Felix Andersson, Senior Fullstack Engineer

Senior Fullstack Engineer, building products people can trust.

Nearly six years shipping software other teams depend on: Cisco’s Magnetic design system and the Meraki Dashboard’s most used pages, and now the whole stack of Clayful, a student mental-health platform: Rails and Node services, auth, integrations and a mobile app. I also design and build products of my own, end to end.

See the work Email me

Fullstack ownershipRails and Node services, auth, integrations, a mobile app.
Production debuggingIncidents traced through logs and data to a measured fix.
Complex UIDesign systems, data-heavy dashboards, large tables.
AI-native toolingReview pipelines and agent skills teams run every day.

Felix Andersson, smiling, in a striped linen shirt against a dark studio backdrop. — Montevideo, UruguayNearly 6 years shipping software

Felix Andersson, smiling, in a striped linen shirt against a white studio backdrop. — Montevideo, UruguayNearly 6 years shipping software

KatArch

A narrated video course on software architecture, built from what the twelve winning teams of the Architecture Katas left in writing.

Scenes timed to the voice
Captions drawn by the player
One player, two languages

Case study Website Source

Experience

Nearly six years shipping production software. Most of them at Cisco as the frontend maintainer Meraki teams count on; now the whole stack at Clayful, from Rails and Node services to the mobile app, and the tools each team needed before anyone asked.

Résumé, PDF

Dec 2020 to Jul 20218 mos

Frontend Engineer

Device Magic · through Vairix

My first product. I ended up owning the whole web frontend after the senior developer left, and took it to its MVP launch.

A dynamic forms engine: unlimited nested sections, recursive state and real-time expression evaluation.
When the backend switched to an incompatible XML format, a client-side adapter that translated it on the fly instead of a rewrite.
Large forms made orders of magnitude faster by reworking the algorithms and the rendering.
The UI for a webcam barcode scanner: a focused scan area with real-time feedback.

React
State management
Performance
Ownership

Aug 2021 to Jul 20221 yr

Frontend Engineer, Design System

Cisco, Magnetic design system · through Vairix

Joined Magnetic, Cisco’s design system, while it had its first components, and helped take it to its first production release.

Reusable React components with accessibility and performance as the bar, not an afterthought.
Detailed design specs turned into components, working directly with the design team.
Testing and QA for the library’s first production release.

React
TypeScript
Accessibility
Design systems

Aug 2022 to Oct 20231 yr 3 mos

Frontend Engineer, Product Implementation

Cisco Meraki, Meraki Dashboard · through Vairix

Built the most used data pages of the Meraki Dashboard: Access Points, Switches and Clients.

Tables with filtering, sorting and export, optimized for the largest customers’ datasets.
Planned and broke down critical features so several developers could build in parallel.
Moved teams from legacy UI components to Magnetic while keeping what they had working.

React
TypeScript
Data-heavy UI
Planning

Nov 2023 to Sep 20262 yrs 11 mos

Frontend Product Engineer

Cisco, Magnetic component library · through Vairix

The proactive maintainer of the React and TypeScript library that Meraki teams build on. When leadership needs something, I take it from spec to release.

Complex data table features built to detailed design specs, the most demanding components in the library.
Support for the hundreds of developers who adopt the library, and the review standards that keep it stable.
OKR epics leadership needed, owned from problem to release.
Tools and ideas for the team beyond the tickets, like the AI stack below.

React
TypeScript
Design systems
Accessibility
AI tooling

A few examples

The team’s AI engineering stack. When leadership made AI adoption an OKR for every team, I used it to raise our quality bar instead of letting it slip. In two to three months: an AGENTS.md, coding skills with explicit boundaries, and a pre-push hook that runs a breaking-change scanner (designed from every hotfix and revert in the repo’s history) and a review orchestrator with five specialized reviewers, calibrated on 100+ comments distilled from thousands. The team still runs it on every push.

Responsive tables on large datasets. A table filter that froze typing on big customers’ data, split into short slices that yield to the browser, so matches render as they arrive.

What the team lead said. That it was exactly what the team needed, and key to opening the repo to outside contributions.

Oct 2026 to now1 mo

Fullstack Engineer

Clayful, student mental-health platform · through GoGrow

The whole stack of a platform schools use for student mental health: a Rails API, Firebase Cloud Functions, a Next.js and Capacitor mobile app, and the Webflow site, wired to Salesforce, Zendesk, Memberstack and Customer.io.

Production incidents traced through Sentry, Cloud Run logs and the data, to a fix measured in production.
Rails background jobs (Solid Queue) that respect third-party rate limits: concurrency caps, jittered backoff, change detection.
Auth and identity across four codebases: JWKS caching, server-side JWT signing, key rotation, recorded in ADRs.
Salesforce data fixed at the source, then backfilled with a backup, dry-run and revert protocol.
Observability for minors’ health data: Sentry with PII scrubbing, a Cloud Logging fallback, a Node 20 to 22 upgrade, Android releases unblocked.

Ruby on Rails
Node.js
Firebase / GCP
Salesforce
Auth
Capacitor
Sentry

A few examples

A class logged out at once. Students lost their login in the first minutes of class. Lining up Sentry with the backend’s request logs minute by minute showed the network working fine, and the auth vendor’s per-IP limit tripping on a whole school behind one address. A shared request layer made the start-of-class burst about four times smaller, with outages reported once and retries spread out.

401s on valid logins. The serverless API rejected good tokens whenever the vendor’s key file failed to download, which it did on every request. Keys cached per instance with a bundled fallback, proven on a local bench with a fake S3 that fails on demand.

Jobs that stopped flooding Sentry. Bulk roster imports fanned out into bursts of sync jobs that hit Zendesk’s and Memberstack’s limits, until Sentry was dropping 97% of the API’s errors. Throttled queues with backoff that honors Retry-After made the real errors visible again.

How I got here

At 8 or 9 I found Scratch, MIT’s visual programming language for kids, and fell in love with it. Before high school I ran a website of flash games packaged to play offline, so kids could download them onto their school laptops and keep playing at home without internet. Later I made the national top ten of ANIMATE, Uruguay’s animation contest, two years in a row.

I still care most about the same thing: software people can trust. Complex UIs, and the production problems behind them, are what I enjoy most. Agents are part of how I build now; I own the product thinking, design direction, architecture and review.

8–9years old
when I found Scratch, MIT’s programming language for kids
300k+page views
on my site of offline flash games, from other kids
2×top ten
in ANIMATE, Uruguay’s national animation contest

Toolset

Every day: TypeScript, React, Node, Ruby on Rails, SQL, CSS, accessibility, performance
Backend and data: PostgreSQL, Solid Queue, Firebase Cloud Functions, Firestore, webhooks, JWT and JWKS, rate limiting, Python and FastAPI, WebSockets
Integrations and infra: Salesforce (SOQL, Flows), Zendesk, Memberstack, Customer.io, GCP and Cloud Run, Kamal, GitHub Actions, Sentry
Frontend and mobile: Astro, Svelte 5, Next.js, Capacitor and Ionic, Radix UI, Tailwind, Motion, design systems
Testing: RSpec, Jest, Testing Library, Playwright, Cypress, axe-core
AI in the loop: Claude Code, Codex, Cursor, agent skills and review pipelines, streaming LLM output