Lessons In Writing Effective Performance Evaluations That You Should Never Forget

In the fast-paced world of software development, it‘s easy to get so caught up in the day-to-day grind of coding, testing, and shipping that we neglect one of our most crucial responsibilities as engineering leaders: Developing our people.

Providing regular, constructive performance feedback is essential for helping developers learn, grow, and reach their full potential. Research has consistently shown that developers who receive effective feedback are more engaged, productive, and likely to stick around. A study by Gallup found that employees who receive regular, meaningful feedback are 3.5 times more likely to be engaged at work compared to those who don‘t.^1

But let‘s be real – writing performance evaluations is hard. It‘s time-consuming, emotionally draining, and often awkward. Many managers fall into the trap of treating it as a box-checking exercise, recycling the same tired cliches year after year.

As an engineering leader and a full-stack developer myself, I‘ve certainly been guilty of this. In my early days as a manager, my feedback was often vague and generic, focusing more on personality traits than concrete outcomes.

But over time, through trial and error and lots of research, I‘ve come to realize that writing effective performance evaluations is both an art and a science. It requires a deep understanding of what drives developer performance, a commitment to continuous improvement, and a whole lot of emotional intelligence.

Here are some of the most important lessons I‘ve learned over the years about writing performance reviews that truly help developers excel.

Set Clear Expectations From the Start

One of the biggest mistakes managers make is waiting until the end of the year to set expectations. By then, it‘s too late. Effective performance management starts with setting clear, measurable goals at the outset of the performance cycle.

For developers, this means defining specific technical competencies and targets. What skills do you expect them to master? What code quality standards should they uphold? How many story points should they aim to complete each sprint?

Consider this real example of developer goals from Google‘s engineering ladder[^2]:

Level	Technical Skills	Impact
Software Engineer I	Consistently write clean, safe code. Learn to create more complex components.	Complete small features independently. Contribute to designs for larger projects.
Software Engineer II	Design and implement medium to large features. Identify best practices and promote to wider team.	Lead the design and implementation of projects spanning multiple sprints. Have production impact across multiple teams/products.

Notice how these expectations are specific, measurable, and tailored to the developer‘s level. They give both the manager and the developer a clear north star to work towards.

Of course, technical skills are just one piece of the puzzle. It‘s equally important to set expectations around soft skills like communication, collaboration, and problem-solving. These are often the make-or-break factors in a developer‘s success.

Some examples of soft skill expectations you might set:

• Proactively communicates status, blockers, and risks to stakeholders
• Collaborates cross-functionally to gather requirements and align on solutions
• Mentors junior developers through code reviews and pairing sessions
• Demonstrates creativity and grit in tackling complex bugs

The key is to make these expectations crystal clear from the start, then regularly check in on progress throughout the year. That way, when it comes time to write the formal evaluation, there are no surprises.

Gather Hard Data and Artifacts

Evaluating developer performance is uniquely challenging because so much of the work is intangible. How do you measure the quality of someone‘s code? The elegance of their architecture?

The key is to rely on hard data and artifacts as much as possible. Some examples:

• Code quality metrics (test coverage, cyclomatic complexity, etc.)
• Bug reports and resolution times
• Pull request feedback and iteration cycles
• Sprint velocity and burndown charts
• Peer feedback from code reviews and retrospectives

Consider this example of using code quality data in an evaluation:

"Jane‘s code consistently demonstrates a high level of quality, as evidenced by her average test coverage of 95% (compared to a team average of 80%). She is diligent about refactoring for simplicity and performance, reducing the cyclomatic complexity of the checkout service by 25% last quarter. While she occasionally misses edge cases in her initial implementations (see bug #1234), she is quick to address them and learn from those mistakes."

See how this provides a concrete, data-driven assessment of Jane‘s technical abilities? It‘s far more meaningful than simply saying "Jane is a strong coder."

Of course, metrics only tell part of the story. It‘s equally important to gather qualitative feedback from peers, stakeholders, and end users. Some ways to do this:

• Regular 1:1s with the developer‘s collaborators
• 360-degree feedback surveys
• Project retrospectives and postmortems
• Customer satisfaction scores and user reviews

The goal is to paint a comprehensive picture of the developer‘s impact, not just fixate on a few arbitrary data points.

Recognize the Intangibles

While hard data is crucial, the best engineering leaders also recognize the intangible contributions that set great developers apart. These are the things that are hard to capture in a metric but make a world of difference to team productivity and morale.

Some examples:

• Mentoring and knowledge-sharing with other developers
• Improving engineering processes and best practices
• Advocating for technical excellence and pushing back on shortcuts
• Bringing levity and positivity to the team culture

Consider this snippet of feedback recognizing a developer‘s intangible contributions:

"While Sam‘s individual code output was on par with expectations, where he really shined was in his team collaboration. He took initiative to lead weekly lunch-and-learns on topics like functional programming and unit testing, which dramatically leveled up the skills of our junior developers. He also worked with the DevOps team to streamline our CI/CD pipeline, reducing build times by 30%. Beyond his technical work, Sam is a beacon of positivity on the team, always quick with a joke or word of encouragement when the going gets tough."

Notice how this feedback highlights the value Sam brings beyond just writing code. By spotlighting his impact on team learning, processes, and culture, it paints him as a true force-multiplier.

Deliver Honest, Actionable Feedback

Of course, not all feedback will be glowingly positive. One of the hardest parts of writing performance reviews is delivering constructive criticism when a developer is falling short.

The key is to focus on specific, observable behaviors rather than personal attributes. Instead of saying "You‘re not a team player," pinpoint exact moments when the developer failed to collaborate effectively. Then, offer concrete suggestions for what to do differently.

For example:

"On the Q2 redesign project, there were several instances where you pushed code without first aligning with the team on the approach (see pull requests #123 and #456). This caused delays and rework when the changes didn‘t integrate smoothly. Going forward, I‘d recommend scheduling brief design reviews before starting work on major components. This will ensure everyone is on the same page and can flag integration issues early."

Notice how this feedback is specific, actionable, and delivered with a forward-looking focus. It‘s not about assigning blame, but helping the developer learn and grow.

It‘s also important to balance constructive feedback with recognition of what the developer is doing well. Research shows that a ratio of about 5 positive comments to 1 negative is optimal for driving performance.[^3] So even if a developer is struggling, be sure to call out their strengths and successes too.

Tie to Broader Engineering Goals

Effective performance evaluations don‘t happen in a vacuum. They should be closely tied to the broader goals and priorities of the engineering organization.

Consider how the developer‘s work aligns with the company‘s technical strategy. Are they contributing to the development of key architectural initiatives? Are they helping to drive the adoption of new technologies or methodologies?

For example:

"Jane‘s work on the new microservices architecture has been instrumental in our transition to a more scalable, flexible system. Her deep expertise in Kubernetes and gRPC has helped guide the team through the learning curve and set a high bar for code quality. Thanks to her efforts, we‘re on track to have 90% of our services migrated by Q3, putting us in a strong position to support the company‘s growth targets."

See how this feedback connects Jane‘s individual work to the larger engineering roadmap? It shows that her contributions are not just valuable in isolation, but critical to the success of the business.

Encourage Continuous Improvement

Finally, remember that performance evaluations are not a one-and-done deal. The best engineering organizations foster a culture of continuous feedback and growth.

Encourage your developers to seek out feedback proactively, not just wait for the annual review cycle. Create channels for regular peer feedback, like weekly code reviews or team retrospectives.

And don‘t forget about your own growth as a manager. Writing effective evaluations is a skill that takes practice and reflection. Seek out feedback from your peers and mentors on how you can improve your coaching abilities.

Most importantly, lead by example. Share your own failures and learnings openly. Demonstrate a growth mindset in your own work. The more you model continuous improvement, the more your team will embrace it too.

Conclusion

Writing effective performance evaluations is one of the most high-leverage things you can do as an engineering leader. It‘s a chance to celebrate successes, identify growth opportunities, and chart a course for the future.

But it‘s not easy. It requires a deep understanding of what drives developer performance, a commitment to fairness and objectivity, and a whole lot of emotional intelligence.

By setting clear expectations, gathering data and artifacts, recognizing intangible contributions, delivering honest feedback, tying to broader goals, and encouraging continuous improvement, you can create evaluations that truly help your developers thrive.

It‘s worth the effort. Research consistently shows that developers who receive regular, meaningful feedback are more engaged, productive, and likely to stick around for the long haul.^4

In the words of Kim Scott, author of Radical Candor: "Guidance, encouragement, and feedback are the best gifts you can give to the people who work for you."[^5]

So go forth and write those evaluations. Your developers (and your business) will thank you.

[^2]: Google Engineering Practices Documentation, "Engineering Ladder"
[^3]: Harvard Business Review, "The Ideal Praise-to-Criticism Ratio"

[^5]: Kim Scott, Radical Candor (2017)