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© 2006-2017 Andrew Cooke (site) / post authors (content).

OOPSLA / Crystal (Agile)

From: "andrew cooke" <andrew@...>

Date: Sat, 28 Oct 2006 14:42:46 -0300 (CLST)

This is a bunch of notes based on the Tutorial with Alistair Cockburn at
OOPSLA, 23 Oct 2006.  It's the third version.


Perhaps the biggest thing I finally understood is that Agile (or, at
least, Cockburn's take on it) is flexible.  There's no one right way and
each project requires not just its own methodology, but also
frequent reflection and revision.

(At the same time, there are a core set of targets ("properties") and
general approaches.  I will give some of these later.)

Acknowledging this flexiility, Cockburn recommends a regular
"reflection workshop" where people discuss the previous iteration (or
whatever - once a month was suggested at one point), identify things to
keep, things to try, and problems that need to be elevated to

This relates to the quality talk at ADASS and comments Evan has been
making recently, I think.

But there's also another, related angle.  Agile isn't just about
technical decisions.  Or rather, technical discussions aren't always
conclusive.  There's a very important reliance on inter-personal
skills and negotiation so that the team as a whole can resolve
conflict.  This goes further than someone making a final technical
decision - it's about "vibes": trust, mutual respect, understanding...

A quote from one of Cockburn's slides on personal safety: "Can you
disagree with your boss about the schedule in a team meeting? [...] Being
able to speak when something is bothering you, without fear of reprisal." 
Do we pass this test?


Cockburn repeatedly emphasised delivery.  Frequency of delivery, not
"iterations" (planning cycles) is a core property of Agile; focussing on
iterations at the expense of delivery is a common problem.

In June/July/August(?) we pushed hard for delivery of a
feature-complete, but unreliable, system.  In retrospect some parts were
over-complex and the architecture lacked a unifying, layered
approach to metadata.  It was a very immature product.

But it was a product, and we were close to delivery.  Instead of
delivering, and scoring an early victory.  I'm curious why we didn't carry
this through (and in an agile team with good communication,
surely I shouldn't be confused about this).

A related point was the idea of a "friendly user".  Someone we can deliver
to internally.  Obviously this works better for client
software; in the context of our system it seems to be mainly an
argument for less formal delivery processes.

Remote Teams

While disclaiming expertise in this area, Cockburn made a number of
recommendations.  The most important was the need for "discipline" - a
stricter adherance to the Agile principles.

I think this makes sense, but "discipline" is a tricky thing to
understand.  The following quote was helpful: "High discipline teams work
in the same way all the time, by personal choice."

So discipline is an internal thing each developer cultivates; it's not
enforced directly from outside.  The question then, is how to instil this.
 See communication issues.

Are we disciplined?  One measure of this is the common architecture. Can
we all write down the architecture?  Do we agree on it?  I think we are
getting close to this.

Personally, I also wonder if we should all be using a common

Apart from discipline, the following points seemed relevant:

- To convey detailed information to remote sites, video a whiteboard
  discussion and email the video.

- Daily group phone call.

- When working remotely, lack of trust is a particularly serious

- Encourage community.  Photo board.  Postcards.  A collective
  identity.  Morale is critical.

- Methodology may change with locale.

- There was an example of a very distributed team (many people working
  from home).  One person had a job which was solely to visit
  everyone.  The communications hub.

- Information radiators (public displays).  How do these work
  cross-site?  Maybe before we ask if these canbe seen in the South we
should ask if they exist in the North?


From a list of 7 properites of successful projects, 3 were highlighted
as critical to Crystal (Cockurn's thing):
  -- Frequent delivery
  -- Osmotic Communication
  -- Reflective Improvement

Osmotic communication means that even if you don't know what was said, you
know who was talking and what the subject was.

It's interesting to consider how we score against these points.

"Monitor the project by the quality of communications and morale in the

Problems implementing Agile, it seems to me, are caused not just by a lack
of technical knowledge, but also through a lack of "people

Other Observations

The following points seemed interesting, yet don't fit in the text above

- Our code development steps are not small enough.  We are not
  committing sub-day (hour scale) chuncks of code ("episodes").

- "Does it take less than three days, on average, to get an expert to
  answer a question?  Can you get an answer in a few hours?"

- Get everyone together.  Everyone makes two lists - things they liked
  in a previous job and things they want to avoid.  Look for antidotes to
the bad things in the good things.  There will be disagreement.
Inter-person skills are essential.

- Code is public.  What does this mean?  Team needs to discuss this.
  One solution is to have an owner responsible for integrity of code
(doesn't mean it's not public).

- Writing stuff down is a warning sign that the steps are too big.

- User viewing.

- On a team of 45, one person has 50% time researching code on the

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