Software architecture

Musings in a car museum.(Museums are for musing, aren't they ?)

-Kalyan Mysore

A mind cross-linked !

• A week of software architecture.• Work ricocheting in the mind into the

weekend.• A weekend visit to the Mercedes-Benz car

museum (Stuttgart, Germany) at the same time !

• So, I saw software architecture in car history !• Here’s a walkthru !• (All pictures thru my camera. Just for fun. No harm intended.)

First usable architecture

• 1883 – Daimler and Maybach• The world’s first high speed

gasoline engine.• A.k.a. Grandfather clock.

• Met quality attributes:– Power output enough to drive

a vehicle– Small enough to fit in vehicle !

A test harness !

The world’s first motorbike was a test harness for the world’s first high speed gasoline engine ! 1885

The architecture refactored !

• Quality attributes to be met:– More seating– Go on rails

• First gasoline powered railroad car ! 1887

• Same grandfather clock engine, with refactored shell !

More refactoring

• Quality attributes:– Facing seating

– Shade from rain and Sun

– Lights for low light conditions

• 1893

Just another refactoring

• Quality attribute:– More payload

• 1898

Getting the quality attributes right. -1900

• Safety– Low center of gravity.

• Stability– Long wheelbase

• Speed– Powerful engine

• Not just a “horseless carriage”. An architecture for a modern automobile !

Just a few more refactorings

• 1939 320 streamliner

The bus is just a big car !

This architecture even supports apps !

You thought skins are a new concept ?

If there’s twice the power..

• They couldn’t resist putting twice the load and slowing it down !

The original “cab” file !

• The driver probably even carried a manifest !

Bells and whistles !

• If you don’t like the ride, change the steering wheel, add a few dials and horns and you’re so busy you don’t notice the ride anymore!

The diesel engine

• A rare change in the “core” architecture ! 1923

The diesel, refactored for boat use.

When great architecture and great UI co-author a product

• An emergent design of great beauty !

The Kling-on the race track

• No standards to meet

• Its just a race to the finish

• If your design is agile,you win the race

• Its not Time to marketBut mark your time !

A failed architecture for a flying car ?

• If they tried and failed, they put a cool marketing spin on it. We’ll never know !

A new “framework”

• Just 110 pounds for framework. Light weight !

• But needed the special door. – And we thought they wanted to fly !

Variability variety !

• An architecture that can sustain this large a variability ? Amazing !

This architecture never needs policing.

Crash proof the architecture

• Add a spike to chain it down.

• If you try, it will catch !

If the architecture doesn’t shine thru

• Add a few lights !

Want to run a “smoke test” on this ?

Many a time, safety is an afterthought, following performance.

An attempt to add a quality attribute…

• Add “high efficiency” but lose “seating” !!

• Hmm. Is that tradeoff good ? If you’re off to a tradeshow…

Finally, efficiency and thruput !

Got an efficient but ugly architecture?

• Hide it under a nice “façade” !

Someday !

• Software architecture will have magazines like this !

Special purpose architecture

• Optimized for the quality attributes of speed and maneuverability. All else secondary.

Architecting for cool !

• What were the quality attributes they architected for? Coolness is definitely at the top !

More special purpose architecture

• If your quality attribute is “1000+ km on a gallon”

Just another car under the Sun !

Should I buy it?

• They sell it in the museum ! But my suitcase is a bit small. Besides, it looks like goldplatedarchitecture !