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Darius Cepulis

Darius Cepulis

Senior Community Engineer

Pretends he knows more about coffee than he does. Happier when he's outside. Thinks the web is pretty neat.

Written by Darius:
A skeleton hand grips a pink quill. Aware of its finite time, it scribes code onto a black surface.

Published on October 14, 2024 (8 days ago)

Dave Kiss
Darius Cepulis
Rob Mach
By Dave, Darius, and Rob11 min readProduct

When's the last time you audited your developer docs? We felt the pain that our customers were facing with our docs — and set off on an adventure to fix it.

A deeply confused, yet well-intentioned robot, throwing up his arms in confusion

Published on September 6, 2024 (about 2 months ago)

Darius Cepulis
By Darius Cepulis7 min readEngineeringAI

We can learn a lot about the current state of large language models by talking about why we chose not to use an AI chatbot on our documentation site.

A player showing a video of two people talking. The people are labeled with their names, Matt and Nick. Below the player, a graphical representation of a transcript.

Published on August 15, 2024 (2 months ago)

Darius Cepulis
By Darius Cepulis11 min readEngineeringAI

Build an interactive transcript with Mux Player CuePoints and AI. Use AI for caption generation, Speaker diarization (identification), and text formatting.

Two boxes, one labeled server and the other labeled client, are closely connected by two lines.

Published on May 16, 2024 (5 months ago)

Darius Cepulis
By Darius Cepulis13 min readEngineering

What can you do with Server Components and Actions in React 19? Let’s talk about how React 19’s features are a big deal, even for a simple marketing site.

A Swiss Army knife with various video player symbols (and a banana?) floating near each tool

Published on April 15, 2024 (6 months ago)

Christian Pillsbury
Darius Cepulis
By Christian and Darius17 min readVideo education

A video playback engine enables more complex video use cases like adaptive bitrate streaming and DRM, but at the cost of bundle size. Is it worth it?

A diagram depicting a client device interacting with a server via a communication line. A lightning bolt sits in between both the client and server.

Published on August 10, 2023 (about 1 year ago)

Darius Cepulis
By Darius Cepulis9 min readEngineering

React Server Actions offer a way of simplifying posting data to the server by calling a simple function instead. But do they live up to the promise?

An illustration of a browser window showing different page components highlighted in different colors, depicting that some components are client-rendered while others are server-rendered.

Published on July 19, 2023 (over 1 year ago)

Darius Cepulis
By Darius Cepulis20 min readEngineering

Server Components run on the server instead of the client, giving you control over your bundle size and data fetching. Here’s everything we learned about them.

A documentation icon and the letters M, U, and X in an isometric grid

Published on January 20, 2023 (almost 2 years ago)

Darius Cepulis
By Darius Cepulis15 min readEngineering

Great documentation is the backbone of a great API company. How do you scale it and keep a good experience? Learn about information architecture, Next.js 13, React Server Components, and Tailwind.

A browser showing Mux Player loading

Published on November 1, 2022 (almost 2 years ago)

Darius Cepulis
By Darius Cepulis6 min readEngineering

With lazy-loading and a blurhash placeholder, we make the loading experience of Mux Player feel great in our Next.js app

A mockup of custom Mux water bottles that were designed for CascadiaJS conference.

Published on September 13, 2022 (about 2 years ago)

Dave Kiss
Dylan Jhaveri
Darius Cepulis
Amin Amos
By Dave and 3 others6 min readEvents

Mux was proud to be a sponsor at CascadiaJS 2022 – here's a recap of our experience in the high desert.

A screenshot of the Mux guestbook project

Published on April 27, 2022 (over 2 years ago)

Dave Kiss
Darius Cepulis
By Dave and Darius10 min readEvents

If you’ve ever attended a conference in person, you know just how taxing they can be. You try to present your best self: unravel the hotel iron from the closet, work that one uncooperative cowlick to ...