Guest Post: The Five Stages of Debugging

We Product Manager sometimes can't understand why the product bugs we complain about so vociferously take so long for Engineering to fix.

Well, here is the developer's point of view when faced with a nasty bug. It's an extremely well-written guest post by an engineer who is a fan of this humble and cantakerous blog. Thank you, A. Working Coder!

The Five Stages of Debugging

by A. Working Coder

Being confronted with a serious and difficult-to-diagnose bug can be one of the most traumatic and stressful experiences of a professional programmer's career. Those who have been through such an ordeal rate the stress as on a par with that accompanying serious injury, divorce, or the death of a family member.

Researchers who have studied the psychology of computer programming have lately constructed a framework to understand the stages through which the programmer's mind progresses as she/he works through the difficult process of resolving a bug.

These stages are similar in concept to the well-known K├╝bler-Ross Stages of Grief, and for similar reasons. Like death and its attendant grief, fixing a bug is a process initiated by an event, at first unbelievable, which causes great anguish in the affected mind. However, this event must eventually be grappled with, endured, and brought to a satisfactory conclusion.

Understanding the stages of bug fixing will make us better prepared to survive, persevere, and eventually bring closure ... to our bug queues.


How you're feeling: Skeptical. Offended. Petulant.

  1. Ignore it.
    Maybe it'll go away.

  2. Mark it as "Works for Me"
    Maybe it was user error, or a local configuration problem. Yes, I'm sure that's what it was. It'll just go away.

  3. Call it a Glitch.
    I think it was just a weird one-off that nobody will ever see again. There's no point in figuring out what went wrong. The {database/network/browser/something} hiccuped and that's all this was. It won't come back, I'm sure.

  4. Hide.
    I'm taking a couple of days' sick leave. Maybe they'll assign the bug to somebody else.

  5. Mark it as "Working per Spec".
    Hey, look, I just implemented what was spec'd. If they want to change the behavior, UI will have to update the spec. Maybe they'll decide they can live with it as-is.

  6. Demand More Information.
    I can't do a thing with this bug until and unless I see the error logs for this particular exception scenario.

  7. Assign it to another team member.
    I was getting badly-formatted data from that other module, that's the problem. Give it to the guy who maintains that module. I could check for that one weird corner case in my module, but the proper fix is for that other guy to make his code correct. He's offshore anyway, so I'll never have to face him.


How you're feeling: Resigned. Defeated. Annoyed.

  1. Accept it.
    All right, all right, all right! It's my bug. I'll fix it.

  2. Put it on the bottom of your queue.
    Maybe I can find another job before I'll have to fix this bug.

  3. Bargain with your manager.
    OK, look: I could fix it the right way, and that will take a month. On the other hand, I could apply a band-aid to the problem, which won't really solve it, but it'll make it go away as far as the end-user is concerned. And that will take a couple of days.

  4. Mark the bug with an outrageously padded estimate.
    God, I hope that's enough time.


How you're feeling: Giddy. Light-headed. Nauseous.

  1. Initial Research.
    I can do this. I can do this! All it takes is a little organization, a little focus, a lot of caffeine, and a little time. I can do this.

  2. Befuddlement.
    Shit. This is unbelievable. I can't make heads or tails of this code. It's a mess. It's a mystery to me how this code could even compile, let alone work. What chance do I have to figure out how it can fail?

  3. Hide Again.
    Look. I'm sorry. I had to have my appendix removed. Again. Yes, now that you mention it, I did used to have two. Now I don't have any. Happy now?

  4. Bitching.
    Well, what did they expect, anyway? Trying to do this without so much as a decent debugger. What am I, clairvoyant? I had better debugging tools on my Commodore 64!

  5. Spitballing.
    What if I try ... this? Nah, that doesn't work. How about ... that? Nope. How about ... that? Shit, that makes things worse.

  6. Despair.
    I'll never fix this bug. I'm a lousy coder. I'm stupid. What am I doing here, in a place full of smart people? Sooner or later they're gonna catch on, and then I am finished around here.

  7. Humiliation.
    My manager asked me why I've taken the better part of a month to fix a bug I'd spec'd out as taking a couple of days' worth of work. I don't know how to read the logs and I broke my own build scripts. Now I'm afraid to ask for help because it'll just make me look stupider than I already do.

  8. Panic!
    This thing is way more complicated than I thought it would be! The parts I thought would be really hard turned out to be really easy ... and the parts I thought would be easy turned out to be a complete rewrite of about a half a dozen classes. Why did I ever tell my manager I could do this?

  9. All-Nighter(s). Withdrawl from friends and family.
    (incoherent mumbling, punctuated by bursts of loud profanity.)


How You're Feeling: Grateful. Relieved. Awfully Impressed with Yourself.

  1. Revelation.
    Oh! Now I see how to do this...

  2. Write the correct code.
    I am so good. I am a coding machine!

  3. Test it.
    Yes! It passes that test. Yes! It passed that test. Boo! It fails that test. And I have no idea why...

  4. Hide the test failures.
    It's a totally unrealistic corner case anyway. Nobody will ever see that in the field. It was really a pointless test.

  5. Check it in.
    I'm awesome. Is there pie in the kitchen?

  6. Close the bug.
    I heard there was pie in the kitchen.


How You're Feeling: Twitchy. Nervous. Superstitious.

  1. They've Reopened the bug.
    Really? They found another way to break it? Shit - it's that corner case I swore would never come up.

  2. Fix the fix.
    Yes, I'm even checking cases where the employee age is an imaginary number, just to be sure.

  3. Close the bug.
    Yeah, bitch. You're closed. Once and for all. Now stay dead!

  4. Vow to never take on such a task ever again.

  5. Realization that you are now considered the expert on that module.
    Oh no! Now I've got three new bugs on that module.

At this point, you are expected to:


Furthermore, as a working coder, you will:

    Death OR Retirement OR Promotion_into_management

Sue Raisty

Product management geek, born-again engineer, adoptive mother of boys, coach & mentor, mountain trail runner, tinkerer, no-bull communicator, wannabe writer, room mother & compulsive researcher.

Silicon Valley, California