The Second 90%



A few years back I read a long lost article for indy game devs, that you should:

"Take your worst case estimate, double it and use that as your best case estimate."

This puts it mildly, but humans are for the most part really bad at estimating effort.

The standard project management aproach to managing large tasks with a high degree of uncertainty is to break down the large task into smaller and smaller tasks. The idea is that each task can be reasoned about and thus estimated to a higher degree of certainty. This is true, but...

In many project management software, you can show single task progress in percent. Unfortunately, almost all tasks in progress are pegged at 90% and the software will helpfully show nice charts. But this is misleading, since a task that is not done, is not done. A task has exactly 3 relevant states:

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Plausible Deniability in Threema



Threema’s private chat feature is worse than useless and desperately needs plausible deniability. The hidden chat feature must be implemented in a way that allows the user to plausibly deny that the a private chat actually exists, up to the point to unlock the application and “prove” it.

In the current implementation of threema, the following problems exist:

Problem 1: One Passcode

Threema uses the same passcode to unlock the application user interface and to show private chats. The problem here is that this only one security token, that once revealed basically renders the remaining safeguards null.

Problem 2; Show Private Chats Leaks Information

The “Show Private Chats” divulges the current state of the application. First this user interface element is only visible when there are private chats. This leaks the information that there is more to get.

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How To Get a Stack Trace on Windows



Getting a stack trace from a C++ executable under Windows is not trivial. The key problem is, that in C++ there is no simple stack_trace function and the Windows API only provides StackWalk, not some handy function like glibc's backtrace function.

I will show you how to get a perfect stack trace under windows for all your logging and debugging needs, like such:

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