Building ElixirNoDeps: A Terminal Presentation Tool with Zero Dependencies

When Jeremy Searls and I started preparing for our ElixirConf 2025 talk “Elixir is all you need: Rethinking dependencies,” From the start, we wanted to have a repo to help demonstrate the capabilities of the Elixir standard library. We faced an interesting challenge: how do you give a presentation about not using dependencies without using a presentation tool that’s built with dozens of them?

The answer was simple: build our own. With zero external dependencies.

What better way than to give the presentation from the repo itself?

The Initial Commit: “ElixirConf Here We Come”

It all started with a single commit on July 29th: 5e8818e initial commit- ElixirConf here we come. The goal was ambitious yet simple - create a terminal-based presentation tool using only Elixir’s standard library and built-in capabilities.

The Core Philosophy: Zero External Mix Dependencies

The entire project is built on one fundamental principle: no external Mix dependencies. This wasn’t just a constraint - it was the whole point. The mix.exs file literally has an empty deps function:

defp deps do
  # Zero external dependencies - that's the whole point!
  []
end

This forced us to rediscover what Elixir can do out of the box. Spoiler alert: it’s a lot.

Building the Foundation

The first few commits laid the groundwork:

Markdown parser: Built from scratch using Elixir’s pattern matching
Terminal rendering: Raw ANSI escape sequences and IO manipulation
YAML frontmatter: Custom parser for slide metadata
Keyboard navigation: Raw terminal input processing

Each component was an exercise in creative problem-solving. How do you parse YAML without a YAML library? Pattern matching and string manipulation. How do you handle raw keyboard input? Direct terminal control with Elixir’s IO system.

The Evolution: From Simple to Sophisticated

What started as a basic slide viewer evolved into something much more powerful:

Phase 1: Basic Presentation (July-August 2024)

Markdown slide parsing
Terminal rendering with ANSI formatting
Basic keyboard navigation
ASCII art generation for images

Phase 2: Remote Control Revolution (August 2024)

The game-changer came with the realization that conferences often have unreliable WiFi, but you always have your phone. Why not create a local network solution?

HTTP server: Built using Elixir’s built-in :inets
Mobile-optimized interface: Clean presenter controls
Speaker notes: Private notes visible only on the presenter’s device

Phase 3: Conference-Ready Features (August-September 2024)

Interactive polling: Live audience participation
QR code generation: For easy connection to the audience app
Timer warnings: Real-time slide timing feedback
Multi-role support: Presenter, audience, and viewer modes

Technical Highlights

No Dependencies, Big Features

The most impressive part? All of this was built without external dependencies:

HTTP server: Using Erlang’s :inets and :httpd
Image processing: ASCII art generation with pure Elixir
Image processing: For terminal image integration, we did have to stretch the definition of no dependencies and rely on imagemagick to support resizing erminal images for the presentation.
Terminal control: Raw ANSI sequences and IO manipulation

Architecture Decisions

Single Binary Distribution: The entire presentation tool compiles to a single escript binary. No installation, no dependency management - just download and run.

Local-First: Everything can run on your local network. No cloud services, no external APIs. Your presentation works whether you have internet or not. It also works from a deployed state.

Progressive Enhancement: Basic functionality works in any terminal. Advanced features (like sixel image rendering) are detected and enabled automatically.

The Real-World Test: ElixirConf 2025

The ultimate validation came when we used ElixirNoDeps to deliver our ElixirConf presentation. Not only did it work flawlessly, but the meta-aspect of using a zero-dependency tool to talk about zero-dependency development resonated strongly with the audience.

Key moments from the conference:

Live polling: The audience participated in real-time polls about dependency usage
Mobile control: Seamlessly navigated slides from my phone while the audience saw clean terminal output

Lessons Learned

1. Elixir’s Standard Library is Incredibly Powerful

You can build sophisticated applications without reaching for external libraries. Pattern matching, GenServers, ETS, the built-in HTTP stack - they’re all there waiting to be used.

2. Constraints Drive Creativity

Having zero dependencies forced creative solutions that ended up being more elegant than traditional approaches.

3. Local-First is Liberating

Not depending on external services or internet connectivity gives you incredible reliability, especially in conference environments.

4. Terminal Applications Still Matter

In an age of web apps and GUIs, there’s something powerful about a well-crafted terminal application. It’s universal, lightweight, and distraction-free.

The Numbers

After months of development, ElixirNoDeps supports:

250+ concurrent audience connections
Real-time polling and interaction
Multiple presentation formats (Markdown, with extensible parsing)
Cross-platform compatibility (macOS, Linux, Windows)
Zero installation presentation delivery
Complete offline functionality

All in a single binary with zero external Mix dependencies.

Open Source Impact

The project is now open source at github.com/ckochx/ElixirNoDeps, serving as both a useful tool and a proof of concept for what’s possible with Elixir’s built-in capabilities.

The response from the Elixir community has been fantastic.

Looking Forward

ElixirNoDeps proves that sometimes the best solution isn’t adding more dependencies - it’s rediscovering what you already have. As the Elixir ecosystem continues to grow, tools like this serve as a reminder that the language itself is incredibly capable.

The next time you’re about to mix deps.get another library, ask yourself: do I really need this? You might be surprised by what you can build with just Elixir.

Want to try ElixirNoDeps? Check out the GitHub repository or watch the ElixirConf 2025 presentation to see it in action.