Environment and technology

Lean bundles, sensible caching, and fewer round trips reduce cost and carbon at the same time. We profile early and cut work that does not serve users — especially on mobile networks where every megabyte counts twice.

• Budgets for JS payload and image weight, checked in CI where it helps.
• Prefer static generation and edge caching for read-heavy surfaces.
• Defer third-party tags until you know they earn their keep.

Faster pages are often greener pages — users get a better experience at the same time.

Region selection, autoscaling policies, and batching jobs matter more than slogans. We document assumptions, measure where we can, and revisit them as traffic grows so “green” decisions stay accountable.

• Match regions to users; avoid cross-region chatter by default.
• Right-size workloads; autoscale with sane floors and ceilings.
• Batch heavy jobs off peak when the grid and pricing align.

The greenest line of code is one you do not rewrite every year. We favour boring stacks, clear boundaries, and documentation so systems live longer and retire gracefully instead of rotting in place.

Sustainability in engineering is partly “how long does this codebase stay healthy without a rewrite?”

• Conventions over one-off frameworks per team.
• Ownership maps so legacy does not become “nobody’s problem”.
• Retirement plans for services, not only launch plans.