no, that was Microsoft).

This event has been getting better and better each time I've attended. There were some very interesting lightning talks held together with a tight structure and plenty of chance to chat, drink cold Leffe and eat cold pizza. And nick [transatlantic translation: 'steal'] the Green & Black's chocolate.

An ideal Micro Conference...   ...

 
How Ruby can enable the Web 2.0 Platform
June 26, 2007 15:17

Web 2.0's definition includes seeing the Web as an application platform. Which means it is in competition with Java and .Net, and with SOA, for both local and widely distributed applications.

If the Web is going to be a platform, the skills you need to learn to program it are the core Web 2.0 technologies such as Ajax, JSON, Atom, Microformats and OpenID.

And Ruby. This language, that's capturing the hearts of many Web 2.0 programmers, is ideal for easing the transition from the Java and .Net platforms to the Web platform, as I will show.

Even if you're part of a big company that is generally immune to the latest trends, the marriage of Ruby and the Web-as-platform may be something to prepare for. It could even displace your SOA agenda...   ...

 
The Distributed Observer Pattern | The REST Dialogues
June 20, 2007 22:42

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for a few of the many function calls that they make available via SOAP (GetSearchResults, GetItem, GetCategoryListings, etc).

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 5: The Distributed Observer Pattern   ...

 
Inter-Enterprise REST Integration | The REST Dialogues
April 8, 2007 13:38

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for a few of the many function calls that they make available via SOAP (GetSearchResults, GetItem, GetCategoryListings, etc).

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 4: Inter-Enterprise REST Integration   ...

 
Lighter-than Wins in 2007
January 18, 2007 11:12

What do all the MAJOR Web 2.0 technologies of 2007 have in common?

Let me list them first:

    M.icroformats (including tags)
    A.jax (including Comet)
    J.SON (plus YAML)
    O.penID (plus SXIP, LID, Yadis)
    R.EST (including Atom, APP)

What these technologies have in common is that they're all lighter than their competitors:

Microformats

Lighter than the Semantic Web

Ajax

Lighter than Fat Client (!)

JSON

Lighter than XML

OpenID

Lighter than SAML/Liberty Alliance

REST

Lighter than SOA

  ...

 
Business Functions | The REST Dialogues
January 10, 2007 14:21

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for a few of the many function calls that they make available via SOAP (GetSearchResults, GetItem, GetCategoryListings, etc).

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 3: Business Functions   ...

 
eBay's Working Architecture
December 14, 2006 14:15

There were two things I knew about eBay's Architecture - that they use J2EE and that they seem to like SOA. Both are approaches I give, ahem, special mention to on all my pages at the bottom of the left-hand column.

So it was with some apprehension that I opened up this (PDF) slide pack from Dan Pritchett and Randy Shoup of eBay, presented at SD Forum 2006 recently. I was expecting my prejudices around the issues and techniques of scaling web sites to be challenged, at least.   ...

 
Setting Data | The REST Dialogues
November 15, 2006 23:37

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for one of the many function calls that they make available via SOAP (GetSearchResults).

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 2: Setting Data   ...

 
Getting Data | The REST Dialogues
November 14, 2006 00:05

In an exclusive nine-part dialogue with an imaginary eBay Architect, we present an accessible discussion of the REST vs. SOA issue.

Although eBay have what they call a 'REST' interface, it is, in fact, a STREST interface, and only works for one of the many function calls that they make available via SOAP (GetSearchResults).

In this dialogue series, I argue the case for eBay to adopt a truly REST approach to their integration API.

Part 1: Getting Data   ...

 
The Right Way to do Ajax is Declaratively
July 13, 2006 14:33

Don't write your interactive Web application in custom Javascript! The Web's Declarative nature needn't be broken just because you want two-way dynamic data instead of one-way documents on your site.

Instead, write Declaratively to generic Javascripts, plugins and browser features such as Hijax, hInclude, XForms, SVG, XBL, etc.   ...

 
Web 2.0 and our Digital Rights
June 23, 2006 17:58

Open Data .. has .. recently .. been.. all .. over .. the .. blog .. o .. sphere!

Openness is a classic Us-and-Them issue. Big, nasty Apple/MySpace/Flickr is trying to control what little me/SingleStatus/Zoomr can do with my/our own stuff.

Open Data vs. Closed; Open Source vs. Proprietary; P2P vs. DRM; privacy vs. surveillance. The battles between the freedom of the pioneer, the individual and the minority against the rules and stability of the establishment and the majority form the endless shape of human history.

Us beating Them is Hollywood's favourite subject on-screen - and ironically Them fighting Us Hollywood's favourite battle off-screen.

As an Us-and-Them issue, with Us less powerful than Them, it's also tempting to give up and to follow the crowd - to do what we're told, to not ask for or sieze the privacy and open data we feel entitled to.

However, at XTech 2006 recently, there was a set of talks on the subject with a more positive approach.   ...

 
The 2006 'What Now How' Awards for REST Protocols
June 15, 2006 00:30

It gives me great pleasure to announce the 2006 'What Now How' Awards for REST Protocols (or 'APIs') in the Read/Write Category.

All this year's awardees share the distinction of being truly worthy of the 'REST' label; these Read/Write Protocols are acknowledged here for their uncompromising adherence to the simple principles of the World Wide Web.   ...

 
Microformats Challenge Web Feeds and Web APIs!
June 7, 2006 19:10

Microformats are subversive: they not only challenge the approach of full-blown Semantic Web approaches, but even question fundamental Web 2.0 building blocks such as Web Feeds and Web APIs.

I recently attended XTech 2006, where there were a few talks related to Microformats.

After summarising these talks, I'll finish with my shocking revelations about the subversive nature of Microformats!   ...

 
STREST (Service-Trampled REST) Will Break Web 2.0
May 25, 2006 19:05

The vast majority of supposedly 'REST' Web APIs are simply abusing HTTP to carry function calls. I call these APIs 'Service-Trampled REST', or STREST.

STREST APIs come with specific costs which could stifle the two-way data Web (Web2.0) if allowed to propagate unchecked. Although 'mashability' is a supposed benefit of the current proliferation of APIs, true interoperability and scalability can only be guaranteed by true REST interaction.

This is not an academic, purist or aesthetic stance, but one based on practical consequences, as I will explain.   ...

 
Excuse me - did you say 'Web' Services?
May 17, 2006 00:27

Distributing an application over a network isn't just a case of splitting it down a natural line and putting a network in-between. What works in-process simply doesn't work so well across the wire.

And just calling such an Internet version of application and process interfaces 'Web' Services doesn't mean it has anything at all to do with the Web, or that it in any way shares the Web's scalability, flexibility and robustness.

Indeed, I claim that you cannot distribute without also 'inverting'; you have to face what I call the 'Imperative-to-Declarative Inversion', if you really want a successful, scalable, distributed application.

Declarative Architectures such as REST (i.e. the Web, and now 'Web 2.0') dominate the broader Internet.   ...

 
The "Imperative to Declarative Inversion": Open Data is OK!
May 11, 2006 21:36

There is something about the Internet that nurtures open data, and something about computers that nurtures closed. It is often necessary, but often painful, to make the jump from local, closed data to global, open data.   ...

 
Welcome to 'What Not How'
March 22, 2006 17:00

Declarative Architectures focus on the What, not the How, of programming. The How has dominated the field - perhaps 80% of programming is done in the traditional Imperative style, where we tell the computer How to do a task in explicit steps.

I'd like to show in this blog how Declarative Architectures and technologies are not just an interesting sideshow to the main Imperative attraction, but a complete and powerful programming alternative in their own right - indeed, one which has already dominated certain fields.

Imagine being able to simply express What we want the computer to do - to give it constraints and rules - then let it work out for itself How to achieve our goals.

I believe that saying What, not How, will become the dominant paradigm in programming.   ...

 
 
Recent Posts
EUP, IoT, AR and Minecraft | NetMash | Object Network
CoAP and a Web of Things watching Things
The Object Network Approach to Augmented Reality and the Internet of Things
Building The Object Network
Cyrus in 2013
Empowering the World | NetMash
Fun and Virtual Worlds | NetMash
The Basics | The Object Network
Why we should link up our Web APIs | The Object Network
Introduction | The Object Network
OTS: The Benefits of both Native and Web Mobile
Mature REST In Six Lines!
Minted Media Types are Usually Less RESTful Than JSON
FOREST News
JSON-Mash
Tags