01
No surprises in production
Every change ships behind a feature flag and through a staging mirror. We do not deploy on Fridays. We do not push to production for the first time on a launch day.
Web platforms · since 2014
Boring tools, shipped quietly, kept up for years.
CoreDevStructure is a five-engineer studio in Sarrià-Sant Gervasi. We build performant marketing sites, application platforms, and headless commerce engines for European clients — and stay on to maintain them.
DOC. ID
CDS-IDX-001
- REV
- 7.4
- STATUS
- in production
- LAST REVIEW
- 2026-06-12
- TARGET
- production_eu_west_1
- AUTHOR
- S. Bonastre
Latency budget · 1,000 ms
Click a segment to read how we tune it.A page has roughly one second of patience. Here is how we spend it.
DNS lookup
We park your domain on Cloudflare, take the median DNS lookup down to single-digit milliseconds, and never wait for an upstream nameserver.
§ 01
Operating principles
CDS-PRINCIPLES.md
Six rules we hold to.
02
Performance is a feature
Every brief gets a measured budget — JS payload, LCP target, p75 latency. The budget is enforced in the pull-request CI, not by good intentions.
03
Tests where they matter
We test the seams — the authentication flow, the billing integration, the data import. We do not chase 100% coverage on a function that returns a string.
04
Code that reads like a memo
Naming is a contract. Every variable, function, and module is named for the next engineer reading it on a Tuesday morning at 09:00.
05
One way to do each thing
Convention over configuration. Three forms of validation in one codebase is two forms too many. We pick one and document why.
06
No abandoned dependencies
Every retainer includes a quarterly upgrade walk where we remove what we no longer use and patch what we do. Yesterday's dependency is tomorrow's incident.
§ 02
Capabilities
CAP-01 → CAP-06
Six lines of work, written down.
01
CAP-01
Storefronts that don't look like Shopify
Headless commerce
Storefronts built on Shopify Hydrogen, Saleor, or BigCommerce — paired with a custom front end you actually own.
Shopify Hydrogen
Saleor
Next.js
TypeScript
Cloudflare Workers
02
CAP-02
Internal tools, dashboards, B2B SaaS
Application platforms
Custom web applications with the boring parts done well — auth, billing, audit logs, role-based access.
Next.js
Remix
Postgres
Prisma
tRPC
Stripe
03
CAP-03
REST, GraphQL, integrations
API engineering
Public and private APIs that age well — properly versioned, properly documented, properly rate limited.
OpenAPI 3.1
Hono
Fastify
GraphQL Yoga
PostgREST
04
CAP-04
Core Web Vitals + edge
Performance engineering
Get your Lighthouse score above 95, your LCP under 1.0 second, and keep them there.
Lighthouse CI
Web Vitals API
Cloudflare Workers
Vercel Edge
05
CAP-05
Framework / CMS migrations · no SEO loss
Re-platforming
Move from WordPress, Drupal, or a creaky bespoke stack to something maintainable — without losing rankings or breaking links.
Next.js
Astro
Sanity
Storyblok
Cloudflare DNS
06
CAP-06
Architecture · security · accessibility
Engineering audits
A second pair of eyes on a code base, with a written report you can hand to your board.
Static analysis
OWASP ZAP
axe-core
Lighthouse
Snyk
§ 03
Selected engagements
ENG-014 / 022 / 035
Three engagements, three sectors.
CDS-ENG-014 DTC food · Penedès Headless commerce migration
Oliva del Penedès
A 32-year-old olive-oil cooperative selling direct to homes across France, Germany, and the Nordics — on a Magento install nobody at the co-op could maintain.
"We had a beautiful product on a website that loaded in eight seconds. Now it loads in seven hundred milliseconds and the orders take care of themselves."
Stack Shopify Hydrogen · Cloudflare · Sanity · Stripe Tax
CDS-ENG-018 Independent media · Catalonia Performance engineering
Telecat Online
A regional news outlet on Drupal 7, slow on mobile, losing readers to faster competitors. We rebuilt the front end on Astro without touching the back office.
"They built us a front end that talks to our old CMS and feels like a different decade. Same editors, same workflow, faster paper."
Stack Astro · Drupal JSON:API · Cloudflare · Plausible
CDS-ENG-022 B2B SaaS · operations Application platform · v1.0
Quadram Inventory
A founding team of two with a working spreadsheet and a paying pilot customer. We turned the spreadsheet into an inventory platform — auth, multi-tenant data, billing, dashboards.
"They shipped the parts of the product I dreaded. Auth, billing, admin. We could focus on the customer-facing pages."
Stack Next.js · Postgres · Prisma · tRPC · Stripe Billing
§ 04
Stack we ship
CDS-BOM.lock
A bill of materials, not a hype reel.
These are the boring tools we choose on purpose. Most of them are at least three major versions old. None of them are leaving the kit this year.
Frontend
Next.js 15 · Astro 4 · Remix · React 19 · TypeScript 5.5
Styling
CSS variables · vanilla-extract · Panda CSS · Tailwind (where it earns its keep)
Backend
Node.js 22 · Hono · Fastify · tRPC 11 · GraphQL Yoga
Data
Postgres 16 · Prisma · Drizzle · Redis · DuckDB
Infrastructure
Cloudflare Workers · Vercel · Hetzner · Fly.io · Terraform
Observability
Sentry · OpenTelemetry · Grafana Cloud · Logtail · BetterStack
CMS · Commerce
Sanity · Storyblok · Shopify Hydrogen · Saleor · Stripe
Testing · CI
Playwright · Vitest · GitHub Actions · Lighthouse CI · axe-core
§ 05
Studio in figures
CDS-METRICS-Q1
Years in practice
11
Engagements shipped
40+
Median LCP, p75
< 1.0 s
Production uptime SLA
99.95%
§ 06
Notes from clients
CDS-NPS.txt
What clients say after launch.
They diagnosed in two weeks what our previous agency had refused to look at for two years. The follow-up build came in on time, on budget, and on speed.
Mònica Galí
CTO · Oliva del Penedès
Half of what they delivered was code. The other half was a runbook our on-call engineers actually use at three in the morning.
Hugo Mendes
Head of platform · Roteiro
A studio that says no to features without flinching. The product is sharper because of it.
Aina Soler
Co-founder · Quadram Inventory