We should track our decisions in a decision log
Contents
When we need to make decisions we may schedule a meeting, or start some POC or just lead by example. We’ll need to properly explain our idea, present pros and cons and communicate it well to all interested parties. A process we’ve been using for this is to create a decision log document.
This is similar in concept to a RFC but the semantics are different. While on a RFC the focus is on how we’re doing something and specific details, the decision log is all about presenting ideas and reach an outcome.
Should we use some new technology? VueJS or ReactJS? Should we use a specific language for that specific service? Should we enforce all pull requests to run a build pipeline? How many people should review pull requests? Could we change the sprint duration?
There are always lots of questions and decisions like these. A good way to handle them is to register them on a decision log and then bring them for discussion. We’re currently using this with good results. This is specially useful on a remote team with working hours that don’t overlap. We need to communicate async and have everything registered for our future selves.
My mantra for remote teams is: “What is not written does not exist”. - Interview with João Cavalheiro
The process
When someone wants to discuss a new decision the first step is to create the decision log document. Giving proper context, presenting pros and cons and clearly explaining why we need a decision.
This should be time boxed. And we should summon all the interested parties. Naturally we may have some people that don’t really care about some decision. But we should also have a healthy discussion. The document should be updated with the feedbacks that other people present.
When we reach the decision time, we should have a proper document that will explain to future developers (and ourselves) why something was decided.
Who decides on the outcome?
This depends on who are the main stakeholders. If the decision requires investment in time or money we may need approval from higher-ups. If this is the scenario we should adapt the communication. Less technical talk and more focus on added value.
If the decision is in the scope of the team, we may need to consider power dynamics. Do we have a team leader that is responsible and wants to decide? On my teams I usually delegate the outcome for the creator of the decision log. I will expect all feedback to be taken into account on the decision.
What about changes to the decision logs?
The great thing of having this document is that we start referencing it whenever we need to explain something. We may be reviewing a pull request with something that doesn’t comply with a decision log, and we link it for context. The pull request’s author will have all the discussion and clearly understand why something should be followed. An example would be a decision log for adding code documentation to all public methods, JavaDoc style.
But we may have people that didn’t pay much attention on that decision log and that don’t agree with the decision. This is tricky and denotes a problem in the process. Because this feedback should have been already taken into account.
When this happens I suggest the creation of another decision log. This may seem too formal and slow. But having a track record of the timeline of all decisions regarding some topic should be the main goal.
Tracking results
Having the decisions detailed is great but we can do better. Each decision log should be a living document and we should revisit it from time to time. If for example we decide to use a specific database for a specific context, we should register on the document what ended up happening. For example after the first month we could write our first impressions. After a year we should register a review of the solution, and include all that we have learned so far.
This allows us to iterate and improve. Registering our findings will contribute to our continuous learning process. If we don’t register this information it will be lost. We may have something that didn’t work out on one scenario, but is hugely successful on another scenario. Having this on the decision logs will help on understanding the different use cases.
Summary
I’m going to start registering on the blog several decision logs that I’ve created and also the results over time. Topics like:
- What sofware engineering KPIs to track
- Having a formal QA process without manual tests
- Enforcing 100% code coverage on some projects
- Enforcing strict linting rules on the build pipelines
- Using result based APIs
- Following a zero bug policy
I’ll write why I believe some action is important, the pros and cons, and after some time I’ll review those decisions. What were the benefits and the drawbacks? Would I do it again? How could these decisions be better?