Situation: A senior ML engineer on my team had been using a complex ensemble of bespoke feature engineering and an older tree-based model for a recommendation system. Our experiments and infra constraints suggested a simpler transformer-based ranking model would improve latency and maintainability, but they were resistant to changing their approach.
Task: I needed to give constructive, actionable feedback that respected their expertise, reduced defensiveness, and led to measurable experimentation toward a better solution.
Action:
- Prepare: I reviewed the code, recent experiment logs, and evaluation metrics. I prepared a short comparison (metrics, latency, infra cost, reproducibility) and identified concrete failure modes of the current approach with examples. I planned a private, time-boxed 1:1 and an agenda: share observations, ask for their perspective, propose experiments, align on criteria for success.
- Language & tone: I used curiosity-first, nonjudgmental language: “I noticed…”, “Can you help me understand…”, “What constraints led you to choose…?” Then I shifted to impact-focused statements: “Because A and B, our inference latency is X and recall is Y; that leads to Z business impact.” I suggested concrete alternatives as experiments, not mandates: “Would you be open to running a controlled A/B comparing the ensemble to a lightweight transformer on a held-out slice?”
- Actionable requests: I proposed a clear experiment plan with success criteria (metric lift, latency threshold, infra cost), timeline (2 sprints), and required resources. I volunteered to pair on implementation and to help with baseline reproducibility.
- Follow-up: We documented the experiment in the team tracker, scheduled short weekly syncs to unblock issues, and agreed on decision rules (if metric improves by ≥1% and latency < target, proceed to rollout). After results, I gave balanced feedback highlighting positives and next steps, and suggested knowledge-sharing sessions.
Result: The collaborative, evidence-focused approach reduced defensiveness, produced two quick experiments within the agreed timeframe, and led to a simpler model that met latency and accuracy goals. The senior engineer retained ownership of the work and later advocated for the new approach.
What I learned: For senior peers, respect and data matter most—ask questions, suggest experiments, provide resources, and set clear, mutually agreed decision criteria to drive adoption.