Blazity

Blazity is a Next.js performance engineering firm based in Warsaw, Poland. The company positions itself as a Certified Vercel Solution Partner specializing in performance optimization, AI agent development, and migrations from legacy stacks to Next.js. Their work targets enterprise teams operating at traffic scale—companies like Arthur (a financial modeling platform), Planday (workforce management), Vibes (customer engagement), and Encoura (higher education technology). On a CookUnity engagement, Blazity delivered 70% faster interactivity and 28% more conversions after rebuilding the signup funnel to Next.js. The firm has open-sourced three projects: Next-CWV-Monitor (Core Web Vitals tracking), Enterprise-Commerce (a Next.js storefront template), and Next-Enterprise (a boilerplate).

Services and capabilities

Blazity groups its work into five areas. Performance Engineering diagnoses via field data rather than Lighthouse scores alone, then fixes root causes in rendering strategy, caching architecture, and third-party script loading. The firm claims clients see green Core Web Vitals, stable infrastructure under peak traffic, and conversion gains (CookUnity: 28% more conversions, 70% INP improvement). They handle rendering strategy audits across page types—SSR, SSG, ISR, PPR—and configure cache alignment at CDN, ISR, and application layers. A single case study shows 50% INP improvement, 28% conversion increase, and 30x faster deployment cycles after migrating legacy React/Redux to Next.js with server-side rendering.

AI Engineering focuses on production-ready agents rather than POC-stage chatbots. The engagement model includes system design (prompt flows, context retrieval via AI Gateway, durable workflows with pause/resume), delivery of the first agent, optional internal capability transfer through paired coding and documentation, and observability setup. Outcomes stated: 80–95% cost reduction for targeted processes, 10–20x productivity gains. Agents run on Vercel's infrastructure using the AI SDK, Workflows, and Sandbox. One open-source example: a Slack bot monitoring brand visibility across GPT-4o, Claude, Gemini, and Grok simultaneously.

Migration & Modernization covers legacy-to-Next.js migrations (positioned as zero-downtime), headless CMS migrations, and enterprise solution architecture reviews. Application Development includes Next.js platform development and multi-brand, multi-region deployments. Technical Consulting offers audits, modernization strategy sessions, and architecture reviews—billed as "clarity before commitment," with a 12-hour response time.

Each service area includes specific tactical outputs. For performance work: field data diagnosis, rendering audits, Core Web Vitals remediation, caching configuration, third-party script audits, and bundle optimization. For AI agents: ROI and opportunity reports identifying 2–5 candidates, architecture diagrams, one production agent, optional playbook for internal teams, observability dashboards, and runbooks.

Notable work

Three named clients appear with attributed quotes. Arthur's CTO (Zach Fry) credits Blazity with increased annual recurring revenue, excellent project management via a TPM, and knowledgeable engineers. Planday's Director of Growth (Frederic Linfjärd) says the project met timeline and improved performance, "unlocking growth opportunities." Vibes' CTO (Brian Garofola) noted Blazity's strength in frontend specialization; the same executive quotes again: "very happy with the outcomes and look forward to continuing to work with them on larger initiatives."

Encaura's Senior Marketing Director (Andrew Swenson) reports Blazity modernized their marketing website technology, improved performance, and boosted engagement while following agile methodology on time and budget.

One detailed case study (unnamed client): legacy React/Redux signup funnel with poor INP. After migration to Next.js with server-side rendering, results were 50% INP improvement, 28% conversion rate increase, 30x faster deployment cycle, and 70% development speed boost.

How they work

Blazity's engagement model centers on diagnostic clarity followed by implementation. For performance work, the first step is field data diagnosis—measuring real-user experience, not just Lighthouse lab scores. The firm claims field data is typically 30–50% worse than lab scores. Then they map rendering strategy page-by-page, align caching layers, and fix architectural root causes. For AI agents, the process is: system design (architecture document), first agent delivery (fully tested and deployed), optional internal capability transfer (paired coding and playbook), observability setup (dashboards and alerts), and documentation handover (runbooks, prompt guidelines, maintenance instructions).

The firm commits to 12-hour response time on initial contact. Pricing is not disclosed in the source material. No explicit team size, billable rates, or engagement duration is stated.

Team and credentials

Blazity is incorporated as Blazity Sp. z o.o. in Warsaw, Poland. Team size is not disclosed. Named individuals in the source: Jakub Jabłoński (Principal Software Engineer), Hubert Francuz (Head of Delivery). The firm is a Certified Vercel Solution Partner. No other certifications (ISO 27001, SOC 2, HIPAA, etc.), awards, or Clutch/G2 ratings appear in the source material. The firm hosts "The Next Gen Web Podcast," a public podcast featuring engineering talks and industry discussion.