# Tania Papazafeiropoulou > Senior Front-End & Mobile Engineer & Tech Lead. Developer for 13 years, most of them on React and React Native apps used by millions of people. I own systems end to end, work closely with product, design and backend, and care about performance and accessibility. This is her personal site: what she has built, how she works, and what she writes about. Everything here is written by her. The CV is the authoritative record of where she has worked and when. ## Pages - [Home](https://tany4.com/): who she is, in short. - [Work](https://tany4.com/work): the projects, what she built on each and what changed as a result. - [CV](https://tany4.com/cv): roles, dates, employers and skills. Also available as a [PDF](https://tany4.com/TaniaPapazafeiropoulou-CV.pdf). - [Blog](https://tany4.com/blog): 15 posts, newest first. - [About](https://tany4.com/about): the non-work part. ## Experience - **Senior Mobile Engineer (Contract)**, The Ready Collective — 05/2026 to Present - **Front-End Tech Lead**, Olio — 08/2023 to 03/2026 - **Senior Front-End Developer**, Olio — 09/2018 to 08/2023 The [CV](https://tany4.com/cv) has the full history, the earlier roles and the skills. ## Writing - [What I'm taking from Kent C. Dodds's agent setup, and what I'm not](https://tany4.com/blog/posts/what-i-take-from-kent-c-dodds-agent-setup): Kent C. Dodds ships code he hasn't read. I run AI coding agents in parallel the same way. What our setups share, what I'm taking from his, and what I'm not. - [Running AI coding sessions in parallel](https://tany4.com/blog/posts/running-ai-coding-sessions-in-parallel): How I went from two or three AI coding sessions to as many as fifteen at once on a two-person team, what broke along the way, and the hub session I added to keep track of it all. - [Greek voice commands for Android Auto](https://tany4.com/blog/posts/greek-voice-commands-for-android-auto): Google Assistant doesn't speak Greek in the car, so I built an Android Auto app in Kotlin that does: Greek speech, and contacts saved in Greeklish. - [Teaching my job-hunting MCP server what it can do](https://tany4.com/blog/posts/teaching-my-job-hunting-mcp-server-what-it-can-do): My MCP server's agent kept saying things weren't possible, adding duplicate rows and ignoring a linked doc. The fix was better tool descriptions. - [Taking my job-hunting MCP server remote](https://tany4.com/blog/posts/taking-my-job-hunting-mcp-server-remote): I turned my job-hunting MCP server from a laptop-only tool into a remote one I use from my phone: the transport switch, free hosting, and a 502 only ChatGPT hit. - [Fixing the app I built for my dog's medication schedule](https://tany4.com/blog/posts/marios-helper-v2): A year ago I built an Expo app to remind me about my dog's eye drops. I came back to it with Claude Code, fixed the notification bugs, and rewrote most of it. - [Building a job-hunting MCP server](https://tany4.com/blog/posts/building-a-job-hunting-mcp-server): I built a personal MCP server that researches companies, scores how well a job fits, and tracks my applications. - [7 Years at Olio](https://tany4.com/blog/posts/seven-years-at-olio): What I learned in 7 years at Olio, going from mid-level developer to Tech Lead: architecture, shipping products and working with people. - [Vibe coding an AI chatbot into my website](https://tany4.com/blog/posts/vibe-coded-ai-chatbot-weekend): One evening I built a small AI chatbot into this site with the Vercel AI SDK. It only answers questions about my actual work. - [Getting Confident with GitHub MCP Server: A Real QA Win](https://tany4.com/blog/posts/getting-confident-with-github-mcp-server-a-real-qa-win): I had to QA a back-end PR with almost no context. GitHub MCP Server helped me do it, and also got one important detail wrong. - [Experimenting with GitHub MCP Server as a Front-End Dev](https://tany4.com/blog/posts/experimenting-with-github-mcp-server-as-a-frontend-dev): Using GitHub's MCP Server as a front-end developer to understand back-end code faster and improve my types, without jumping between repos. - [Build automation using Fastlane and Travis](https://tany4.com/blog/posts/build-automation-with-fastlane-and-travis): A year ago releasing the Olio React Native app took most of a day and sometimes failed anyway. Schemes, build variants, match and fastlane got it down to an hour or two across three stores. - [JS VidCon 2020](https://tany4.com/blog/posts/jsvidcon-2020): My JS VidCon talk on how Olio uses React Native to reduce food waste: how we migrated a production app quickly and kept performance and developer experience under control. - [Mocking React Native 0.61 modules with Jest](https://tany4.com/blog/posts/mocking-react-native-0.61-modules-with-jest): React Native 0.61 removed Haste and broke a lot of Jest mocks. Why it happened and how I fixed it. - [React Conf 2019](https://tany4.com/blog/posts/react-conf-2019): My talk at React Conf 2019 on how we built and migrated the Olio app to React Native with a tiny team, what broke, and what we'd do differently. ## Contact hello@tany4.com. She is open to being contacted about work.