Case Study: Cutting Build Times 3× — SSR, Caching, and Developer Experience Improvements

Case Study: Cutting Build Times 3× — SSR, Caching, and Developer Experience Improvements

Hook: Faster builds mean faster feedback loops and happier engineers. This case study shows how we identified bottlenecks, applied targeted improvements (SSR adjustments, caching, local testing), and measured gains.

Starting point and goals

Our monorepo served multiple apps. CI builds took 45+ minutes and local iteration was painful. Goals:

• Bring CI build times under 10 minutes for critical pipelines.
• Reduce local rebuilds and improve dev onboarding.
• Improve deploy confidence through better smoke tests and previews.

What we changed — technical steps

1. Split pipelines: Separate PR builds into tests, linting, and artifact builds so unrelated changes don't retrigger full builds.
2. Incremental SSR and cache strategies: Move stable routes to build-time prerendering and use edge SSR for dynamic, authenticated paths. We followed SSR best practices similar to these reference notes: SSR strategies for JavaScript shops.
3. Remote preview environments: Adopted hosted tunnels and ephemeral environments for faster QA against realistic backends; see roundups for hosted tunnels that informed our vendor selection: Roundup Review: Hosted Tunnels and Local Testing Platforms.
4. Monorepo cache and artifact sharing: Aggressive caching for node modules and compiled assets across CI nodes.

Developer experience moves

We put major emphasis on reducing cognitive load:

• One-command local dev (shell script + dev containers).
• Documented common workflows with short videos and a troubleshooting FAQ.
• Quick feedback loops via preview links for feature branches so product and QA can test without complex local setup.

Measurement and telemetry

We instrumented three signals:

1. CI median and P95 build time.
2. Local cold start time for new contributors.
3. Time between commit and deploy to staging.

Within three months median CI time fell from 45 to 12 minutes; P95 dropped below 20 minutes. Local cold-start for new contributors fell from 2 hours to 30 minutes.

Organizational practices that mattered

• Weekly DX (developer experience) review with actionable tickets.
• Postmortems for long-running builds and flaky tests.
• Small, measurable improvement targets rather than big-bang rewrites.

Vendor choices and tradeoffs

Choosing hosted previews and tunnels required balancing security and cost. We evaluated options using comparative reviews and local-testing roundups — the vendor reviews we consulted guided our decision: Hosted Tunnels & Local Testing Roundup.

Recommended checklist for teams

1. Audit your pipelines and split independent concerns.
2. Adopt caching for dependencies and build artifacts.
3. Use remote previews to remove environment setup friction.
4. Measure, iterate, and tie improvements to onboarding KPIs.

Closing and follow-ups

Improvements compound. Small investments in caching, pipeline hygiene, and preview tooling turned into a threefold improvement in developer throughput for us — and freed time for feature work.

Further reading:

• SSR strategies for JavaScript shops
• Hosted tunnels and local testing roundups
• Design clear architecture diagrams