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How To Drive Change as a Software Engineer

Posted 2018-04-25
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You have an idea. Your boss is indifferent, your team-mates apprehensive, and that other team whose help you need are dubious. You are an individual-contributor with no direct-reports. You still think it's a good idea, but cannot make it happen alone. What next?

Driving change within an technical organization is hard, especially as someone with no rank or authority, but is a skill that can be learned. If you've ever found yourself with an idea but been unsure how to proceed, this post should hopefully give you a good overview of what it takes to conceive, plan & execute such an effort.

About the Author: Haoyi is a software engineer, and the author of many open-source Scala tools such as the Ammonite REPL and the Mill Build Tool. If you enjoyed the contents on this blog, you may also enjoy Haoyi's book Hands-on Scala Programming

While software engineers get a lot of autonomy, there are always things in an organization that you, as an individual-contributor, cannot "just do":

These may be easier for some Director or VP to mandate by fiat, but as an individual contributor, possibly a fresh-college-graduate, things are not so easy. Nevertheless, it is possible for someone with no formal authority to push through such initiative: I have seen it happen, and I have done it myself. This post will explore the tools you have at your disposal, and go through a case study of what one such effort looked like.


Before we discuss strategy & tactics, I will lay out some basic principles that underlie much of this post.

Ideas are Cheap

The chances are, you are not the first person to have your idea.

In a good organization, where people are constantly evaluating options & alternatives and trying to improve the state of the world, it's very likely that the idea you are proposing has already been brought up, considered, and discarded. Someone has already weighed the facts they know, the opinions of their peers, their estimates for costs & benefits, and decided it wasn't worth it.

If you just bring up the same idea in the same context, it will likely not change that person's judgement.

What then?

The thing to realize here is that everything above is mutable: new facts can be presented. Peers can be convinced. New estimates can provided & prototypes can reveal new possibilities.

Ideas are cheap and plentiful, but you often need more than an idea: persuading people to change long held belief is hard work. Having a good idea is just the start of that process.

It's a marathon, not a sprint

Changing people, and the way they work, is a slow process.

Organizations full of people have inertia. Even if you assume that everyone instantly thinks your idea is brilliant, it takes time to change people's existing practices to incorporate a new workflow, or to pull people off projects to launch a new initiative. Work may need to be re-assigned, workflows re-learned, projects postponed or delayed.

And that doesn't include trying to get buy-in on your idea in the first place!

Maybe a small team of 5 people can wrap things up and pivot quickly in a week, but larger organizations of 50 or 100 people can easily takes months to start moving. And that's totally normal!

Just because the "technical" part of your idea can be implemented in a week or a month doesn't mean you should expect an organization to be able to react that quickly. Things take time, and you need to be able to delay gratification and keep pushing for your idea even when any expected "win" is far in the future.

Losing the battle isn't losing the war

You will likely hear a lot of "No"s trying to pitch your idea: maybe you'll get a straight "No", "Maybe"s from people who are really not interested, or "Yes but maybe later" for people who are supportive but not nearly as supportive as you think they should be. Regardless, they all mean the same thing: are not sufficiently convinced.

This is expected. If everyone already thinks your idea is a good one, they would have implemented it themselves already!

As mentioned earlier, there are a lot of ways you can try to push things forward even in the face of a "No". Getting to "no" is just one of many steps in getting to "yes", which is itself just one of many steps to changing how an organization does it's work.

People are people

The last thing to realize, before you start, is that organizations are made up of people: while you may have technical goals or tools or metrics you want to achieve with your changes, changing how things work in an organization is fundamentally a people problem. Technical people may know how to write code, but they aren't really that different from people you find in other walks of life.

Things you should know about people:

Like it or not, this is how people operate. Dealing with people is a different skill than dealing with code, but is one that can similarly be learned, trained and improved upon. You cannot think of the people-stuff as "getting in the way" of whatever technical work you want to do: when dealing with an organization, the people-stuff is the work! It is just another challenge you can try to understand, learn, and make progress with.

Mitigating, or leveraging, these facts of human nature will be a common theme of the rest of this document.

Your Assets

Above, we have discussed the basic principles to keep in mind when driving change across an organization. Now we will consider the various assets you have at your disposal, and how you can make use of them when trying to drive change.

The Idea

While earlier on we said ideas are cheap, they are not totally valueless.

While it is likely someone has already considered your idea and discarded it, it is unlikely that everyone who could be interested, has seriously considered it!

This gives you an opportunity: there are a pool of people who may very well be receptive to your idea right-off-the-bat, without needing any further persuasion. These may not be the "right" people you need to persuade to implement your idea, but they are useful nonetheless:

These are benefits you get "for free" just because you have an idea. You should be sure to make use of them!


The fact of people is that words matter. You need to have the best words.

Whether in person, via email, design documents or project proposals, your words are a chance to get people hyped up about your idea. If you can convince 20% more people to pursue you idea just by shuffling words around, or you can kick off a 6-month proof-of-concept rather than a 1-month proof-of-concept, it makes no sense to waste the opportunity!

Having the best words is something that you can practice, or be trained.

These are table-stakes:


While this article is focused on ideas which you cannot implement yourself, do not discount the asset that you yourself are in pushing ideas forward:

You cannot do everything, but you can often do something. Sometimes just quietly pushing things along yourself gets you what you want faster than trying to argue for headcount up-front, and can put your idea in a better state to argue for headcount after (e.g. you've put together a proof-of-concept to demonstrate the value).

Be extremely conscious of the limits of what you can do yourself, but be willing to "just do it" strategically if you think it's the fastest way to get your idea into a place you want it to be.


Hopefully, you are in organization with nice people. That means that you can often ask things of people even if you have no authority over them nor are you offering anything in return:

Fundamentally, altruistic help is based on social relationships: you are calling upon someone to help you not because they want to, or need to, but purely because they know you are a nice person and are willing to help you out. Or perhaps you've helped them in the past, and they're willing to pay back the favor.

Building these relationships with people literally gives you manpower you can then direct towards making your idea a reality. It's not a huge amount of manpower - you probably won't be able to take more than a handful of hours a week, since these people still have their primary jobs - but it's not nothing.


More powerful than altruism is rational self-interest. While people's altruism is finite, their self-interest is unlimited.

If you can convince someone that helping you directly helps themselves, you're likely to be able to ask far more of them than if you relied on altruism. The more immediate the benefit, the better.

For example, consider these two pitches:

  1. "You need to help us extract your code out of the monolith into a separate module to improve the health of our codebase"

  2. "If you help us extract your code out of the monolith into a separate module, your compile times will drop from 60s to 10s and your Jenkins CI time from 60min to 10min"

  3. "If you extract your code out of the monolith into a separate module, it will speed up time-to-interactivity on the web pages your team owns by 400ms, making the experience much better for your users."

It might take some work up-front to make the second or third pitches a reality: in the above examples, you may need to implement per-module compilation & testing, or per-module Javascript delivery, even without any modular code to take advantage of these features.

Nevertheless, allowing modular compiles/JS-delivery may be easier than modularizing everyone's code. By tilting the incentives slightly, you can make it so that the other person finds it in their self-interest to do the hard work you want them to do, even without formal authority.

New Facts

The last tool you have at your disposal, is the introduction of new Facts.

Earlier on, I had mentioned that one reason ideas are cheap is that they have probably already been considered, and rejected, base on the facts at hand.

Re-introducing the idea to the same people won't change the rejection. But introducing new facts could.

New facts could include:

Bringing new facts to the table is a lot of work: running surveys, bringing in outside expert opinions, and especially doing proof-of-concept work or building prototypes. None of these are easy, and can easily take weeks or months of slogging away to find out something new. However, if you think the reason someone is dubious of your idea is due to the facts available to them, introducing new facts can quickly change their internal calculus of whether it's a good idea or not.


Planning for Momentum

Momentum is when a project keeps moving seemingly on it's own accord: there is progress, people perceive benefit, more effort goes in, and more progress results.

The converse is also true: if a project isn't moving, nobody sees benefit, no effort goes in, and nothing happens.

How do you get from one to the other?

The basic principle behind building momentum is you need to make sure there is a feedback loop between the effort going in, resulting in perceived benefit that justifies more effort.

You often have a choice of how to organize a project: whether as a long effort followed by big reward, or a long effort with incremental rewards. If at all possible, as long as it gets you to the same end-state, you should plan for the latter: this is what ensures that (often short-sighted) rational self interest kicks in and people are willing to help for the immediate, short-term win.

Basically every asset described above feeds upon each other:

The basic approach to getting momentum is planning the work to ensure that the feedback loop exists, and then leveraging whatever assets you have to begin with to give the project a push. You may have to argue for your own time, call in favors from friends, prepare your best pitches & rhetoric to try and convince people, all to try and catch the positive cycle where people start seeing benefit, and the project can begin coasting on its own (partial) success.

Get qualified, falsifiable "No"s

When someone says "No" to your idea, whether directly or indirectly, you should try to get a commitment from them: exactly what would it take to get them to say "Yes"?

The goal of this is two-fold:

You want your "No"s to be qualified and falsifiable: it should always be "No because Y, but if you can provide X, then i'll be ok".

People almost always have some good reason for saying "No". They may have difficulty expressing exactly why they are a "No", but it is your responsibility to try and fish it out of them so you can understand their concerns. Asking for a concrete deliverable that can change their mind is a great way of forcing them to think clearly about what their concerns are and how they can be resolved, so you resolve them and win the person over.

Count every individual

When pushing for an idea, as much as possible you should know what every individual who has a say in the change, regardless of how small, thinks of it:

Knowing these facts for each individual helps you piece together a picture of what the lay of the land is:

These are questions which you simply cannot answer by thinking hard in isolation: you have to go and talk to each individual to collect the facts. Even so, it shouldn't take too long to talk to a few dozen people to piece together an understanding of where everyone stands and what it would take to win each person over.

Count every win

Just as easily as counting people, is to count wins: both historical, and potential.

The exact benefits could vary as widely as the idea itself: maybe some workflow is faster? Engineers happier? Lower defect rate? Lower hosting costs? Greater ease of implementing features? Less engineering spent on tedious/repetitive tasks? Happy customers?

What matters here is that you can give concrete responses to the above questions: answers that someone who isn't already convinced can understand and appreciate. e.g.

More often than not, someone asking you these questions isn't convinced that your idea is a good idea: they don't understand why you want to do this, or why you are already doing this, or what's in it for them. You need to be able to translate your idea into a language that they can understand, so they can support your idea not out of altruism or friendship, but instead out of rational self-interest.

Bootstrapping consensus

One paradox of human nature is that consensus is circular: an individual finds it easiest to believe the current consensus, and the current consensus is made up of what every individual believes.

That can be a problem if the current consensus is that your idea is a bad idea!

If you call a big meeting to try and convince people, everyone will be implicitly glancing around at their peers as they form their own opinion. Even if an individual is starting to come around to your idea, it is more difficult for them to break ranks and say so in front of their un-convinced peers.

If you have an explicitly leadership position, you can use that to push your idea more forcefully, but an individual contributor does not have that luxury.

The way around this problem is to change consensus one individual at a time: find people who you think may be interested, and pitch your idea to them to see if they bite. If they're not interested, move on. If they are, bring the interested individuals together. At this point you have an interest group of people who support your idea. This means:

Even if you don't have everyone on board with your idea, and don't have the key decision makers, you're idea now has some momentum. You can invest that momentum in the assets described earlier: gradually disseminating the idea further, polishing the pitch, trying to get more people involved via self-interest, and running proof-of-concept projects to bring in new facts that demonstrate the idea's viability.

From there, you can slowly and iteratively grow your base of support.

Hopefully you'll eventually get most people, perhaps including the important decision makers, interested. That is the point to call a big meeting - or send out a wide email, to use the circular nature of consensus in your favor:

And at that point, you have successfully formed a new consensus that you can use to push your idea forward!

Case Study: Selenium

To tie everything down to concrete examples, I will discuss a project I helped drive forward fresh out of school.

The basic idea here was I wanted everyone (i.e. the engineering organization) to start using selenium integration tests to start guarding against regressions in our website. The technical side of that project is outside the scope of this post, but the way the project played out illustrates many of the points in this post.

The basic timeline was a follows:

October 2013

Data loss bug causes huge scramble within the company. Legal was involved, PR was involved. Thousands of apology emails sent. Was not a great day.

We were spending huge amounts of time doing manual testing clicking-around our website as we made changes to try and catch regressions. The data-loss-bug path actually was manually tested, but due to time pressure (There was a lot of stuff to click around!) it was not tested sufficiently thoroughly to notice something was wrong. It was just one of many bugs that would slip through our manual QA every week.

This could have been prevented by selenium integration tests.

Unsurprisingly, I was not the first person to have such an idea! We already had a selenium integration test suite, but it wasn't very good: slow, flaky, impossible to iterate on or debug, resulting in nobody writing new tests to cover the ever-growing product footprint.

Everyone agreed that we should have a good integration test suite. I did not manage to convince management that "now" is the time to invest effort in making it good, due to competing priorities for rolling out new features.

November 2013

In between feature work, I did a small proof-of-concept that demonstrated selenium integration tests did not need to be flaky, or hard to work with. The demo was showing how a single laptop could click around the website 4 times in parallel. This could potentially save us a lot of time and effort doing manual QA, and would probably catch more bugs too!

It would have taken more time productionize: so it would be useful to other people, and run on other places that were not just my laptop, and test things that were not what I was working on right-that-moment. Perhaps a month or two of work by one or two people.

My team-mates were impressed - Selenium was no longer a hypothetical, but something they could see would save time and improve quality - and were starting to come over that this was a good idea that should happen sooner rather than later. Regardless, I did not manage to convince leadership enough that we should invest the time now.

December 2013

December is always a slow month with some people on vacation for varying lengths of time. It was even slower for me because I didn't take any vacation over Christmas (I was saving it for Chinese New Year in February 2014). This gave me perhaps 1-2 weeks of December un-committed: I used that time to further flesh out the Selenium proof-of-concept.

My main work in December was to port all the old Selenium tests - the slow, flaky, impossible-to-debug ones, over the the new setup that I had used for the demo so far. There were maybe 60 tests in all. They were still slow, flaky, and hard to debug, but orders of magnitude less so than the existing suite.

Exactly what I did, from a technical point of view, to make the Selenium tests less slow/flaky/impossible-to-debug is an interesting discussion in it's own right that is beyond the scope of this post.

When the office starting filling up again in January, I again pitched the idea of investing the effort fully fleshing these out, but again was turned down: we had a big product launch in March that took 110% priority. After that, perhaps, we could consider it.

January-February 2014

During this time, my Selenium effort was mostly on the back burner.

I called a few meetings with managers/leads on other teams that may be interested to discuss the Selenium project. The response was overwhelmingly negative:

The main concerns were reliability and usability: my colleagues knew from their prior experience that Selenium was terribly flaky, and writing/debugging tests was terribly complex. While I could say that "this time it's different", nobody was convinced.

Another thing that was happening during this time was the accounting of failures: for each bug that slipped through to production (and there were many!) what could have prevented them? We made sure to put "Selenium tests" on each bug that they would apply to, to keep them front-of-mind and make sure anyone who asked "why are we writing such buggy code" would come to their own conclusion "we need selenium tests".

March 2014

The big product launch date came, and was pushed back. The new launch date was in April. No time to work on Selenium tests now!

At this point, we were probably working at 150% cadence on the upcoming product launch: people were staying at work into the evenings, and Sunday work-parties were a thing. This was clearly not sustainable in the long term, but as a short-term push to make the product launch, it worked out OK over-all. No Selenium work went on during this time.

April 2014

The big product launch happened. I had spent 9am to 11pm the Saturday before in the office grinding out the last bits of polish. Fancy product demos were released, media coverage, everything went well. Many engineers took days to a week of time off following the launch to de-compress. There were no clear deadlines or roadmap for a while: the previous plans had only been made up to the big product launch, which was now over, and contingency plans for post-launch fire-fighting which thankfully didn't end up being used. It would take time for people to get organized and decide what would happen next.

I took this chance to declare that I was going to work on Selenium tests. This was a statement of fact, not a request for permission.

In the chaotic aftermath of the launch, I managed to pull in 2-3 other interested individuals to start working on Selenium Tests full time.

May-June 2014

These two months were mostly execution: the 3-4 of us needed to demonstrate to people that their concerns about Selenium test flakiness and complexity have been mitigated.

A lot of very interesting technical work went into this to make the Selenium tests great again, but that's outside the scope of this post.

July 2014

At this point we were pretty confident that what we had was a good thing: our new selenium test suite was catching several bugs a week that no other test suite caught, with 80-90% stability (i.e. 10-20% flaky failures). Because nobody else trusted the selenium suite yet, we took it upon ourselves to take turns watching it: investigating it if it turned red, and triaging a fix if a real regression was found.

In July we also started getting other teams involved in the Selenium project: apart from sending bugs their way if we caught something, we also would pair-program with individuals to teach them how to write selenium tests, and give tech talks to introduce Selenium to a wider audience. This would help spread the knowledge that selenium tests didn't need to be hard to write or debug.

Lastly, we spent the July tallying up the additional bugs that our Selenium suite had caught that no other suite had caught; it added up to a list of maybe 30 bugs over the course of July, 5-6 of which would classify as "emergencies".

August 2014

At this point, we finally sent out the email to create a consensus. This email contained:

By this time we already knew that many people already supported the idea of treating our new selenium test suite seriously: they were already writing tests for their own features, paying attention to the tests if they break, and getting a lot of value from the increase in product quality & iteration speed that Selenium was giving them.

However, we needed to create this consensus for the future:

The important thing to realize at this point is that there wasn't any debate: the debate had already happened one-on-one, person by person, in the weeks preceding. The sole purpose of this broadcast was to lock in all those wins, and to make sure that everyone knew that everyone else supported this project.

And from that, we now had broad consensus that the Selenium suite was an institution that is, and will remain, a core part of our engineering organization.


Changing things in an organization takes time.

Even a simple thing, like getting people to start writing Selenium tests and taking them seriously, is a long slog to get institutionalized: much longer than it takes to "just write code". Nevertheless, the process was entirely reasonable: we did need to get that product launch done, people did have good reason to doubt that Selenium tests were a good idea. When the goal isn't "I want to change how I work" but "I want to change how everyone works", it is expected that it will take a bit longer.

While I dove deep into the Selenium test project, the same principles and tactics often apply regardless of what organizational change you are trying to accomplish as an individual contributor.

This blog post has gone through a lot of the principles and tactics you can use when you try to drive change across an organization. While some things are easier to do if you are a "big shot" manager or director, it is still possible even for individual contributors: you just have to think extra-carefully about what assets you have, and how you can bootstrap your idea to gain momentum and acceptance across the org.

The flip side of changing an organization, rather than just changing code, is that these things last: the number of Selenium tests grew from 60 to thousands. People came and went, teams were broken up and re-formed, entire product verticals were spun up or discarded. Through it all, the Selenium tests and the culture around them remains.

          || Selenium |
          || Tests    |
        _ ||_   _                       _   _   _
       | |_| |_| |                     | |_| |_| |
       |         |                     |         |
       |         |  _   _   _   _   _  |         |
       |         |_| |_| |_| |_| |_| |_|         |
       |         |                     |         |
       |         |       _______       |         |
       |         |      |   |   |      |         |
       |         |      |   |   |      |         |
       |         |      |   |   |      |         |  
   O   |         |      |   |   |      |         |       
  \|/        guarding against web breakages     o           
                   since summer 2014            | 
                                      \/       \|/
           \/          ?                 
     \/               \|/                           \/

About the Author: Haoyi is a software engineer, and the author of many open-source Scala tools such as the Ammonite REPL and the Mill Build Tool. If you enjoyed the contents on this blog, you may also enjoy Haoyi's book Hands-on Scala Programming

uJson: fast, flexible and intuitive JSON for ScalaZero-Overhead Tree Processing with the Visitor Pattern