Friday, October 26, 2012

On Being a Senior Engineer, Estimating

So, I'm moving from being a freelance consultant to a "technical lead". While I feel that I have a lot of skills in that area already, I'm always looking to grow.

So with that I'm going to be adding some posts about what it means to be a technical lead.

Also, I'm thinking about designing a presentation around estimating, because that is something that I want to learn more about. So I'm also going to be adding some estimation research up here.

And of course, other technical discoveries, AS3, flex, and others will always be here.

So I just came across this blog, On Being a Senior Engineer which I think is fantastic, and here are the bullets:

  •  Mature engineers seek out constructive criticism of their designs.
  • Mature engineers understand the non-technical areas of how they are perceived.
  • Mature engineers do not shy away from making estimates, and are always trying to get better at it.
  • Mature engineers have an innate sense of anticipation, even if they don’t know they do.
  • Mature engineers understand that not all of their projects are filled with rockstar-on-stage work.
  • Mature engineers lift the skills and expertise of those around them.
  • Mature engineers make their trade-offs explicit when making judgements and decisions.
  • Mature engineers don’t practice CYAE (“Cover Your Ass Engineering”)
  • Mature engineers are empathetic.
  • Mature engineers don’t make empty complaints.
  • Mature engineers are aware of cognitive biases


And some of the points about estimation:
Estimation is really about responsibility

(Quoted directly from the blog)

From the Unwritten Laws:
Promises, schedules, and estimates are necessary and important instruments in a well-ordered business. Many engineers fail to realize this, or habitually try to dodge the irksome responsibility for making commitments. You must make promises based upon your own estimates for the part of the job for which you are responsible, together with estimates obtained from contributing departments for their parts. No one should be allowed to avoid the issue by the old formula, “I can’t give a promise because it depends upon so many uncertain factors.”
Avoiding responsibility for estimates is another way of saying, “I’m not ready to be relied upon for building critical pieces of infrastructure.” All businesses rely on estimates, and all engineers working on a project are involved in Joint Activity, which means that they have a responsibility to others to make themselves interpredictable. In general, mature engineers are comfortable with working within some nonzero amount of uncertainty and risk.

And there is a cognitive biases (one of my weaknesses) around estimating

Planning Fallacy – (related to the point about making estimates under uncertainty, above) basically: being more optimistic about forecasting the time a particular project will take.



Thursday, October 25, 2012

Remote Debugging a swf on Android

So I recently had a very thorny challenge of debugging on android.

Because of business / technical reasons, we HAD to serve the swf via HTML through a specific server. The problem that I was having was that the at full screen the video went blank, although we could hear the audio.

Now just as some background, the project was inherited and while there was a decent MVC architecture in place, it was possible that any element on the screen had access to any other element and could modify its properties.... which happened quite a bit.

My challenge was to try to figure out how to get *some* information out of the device so I could have a clue as to what was going on.

I tried to reverse tether and proxy, but neither of those I could do without rooting, which I wasn't willing to do.

Then I tried setting up a hotspot from my laptop (http://www.connectify.me/) to see if I could get Charles in place to then do a local mapping which I could leverage for remote debugging in the IDE, but my version of Android didn't like ad-hoc networks.

Finally I discovered that Monster Debugger had a P2P version. This version allowed me to run demonster on my desktop and the app on the device and as long as they were on the same wifi network, I could get some telemetry. ROCK ON!

So I created a MonsterTraceTarget to go with my logging, and I got trace statements. I could also drill into the visual hierarchy and validate and set properties.

After much searching I found the video element about 16 levels deep with a width and height set to 0,0. This explains the audio but no video. Traces confirmed that somewhere in the code we were hitting the video api (not AS3, but a wrapper to the 3rd party video provider) and actually setting these crazy properties.

"Find Uses" (thank you IntelliJ), led me to half a dozen places where this could happen. More trace statements to determine which one was the culprit. Iterating on the "find uses" and trace statements, I finally discovered that it was an omission that had happened *months* earlier (so much for test early, test often), where there was a conditional test within the configuration startup for touch device and full screen (duh), where the stage rectangle was supposed to be calculated, but wasn't - hence the zeros.

Huge thanks to Demonster and IntelliJ for the tools needed to solve this 2-days-worth-of research thorny issue.