Rescue & Scale
Web App Performance Optimization
We diagnose and fix performance problems in real-world web apps—slow LCP, heavy bundles, sluggish interactions, and data fetching bottlenecks that hurt conversion and SEO.
Overview
What this service is
This is a hands-on performance service: we profile your app, identify bottlenecks, and implement changes that improve perceived and measured speed.
Work typically includes bundle reduction, rendering fixes, image and font strategy, caching improvements, and removal of unnecessary client-side work.
You get a clear report of what changed and why, plus guardrails to help prevent performance regressions after deployment.
Benefits
What you get
Improved Core Web Vitals
Measurable LCP/INP improvements that support SEO and conversion.
Faster time-to-interactive
Reduce long main-thread tasks and heavy hydration work on first load.
Lower bounce rates on mobile
Performance work focused on real devices and typical network conditions.
Lean bundles and fewer regressions
Code splitting and dependency trimming so the app stays fast as features grow.
Better caching and data strategy
Smarter fetching and caching patterns that reduce repeated network work.
Actionable documentation
A fix log and recommendations your team can apply to future work.
Features
What we deliver
Performance audit + profiling
Lighthouse/WebPageTest profiling, bundle analysis, and bottleneck identification across key routes.
Bundle and dependency reduction
Remove bloat, split heavy code, and reduce third-party impact for quicker loads.
Rendering and hydration fixes
Reduce unnecessary client components and re-renders that cause jank and slow interactions.
Image, font, and asset strategy
Optimise images, fonts, and caching headers for faster rendering and less layout shift.
Caching and data fetching improvements
Tune API calls and caching behaviour to reduce repeated network work and improve responsiveness.
Regression guardrails
Monitoring hooks and practical guidelines to keep performance improvements from slipping back.
Process
How we work
Audit
We profile key routes, collect bottlenecks, and agree on a prioritised fix list.
Plan
We map quick wins vs deeper refactors and align on what moves metrics fastest.
Implement
We apply performance improvements in batches with before/after measurements and PR notes.
Verify
We re-test metrics and validate user journeys on real devices and typical networks.
Handoff
You get a fix report and guardrails so future changes keep performance in check.
Tech Stack
Technologies we use
Core
Tools
Services
Use Cases
Who this is for
Marketing site feels slow on mobile
Improve LCP and reduce JS work so paid traffic doesn’t bounce before seeing value.
Dashboard interactions are sluggish
Fix expensive renders and data patterns that make tables and filters feel heavy.
Bundle size exploded over time
Trim dependencies, split code, and reduce third-party load to regain speed.
Core Web Vitals dipped after a redesign
Identify what changed and implement targeted fixes without reverting UX improvements.
Next.js upgrade or routing migration
Tune performance during App Router migration or framework upgrades to avoid production regressions.
FAQ
Frequently asked questions
Scores vary by environment and page complexity, but we focus on measurable improvements and user-impacting metrics like LCP/INP with clear before/after evidence.
Yes. Asset strategy is often one of the biggest wins, especially for LCP and layout stability.
Yes. We tune client/server boundaries, caching, and rendering strategy in ways that fit modern Next.js patterns.
Yes. We audit and replace or delay non-critical scripts while keeping analytics and business tracking intact.
Yes. You get a summary of changes, the rationale, and recommendations for preventing regressions.
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Regional
Delivery considerations for your region
Compliance & Data (Canada)
For Canadian teams, we focus on practical privacy and security: least-privilege access, clear boundaries, and reviewable operational controls.
We can align implementation with SOC 2 / ISO-friendly practices (without claiming certification) and support documented data flows.
- SOC 2 / ISO-friendly patterns (no certification claims)
- Least-privilege access and secure session handling
- Retention/deletion and export flows where required
- PII-safe logging + access boundary documentation
- NDA and vendor onboarding docs on request
Timezone & Collaboration (North America)
We work with Canadian teams with North America overlap and meeting windows that fit your schedule.
Delivery stays predictable via weekly milestones, async updates, and clearly documented decisions.
- North America overlap and responsive communication
- Async-first updates with written scope decisions
- Weekly milestone demos and progress checkpoints
- Clear escalation path for blockers
- Tight change control with clear sign-offs
Engagement & Procurement (Canada)
We support procurement-friendly delivery: clear scope, change control, and billing cadence aligned to milestones when appropriate.
We can invoice in CAD for CAD-based engagements where required.
- CAD-based engagements and invoicing options
- Milestone-based billing and scope sign-offs
- Time-and-materials for evolving requirements
- Vendor onboarding pack on request
- Optional paid discovery to de-risk delivery
Security & Quality (North America)
We keep quality visible: clean PRs, reviewable changes, and test coverage that matches the risk of each feature.
Performance budgets and release discipline help maintain stability as the product scales.
- CI-friendly testing: unit + integration + smoke tests
- Performance budgets + bundle checks
- Structured release notes + rollback-safe deployments
- Security checklist for auth, roles, and data flows
- Observability hooks (logs + error tracking) ready for production
Want faster pages and better Core Web Vitals?
Send a few slow URLs and your stack. We’ll audit, prioritise fixes, and implement the highest-impact improvements first.
Audit notes + fix report included.