This study by Annie Vella and Kelly Blincoe of the University of Auckland examines how professional software engineers perceive the effects of AI coding assistants on their work, prioritising lived experience over tool performance. It argues that most prior evidence is cross-sectional, short-term, benchmark-based or drawn from students, and that productivity and developer experience have usually been studied in isolation, so it tracks the same professionals over time and treats the two jointly.

The authors ran two online questionnaires six months apart — in October 2024 and April 2025 — yielding 158 eligible participants at the first time point, 101 at the second and a matched longitudinal cohort of 95, drawn from 28 countries with the largest share in New Zealand. The design was convergent parallel mixed methods: Likert-scale items on task focus across six development tasks, the three dimensions of the DevEx framework (feedback loops, cognitive load and flow state) and perceived productivity were analysed with non-parametric tests, and open-ended responses were analysed with reflexive thematic analysis.

Key Points

  • Most participants perceived spending less time on the development tasks measured; writing code showed the steepest decline, with 82% reporting less time on it by the second questionnaire. Reviewing code was the only task whose mean sat above neutral at both time points.
  • Among matched participants, the balance between verification tasks (reviewing, testing, debugging) and creation tasks (designing, writing, refactoring) shifted significantly toward verification, although neither group changed significantly on its own; the authors call this the Creation-to-Verification Shift.
  • Because the measured increase in verification was modest, the authors propose that the freed effort flows into Supervisory Engineering Work — directing AI, evaluating its output and correcting its errors — a category they argue traditional SDLC taxonomies do not capture.
  • Perceived productivity was high and stable (84% reporting improvement at both time points, 77% of matched participants giving identical ratings), while the share reporting worsened developer experience in at least one dimension nearly doubled from 14% to 27%. Feedback loops improved significantly; cognitive load and flow state showed non-significant declines. The authors term this the Productivity-Experience Paradox.
  • Changes in developer experience did not correlate with changes in productivity, in contrast to moderate-to-strong cross-sectional correlations between the two at each time point.
  • The tool landscape shifted during the study: 82% of matched participants changed their tool combinations, the mean number of tools per participant rose from 1.9 to 2.9, ChatGPT usage fell from 70% to 58% and Cursor usage rose from 16% to 29%.
  • Maintainability was the only concern whose ranking changed significantly, rising from 3% to 19% of participants’ primary concern; quality remained the dominant primary concern.

Notes

The authors acknowledge several limitations. Forty percent of first-questionnaire participants did not complete the second, and engineers who became disillusioned may have been less likely to respond. Only engineers currently using AI coding assistants were sampled, so the 84% productivity figure should be read as 84% of continuing users; 85% of the sample were men and predominantly English-speaking. The measures are perception-based and subject to recall bias, and the findings reflect tools as they existed in late 2024 and early 2025, which may not hold for newer, more autonomous agentic tools. The first author is a practising software engineer, which the authors manage as a potential source of interpretive bias. They disclose using Claude Code to help develop R scripts for statistical analysis and to review the text for clarity.