quadevs
Independent dev studio · est. 2016 · the engineer you talk to is the engineer who ships it

Production software for any business niche. Sharpened on healthcare integration, AI agents, and ops platforms where the stakes are highest.

Ten years of shipping. HEDIS pipelines, LLM agents in production, internal platforms that survive Monday morning at 9:01, plus the e-commerce, mobile, and marketing systems that fund the rest. Direct contracts. We work under your BAA.

01Healthcare integrations 02Production AI agents 03Internal ops platforms
prod tail -f · 7d uptime 99.97%

Selected work

Healthcare interop, AI agents, ops platforms, e-commerce and beyond. A featured slice.

Ten years of shipping into production. One of our healthcare clients passed external info-blocking review without remediation. Our HEDIS measurement pipeline reproduces every submission from raw inputs to final measure on demand. We have shipped FHIR R4 platforms, TEFCA QHIN connectors, USCDI v3 mappings, production LLM agents with tool routing, multi-tenant SaaS, e-commerce stacks, marketplaces, native mobile apps, ops dashboards, WordPress fleets, Shopify rollouts, and paid acquisition systems. Most are under NDA, so we describe the shape of the work, not the brand. Names and specifics after a call.

CASE 01 / Healthcare · web

Multi-clinic web platform

Multi-tenant Next.js framework that launches ADA-compliant, HIPAA-aware clinic websites from one shared codebase. Each location gets its own subdomain, branded theme, appointment widgets, and secure intake forms without a separate build per site.

Next.js · headless · Twilio · ADA View case
CASE 02 / Healthcare · interop

FHIR · TEFCA · USCDI integration

Production FHIR R4 server covering 42 resource types, SMART on FHIR v2.1 with PKCE, TEFCA QHIN handshake against Epic Nexus and CommonWell, and a tamper-evident audit chain scoped to the Consent that authorized each read. Passed external info-blocking review without remediation.

FHIR R4 · SMART v2.1 · TEFCA · USCDI v3 · Da Vinci · CARIN BB · US Core View case
CASE 03 / Healthcare · pipeline

HEDIS measurement pipeline

HEDIS measurement pipeline built on .NET Windows services: fax intake, insurance portal sync, document classification, retry queues, and Slack-native incident routing tied to stuck-order diagnostics. HEDIS submissions reproduce on demand from raw inputs to final measure.

.NET · MSSQL · NewRelic · HEDIS View case
CASE 04 / Healthcare · agents

Clinical document watcher

Fleet of .NET clinical document watcher agents running unattended at provider endpoints. Each agent detects signed documents, OCRs where needed, and pushes to a central store with chain-of-custody hashing. Buffers locally on outage and resumes without duplicates.

.NET · OCR · S3 · audit log View case
CASE 05 / AI agents

Tool-use agent · production

Production LLM agent with typed tool catalogs, structured-output validation, per-tenant billing meters, and a reviewer loop that catches bad tool calls before they reach customer-facing systems. Model-provider swap is a config change, not a rewrite.

LLM · TypeScript · Postgres View case
CASE 06 / AI · pipeline

Image classify and OCR pipeline

High-volume image classification and OCR pipeline with GPU-aware batch scheduling and a variable worker pool. Structured clinical data extracts route downstream with content-hash deduplication. Survives bursty load without losing a frame.

Python · GPU workers · S3 View case
CASE 07 / Ops platform

Trading operations terminal

Internal orchestration platform for dozens of trading bots across dozens of servers. Python strategy DSL, parameter validation at admit time, live PnL telemetry over WebSocket, Telegram on-call paging. Monthly turnover in the millions, ops team of one.

Python · WebSocket · Redis · Telegram View case
CASE 08 / Growth · SEO

Healthcare SEO program

Technical SEO program for clinical sites. JSON-LD schema markup for MedicalClinic, Physician, Service, and MedicalProcedure, Core Web Vitals optimization, hreflang for multilingual content, and GSC instrumentation that surfaces ranking drops before they compound.

Next.js · schema.org · GSC · Ahrefs View case
CASE 09 / Growth · SMM

Social production pipeline

Content production pipeline for healthcare and personal brands. Automated cross-platform scheduling, AI-assisted caption reformatting, brand-safety gate before publish, and unified engagement reporting. One creator, many channels, no copy-paste.

Buffer API · OpenGraph · LLM View case
CASE 10 / Automotive · marketplace

Pre-owned car marketplace

Two-sided marketplace for pre-owned cars. Buyer-side Elasticsearch search tuned to category intent, VIN decoding, dealership onboarding, condition reports, financing match, escrow flow, and fraud signals at the listing layer before any inventory goes live.

Next.js · Postgres · ElasticSearch View case
CASE 11 / Healthcare · imaging

Scan and fax image enhancement

Server-side enhancement pipeline for medical document imaging. Deskews, denoises, and normalizes contrast on scans and inbound faxes, then scores OCR readability before any document reaches the clinical record. Persistent failures escalate automatically for human review.

.NET · OCR · imaging · ML View case
CASE 12 / Healthcare · ETL

Document reformat at scale

Memory-bounded streaming pipeline that converts clinical document corpora across PDF, TIFF, DOCX, structured XML, and clinical CDA. Structure survives format hops. Every transformation step writes an audit record with input and output hashes for replay.

Python · streaming · CDA · PDF View case
CASE 13 / Healthcare · mobile

Mobile medication selector

Patient-facing iOS and Android medication selector app built for a real symptomatic moment. Indication search, drug interaction and contraindication checks against the FHIR-backed patient profile, OTC versus Rx routing, and a Mapbox pharmacy locator.

React Native · FHIR · Mapbox View case
CASE 14 / Logistics · ops

International logistics console

Operations console for cross-border freight forwarding built around real domain jargon. Carrier API normalization, customs documentation, route-exception detection, broker handoffs with ownership transfer, and finance reconciliation tied to invoice line items.

Next.js · Postgres · carrier APIs View case
CASE 15 / Web · WordPress

WordPress site fleet

Tens of WordPress builds across realtors, clinics, politicians, retailers, and B2B e-commerce. Custom themes, ACF and Gutenberg block libraries for editors, WCAG 2.2 AA accessibility, and LiteSpeed-tuned hosting under contract. Editors run their own sites.

WordPress · ACF · Gutenberg · LiteSpeed View case
CASE 16 / E-commerce · Shopify

Shopify apps and storefronts

Custom Shopify app development for indie brands and growing retailers. Private apps for back-of-house automation, public App Store apps with OAuth and billing, headless storefronts on Hydrogen, and theme work where it earns its place. Built so the merchant runs the day to day.

Shopify CLI · Polaris · Liquid · Hydrogen View case
CASE 17 / Mobile · iOS, Android

Native and cross-platform mobile apps

Native and cross-platform mobile apps across consumer, healthcare, and enterprise. Offline-first sync, push and live activity, in-app purchases, biometrics, and secure storage. CI signing is wired so App Store and Play Store updates ship without an engineering escalation.

React Native · Swift · Kotlin View case
CASE 18 / Energy · billing

Energy sector billing, Ukraine

Billing and account-management software for regulated energy distributors and retailers. Tariff calculation engine, meter intake from physical and remote channels, multi-channel customer notifications, and regulator-aware reporting integrated with national clearing pipelines.

.NET · MSSQL · regulator APIs View case
CASE 19 / Healthcare · multilingual

Multilingual clinic platform

Multilingual web platform for a private multi-location medical center serving the Eastern European diaspora. i18n routing in Polish, Ukrainian, and Russian, a multi-step appointment wizard wired to an external booking API, and native medical terminology across all locales.

React · Vite · Express · i18next · external booking API View case
CASE 20 / Healthcare · reporting

Automated medical reporting

Branded PDF report generator for clinical workflows. Templated layouts, dynamic chart binding, signature blocks, batch generation against patient cohorts, locale-aware content, and a downstream distribution integration. Replaces hand-built Word documents for ops teams.

.NET · PDF · LeadTools · MSSQL View case
CASE 21 / Healthcare · secure delivery

HIPAA audited file proxy

Authenticated HIPAA-compliant file delivery proxy for clinical documents. Tokenized URLs scoped to one document, one recipient, and one time window. Virus scanning before delivery, configurable retention per partner, full audit trail. Passed external HIPAA security audit on the first review.

.NET · token auth · audit log View case
CASE 22 / Healthcare · data systems

Clinical data warehouse

Long-running clinical data warehouse on MSSQL. Patient, encounter, and claim records normalized with full history, idempotent ETL batches against external partners, code-managed stored procedures, and read-only replicas for analytics teams. Survived years of feature work without losing referential integrity.

.NET · MSSQL · Windows services · ETL View case
CASE 23 / Healthcare · API hub

Clinical data aggregation hub

API hub aggregating multiple clinical data sources behind a single read-friendly contract for internal teams. Typed C# SDK shipped to consumers, schema-versioned endpoints, per-request budgeting, and audit logging so compliance knows who accessed what and when.

.NET · ASP.NET Core · typed SDK View case
CASE 24 / Education · accounting

Online accounting school

Online learning platform for accounting professionals. Multi-language course catalogs, recorded video lessons on a CDN, quiz and graded assignment engine, automatic certificate issuance on completion, and Stripe subscription billing tied to course progress.

Node · Express · video CDN · Stripe View case
CASE 25 / Gaming · legacy

Online casino platform

Early-career platform with a high engineering bar: game lobby, KYC at signup, responsible-gaming controls, multi-currency wallet with strict ledger integrity, RNG fairness logging, and a cryptographic audit trail a regulator can replay session by session.

classic web · KYC · payments · audit View case
CASE 26 / Geo · platform

Map-based geo-resume platform

Map-based platform for location-aware professional profiles. Candidates pin an availability radius, recruiters search by proximity or travel-time isochrone, and branded micro-sites per region drive local SEO. Built on the Google Maps API with custom clustering and geocoding cache.

Google Maps API · geocoding · clustering View case
CASE 27 / Dating · agency-led

Dating platform, agency-led

Two-sided agency-led dating platform with distinct workspaces for matchmakers and members. Agency-side profile curation and managed introductions, member-side KYC onboarding, moderated messaging, WebRTC video meet rooms, and a multilingual interface for international clientele.

web · video · payments · KYC View case
CASE 28 / Construction · multi-country

Construction company sites, multi-country

Multi-country website framework for construction firms. Per-region branding, project portfolios with rich media, localized content and units of measurement, and quote flows that route leads to the right regional office by visitor location. Shared codebase, distinct themes per market.

headless CMS · localization · regional CDN View case
CASE 29 / E-commerce · Shopify

Artisan salt store with recipe content

Shopify storefront for a small-batch culinary salt brand with author-led recipe content. Custom Liquid theme links recipes to ingredient products, structured Recipe schema earns rich snippets in search, and the founder publishes content and ships orders without an agency on retainer.

Shopify · Liquid · Recipe schema View case
CASE 30 / Emerging tech · brand site

Brand site for a pioneering AR and VR studio

Public brand site for one of the longest-running AR and VR studios in the United States. WebGL teasers load only when visible, interactive 3D set-pieces run on framerate budgets, and the full site loads on conference Wi-Fi without compromise.

WordPress · WebGL · video CDN View case
CASE 31 / Real-time · video

One-on-one video chat

Peer-to-peer WebRTC video calling for healthcare consultations, support workflows, and creator-fan platforms. STUN and TURN fallback for NAT traversal, encrypted media, consent-gated recording, virtual backgrounds, and reconnection logic that survives partial network drops.

WebRTC · STUN/TURN · TypeScript · Node View case
CASE 32 / Real-time · streaming

Live video streaming, one-to-many

One-to-many live broadcast platform with WebRTC for sub-second interactive latency and HLS for adaptive-bitrate reach at scale. Viewer-side captions, chat sidecar, recorded VOD, DRM-aware paywall hooks, and CDN egress that absorbs audience spikes without reconfiguration.

WebRTC · HLS · CDN · FFmpeg View case
CASE 33 / Real-time · messaging

Real-time text messaging

In-app real-time messaging for healthcare member portals, support inboxes, and community platforms. WebSocket transport with presence, typing indicators, read receipts, threading, reactions, and attachments. HIPAA-grade audit logs ship by default. End-to-end encryption is optional per channel.

WebSocket · Postgres · Redis pub/sub View case

More work across other niches we did not put on the homepage. Pharma, hospitality, fintech, retail, esoteric, education, automotive, B2B SaaS, internal tooling. 10 years. Hundreds of sites. Most under NDA.

Want to see the long form? Get in touch
Studio startups our own product bets
STARTUP 01 / Auto · vertical SaaS
Studio startup

Operating system for service stations

Vertical SaaS built for car service shops and garages. Bay scheduling tied to technician availability, parts inventory with live margin analytics, supplier integrations, customer portal with status updates, and retention loops. Built around the actual garage workflow, not adapted from generic CRM.

Auto vertical SaaS
Next.js · Postgres · Stripe Read thesis
STARTUP 02 / Vertical fintech
Studio startup

Funding marketplace, beauty vertical

Vertical financing marketplace for beauty professionals: solo creators, salon owners, indie brands. Working capital, equipment leasing, and growth loans matched to booking-based cashflow patterns that generic bank underwriting models miss entirely.

Beauty vertical fintech
.NET · Angular · MSSQL Read thesis
STARTUP 03 / Esoteric · community
Studio startup

Spiritism community platform

Paid membership platform for a spiritism community. Live sessions, recorded archives, member directory, Stripe subscription billing, ritual scheduling, and region-aware content gating. Built for moderation at scale in a sensitive vertical most agencies will not take on.

Spiritism community platform
Next.js · Stripe · Supabase View case

Real artifact

A typed conversion event we wire into every client site.

No abstractions, no diagram. The shape of code we wire into client sites so revenue and conversions actually get counted, attributed, and optimised.

Strict types, consent-aware, PII-stripped before transport, and audit-logged. Same shape used across healthcare, e-commerce, B2B SaaS, and AI-agent products. Drop it in, hook it to your warehouse, watch the numbers.

How we engage

From first call to a system you can audit.

STEP 01

Scoped review

Two-week paid discovery. We map the system, the constraints, and the failure modes. You get a written technical plan.

STEP 02

Build with feedback

Weekly demos, working software each cycle. We ship to a staging environment that mirrors your prod, not a sandbox.

STEP 03

Production cutover

Telemetry, runbooks, and on-call coverage during the switch. We do not call something done until it has survived a week of real load.

STEP 04

Ongoing ownership

Retainer or handover, your call. If we hand off, your team gets the runbook, the dashboards, and a recorded walkthrough.

Brief us

Tell us what you are trying to ship.

Healthcare integration, an LLM agent that has to actually work, an internal platform someone forgot to maintain, or anything in between. We reply within one business day.

A short brief gets a real reply within one business day.

Budget range (optional)

By sending this you agree we can use your email to reply. Privacy policy.

Or email hello@quadevs.com.

Stack · manifest

Technologies we ship to production

stack.manifest read-only · 32 + many
Next.js primary
React primary
TypeScript primary
Node.js primary
Python primary
.NET primary
PHP site
PostgreSQL database
Microsoft SQL Server enterprise
Redis caching
Elasticsearch search
Stripe payments
Shopify commerce
WordPress cms
Twilio comms
Amazon Web Services cloud
New Relic observability
Swift mobile
Kotlin mobile
GitHub ops
Express backend
Vite tooling
Mapbox geo
Cloudflare cdn
Docker devops
Nginx web server
Sentry errors
WebRTC real-time
Three.js webgl
Tailwind CSS styles
Supabase baas
GraphQL api
and many more on request
~ tail stack.manifest

Plus FHIR R4, SMART-on-FHIR, HL7, OAuth2, WebSocket, GPU workers, OpenCV, LeadTools, and whatever else your stack runs on. Tell us what you run.