Neciu Dan is a seasoned software engineer with over 14 years of expertise in the tech industry, host of the Señors @ Scale podcast, and creator of the sold-out Lizard to Wizard engineering workshop. He has a proven track record, having served as the technical co-founder and tech lead of CareerOS, a Senior Product Engineer at the New York e-commerce brand AdoreMe, and a Senior Software Engineer at the food delivery company Glovo.
Beyond his technical contributions, Dan is an esteemed international speaker and mentor. He passionately encourages best development practices, with a keen focus on testing, accessibility, and security. His recent speaking engagements include esteemed conferences like React Alicante, React Summit, React Rally, Utah JS, Techorama, and Frontmania.
Discover actionable insights from conversations with senior engineers about scaling applications, teams, and careers.
Señors @ Scale host Neciu Dan sits down with Santosh Yadav, principal developer advocate at CodeRabbit and one of only around 80 GitHub Stars in the world. Santosh started hating C in 2004, fell for C# by 2008, and turned a year of open source contributions to Angular and NgRx into a stack of community titles — Google Developer Expert, GitHub Star, Nx champion, and Microsoft MVP. As a staff engineer at Celonis he led the move of 20-plus apps to module federation and drove Nx adoption across 30-plus teams when the product grew from four apps to thirty. From the year-long incremental migration off a single deployable unit, to why polyrepos can't give AI tools the context they need, to how Nx's affected graph and build caching tame a 20-million-line monorepo, to running code review for free for open source at CodeRabbit, this is the monorepo conversation grounded in someone who actually shipped one at scale.
Señors @ Scale host Dan Neciu sits down with Nicolas Beaussart-Hatchuel, staff engineer at Payfit and one of the maintainers of TanStack Router. Nicolas's path started with C macros to auto-generate his student paper headers and frontend learned by building phishing login pages for practice, took him through an iframe-based AngularJS-to-Angular 2 micro frontend migration at a web radio platform, into open source contributions across NX, ESLint, Vite and Hasura, and finally to maintaining one of the most ambitious routers in the React ecosystem. From why TanStack Router exists, to migrating Payfit's 300-route, 1.5-million-line codebase off React Router v5 using the strangler pattern, to collapsing 25 polyrepos and five different micro frontend strategies into a single modular monolith, this is the routing conversation most engineers never get.
Señors @ Scale host Neciu Dan sits down with Mark Erikson, maintainer of Redux and senior front-end engineer at Replay.io, where he works on a time-traveling debugger. Mark's path started with a 286 he got at eight years old, ran through a computer science degree, four years teaching English in China, embedded software at Northrop Grumman emulating legacy CPUs in old aircraft, and a chain of projects — GWT, jQuery, Backbone — that led him to React and Redux. From the @deprecated backlash that had people insulting him on the internet, to why the Redux core hasn't meaningfully changed since 2016, to what RTK Query actually solves, the underused listener middleware, building source maps into React's own build pipeline, and how Replay's recordings now hand debugging over to AI agents — this is the Redux conversation grounded in two decades of shipping software.
Señors @ Scale host Dan Neciu sits down with Dominik Dorfmeister — better known as TkDodo — the maintainer of TanStack Query and a software engineer at Sentry. Dominik's path started at a technical high school in Vienna, ran through JVM backend work in Java and Scala, and turned to frontend around the introduction of TypeScript. During the pandemic lockdowns in Austria he started answering questions in the TanStack Discord, got addicted to the instant gratification of helping people, and slowly turned that into a blog, a first code contribution six to eight months later, and eventually maintainership of TanStack Query. From tracked queries and the chaotic version-three-to-four rename, to the version-five mistake he still dreads, to ripping 28,000 lines of dead code out of Sentry with Knip and building Sentry's new design system, this is the open source maintenance conversation most developers never get to hear.
Señors @ Scale host Neciu Dan sits down with Dan Odell, staff software engineer at Canva working on systems that serve over 250 million active users. Dan's path started with electronic engineering in the late 90s, took him through marketing sites for IBM and Johnson & Johnson at AKQA, his own consultancy for clients like UNICEF and MINI, nine years on Volvo's e-commerce and car configurator, and finally to Canva's charts and visualizations team. He's also the author of Performance Engineering in Practice, out now through Manning's Early Access Program, which introduces the Fast by Default framework. From feature-flagged staged rollouts and test parties to operational transforms, the performance decay cycle, shrinking the critical path, and perceived performance, this is the conversation about making software fast — and keeping it fast — at scale.
Señors @ Scale host Neciu Dan sits down with Kadi Kraman, software developer at Expo working on the tools that make React Native development as smooth as possible. Kadi's path started with C++ in a university maths degree, took her through Angular 1, scientific programming for pharmaceutical and defense companies, five and a half years at Formidable, and finally to Expo itself. From the limitations of early React Native to development builds, EAS workflows, fingerprint-based repacks, and the right way to think about over-the-air updates, this is the React Native conversation most web developers never get.
Señors @ Scale host Neciu Dan sits down with Nico Martin — open source ML engineer at Hugging Face working on Transformers.js, and Google Developer Expert in AI and web technology — to go deep on running machine learning models directly in the browser. Nico breaks down architectures vs. weights, quantization, tokenizers, ONNX, WebGPU, and why on-device AI is the right answer for a huge class of problems. He also shares the road from ski instructor and self-taught web developer to landing what he calls his dream job at Hugging Face.
Señors @ Scale host Neciu Dan sits down with Giorgio Polvara, Staff Engineer at Perk (formerly TravelPerk), who joined when the company was 15 people in two flats with a hole knocked through the wall and helped build the frontend foundations that still hold up at unicorn scale. Giorgio covers the multi-year migration from a monolithic frontend to vertical micro-frontends, why their first attempt with single-spa didn't work, how they pulled off a full rebrand behind feature flags without leaking, and the staff engineer mindset of treating every feature as a system improvement.
My site ran Astro 3 for three years. When Anthropic released the new Fable model, I tested it on the scariest item on my backlog: a three-major-version upgrade. This is how it went, numbers included.
I feel like Service Workers are a underused technology with a lot of benefits, but very complex to set up and often misunderstood and what they do. Here are some case studies from Slack, Mux and me on where and how to use Service Workers
Sourcemaps unlock some observability benefits but might expose your codebase. Check out how they work, and how to protect yourself.
One room of React developers had all used TanStack Query. The next room had barely heard of it. This is the version of the talk that assumes nothing.
Angular. tj-actions. Cline. TanStack. The same class of attack has been quietly hijacking publish pipelines for two years. Here's what it is, how it works, and what you need to do today.
Small, focused libraries I found useful. Each has a clear job and a payoff you'll feel in the first use.
Check out my latest educational videos on React, JavaScript, and frontend development best practices.
View all videosLearn the keys to success in web development, from accessibility to performance, and how to craft a secure software
