Now at Workday · Developer PortalFrontend & Developer Platform

Good defaults, fewer decisions, faster teams…

I'm Daria Calwell — a platform engineer working where frontend architecture meets build, deploy and developer tooling. I design the shared architecture, modular deploys and CI that let many teams move independently, and fast.

The paved road
  1. Pull requestopened by any team
  2. BuildTurborepo · only what changed
  3. TestVitest + Cypress · 4 shards
  4. Previewephemeral env · pr-214
  5. ShipS3 + CloudFront · independent deploy
Good defaults, built in.team decides: what · platform decides: how

Problems worth a platform.

Each started as something slowing many teams down at once. Pick one to read how it went.

Performance · 01 / 05

UI load time: 14s → 2.5s

Scope · User-facing
The problem
The UI took 14 seconds to load.
What I did
  • Benchmarked real UI metrics with Chrome DevTools and Lighthouse to see what users actually felt.
  • Fixed what the numbers pointed to, one bottleneck at a time.
Outcome
Load time down to 2.5 seconds.
CI/CD · 02 / 05

An environment for every pull request

Scope · Multi-team pipeline
The problem
Build, test and deploy were coupled, so feedback on a change was slow for a multi-team platform.
What I did
  • Implemented ephemeral PR environments with automated build, deploy and teardown.
  • Built multi-stage pipelines with S3-based artifacts to decouple build, test and deploy.
  • Parallelized Cypress with sharding, added conditional jobs and dependency caching; led the Jest → Vitest migration.
Outcome
Shorter CI runs and faster feedback on every pull request.
Frontend architecture · 03 / 05

From one deploy to many

Scope · Org-wide platform
The problem
One monolithic frontend deployment meant teams blocked each other on every release.
What I did
  • Split it into modular, independently deployed applications on S3 + CloudFront, Turborepo and CI/CD.
  • Introduced Terraform and GitHub Actions for infrastructure as code.
Outcome
Teams release on their own schedule, with better scalability and release velocity.
Platform foundations · 04 / 05

A starter architecture teams actually adopt

Scope · Adopted across teams
The problem
Teams needed a consistent, production-ready starting point for new applications.
What I did
  • Built a reusable starter architecture with the good defaults baked in.
  • Designed a micro-frontend architecture with CI/CD pipelines and observability (Datadog, Rollbar) included.
Outcome
Adopted across teams as the default foundation for new work.
Systems integration · 05 / 05

Astra DB × watsonx.data

Scope · Cross-product, cross-org
The problem
Two separately built products had their own identity, org and provisioning flows.
What I did
  • Spearheaded the UI integration of Astra DB with watsonx.data.
  • Worked with backend teams on API design, auth flows and system contracts.
Outcome
Identity, org mapping and provisioning aligned across both products.

Where I add leverage.

The areas I get pulled into most, and the tools I reach for.

Frontend architecture

Application structure, state and GraphQL integration patterns for multi-tenant control-plane UIs.

  • React
  • TypeScript
  • GraphQL
  • Node.js
  • Design systems
  • Micro-frontends
Build & deploy platform

Modular, independently deployable apps with CI/CD, caching and infrastructure as code.

  • Turborepo
  • Webpack
  • GitHub Actions
  • AWS CDK
  • Terraform
  • S3 + CloudFront
Developer tooling & AI

Internal tools that give engineers time back, including an AI assistant built with LangChain and GPT.

  • LangChain
  • OpenAI
  • Unstructured
  • Vitest
  • Cypress
Infra-aware frontend

Caching, performance, auth and observability treated as part of the UI, not an afterthought.

  • Datadog
  • Splunk
  • Rollbar
  • OIDC / JWT / SSO
  • AWS
Technical leadership

Setting technical direction, partnering with product and backend on API contracts, and growing engineers into system thinkers.

  • Technical strategy
  • API design
  • Cross-functional alignment
  • Mentorship
  • Talks

Where I've been.

2019 — now
2026 — NowSenior EngineerDeveloper Portal · Workday
2024 — 2026Tech Lead / Staff UI LeadAstra DB Control Plane (Frontend Platform) · IBM / DataStaxLed the control-plane UI for a serverless database and moved it from one monolithic deploy to independently shipped apps.React · TypeScript · GraphQL · Turborepo · AWS
  • Led engineering for the Astra DB control plane UI, a multi-tenant frontend platform for provisioning and managing a serverless database
  • Drove the move from a monolithic deployment to modular, independently deployed apps (S3 + CloudFront, Turborepo, CI/CD)
  • Owned frontend system design and technical direction: application structure, state management and GraphQL integration patterns
  • Spearheaded UI integration with watsonx.data, aligning identity, org mapping and provisioning across systems
  • Established best practices for infra-aware frontend development: caching, performance and observability
  • Mentored engineers and partnered with product and backend teams on API design, auth flows and system contracts
2021 — 2024Senior Software EngineerFrontend Platform Engineering · Guild EducationBuilt frontend platform foundations, including a starter architecture adopted across teams.React · TypeScript · GraphQL · AWS CDK · GitHub Actions · Turborepo
  • Built and scaled frontend platform foundations, including a reusable starter architecture adopted across teams
  • Designed a modular deployment system (S3 + CloudFront + CI/CD) improving release velocity and reliability
  • Led the migration from a monolith to independently deployable services and micro-frontends
  • Developed internal tools, including an AI-powered chatbot using LangChain + GPT for developer productivity
2021Tech LeadAstra DB UI Platform · DataStaxLed the Astra DB UI: network security, private connectivity and multi-region features.React · GraphQL · Kubernetes · Datadog · TypeScript
  • Led development of the Astra DB UI for managing cloud-native databases
  • Delivered network access controls, private connectivity setup and multi-region configuration
  • Facilitated architecture discussions and guided scalable frontend patterns
2019 — 2021Tech LeadFrontend Architecture · Kin + CartaLed frontend architecture for enterprise applications and mentored engineers.React · Redux · REST · Cypress · Jest · Docker · Apollo
  • Led frontend architecture for enterprise applications, focused on scalability, performance and maintainability
  • Introduced functional programming patterns and improved overall code quality
  • Mentored engineers and guided technical decisions across projects

Talks & community

  • State MachinesReact Denver
  • React Architecture overviewMagellan dev team
  • Why JavaScript?Galvanize reunion

Education

  • Web Development ImmersiveGalvanize
  • BA, English · French · Education