Matthew Duff Learning, writing, and building in the open

Hiring a part time Elixir or Ruby developer: Going on a journey together to build something people love using

Hiring a part time Elixir or Ruby developer: Going on a journey together to build something people love

UPDATE: NO LONGER ACCEPTING APPLICANTS: I have moved forward with four different candidates at this point into the final stage. I am no longer accepting applicants. Thanks for everyone who expressed interest. I am trying to let everyone know who submitted an application about the decision, if it’s to move forward to the next phase or if I went a different direction. Thanks for the time and effort you put into applying.


About me: I’ve worked in tech companies for about 11 years now. At, GitHub, and most recently LaunchDarkly. I’ve decided I want to make some #smallbets and start my own company. I believe we can make a product that brings people joy and helps them achieve their goals.

The opportunity: A contracting role for up to $100/hour, up to 20 hours per week, located anywhere in the world.

What will we be building?

I want to build a competitor to MyFitnessPal and similar applications. The app will be called This is primarily to scratch my own itch, but I am optimistic we can build something compelling enough that it provides other people value and creates a small business. The vast majority of our time is going to be focused on building. We will try to keep meetings to an absolute minimum. We are going to cap the amount of time we spend on building to 20 hours per week. Work usually expands to fit the size allotted to it. By limiting the amount of time we can spend each week it’ll force us to focus, say “no” to some worthy goals, and ensure we are only doing the essential. I am in need of a strong Elixir or Ruby developer to work with me on this project. This project should be viewed as a creative journey.

Preferred qualifications

  • Strong Elixir or Ruby experience
  • Famliarity with CI/CD and an ability to use GitHub proficiently
  • An ability to deploy and maintain the site
  • Enough knowledge about Tailwind CSS where you can wire things up to make them look decent, until we hire a designer (would hire after we’ve proven the general value and data model/functionality)

If you meet some of the qualifications above, but not all of them, but believe you can add signficant value, please reach out.


  • $100/hour

How we will work together

Constraints: I believe constraints are generally very good. The more we narrow what we are trying to accomplish the faster we can move there. We will work together for at most 20 hours per week, paid hourly. This constraint will force us to focus on the most essential tasks at hand. We will need to ruthlessly prioritize. This first iteration of the application will be six weeks long of contract work. We will see what we can build in six weeks’ time.

Few meetings: We will meet together weekly where you will demo the work you have done for the week. We will walk through the choices that were made, hurdles encountered, and the decisions for what the next iteration of the application should focus on the following week. These will provide you a chance to highlight the great work you have done and provide us an opportunity to brainstorm on direction. Of course, these sessions will be paid. I will be available if any questions arise for us to sync, or answer any questions in Pull Requests, or GitHub issues, as they arise.

An emphasis on shipping early and often: My goal is to get this application in people’s hands as quickly as possible so we can focus on improving the product. Feedback from users will be some of our most valuable direction. Ideally I will be using the application within the first week or two, warts and all. We will try to create an efficient and thoughtful machine of feedback and iteration to create a tool that people love and consider an essential tool to live the life they love.

Respect for time: There will be clear expectations of how we work together. No late night texts. We will be driven by making our creative vision a reality, but we will move this objective forward in a calm, deliberate manner. People overestimate what they can do in the short term, but dramatically underestimate what they can do in the long term. I want to build something incredibly great in the long term and believe that can be done in a calm, thoughtful manner.

A focus on outcomes: We will use an hourly pay rate as it’s a simple way to work together before we have built high levels of trust. However, your performance will primarily be evaluated based on results and outcomes.

Interview process:

  • Phase one: Submit an email to (matt at peakstreak dot co) outlining
    • Your experience with Elixir/Phoenix or Ruby/Rails (keep in mind I value honesty and transparency) with examples illustrating, as best you can, what you are capable of
    • How you work best and the environment you do your best work in
  • Phase two: I will go through applications and find four candidates who have stood out and have made me feel like there is considerably reduced risk on my part by hiring them because of their demonstrated ability and the hope that we could work well together
  • Phase three: I will reach out to four of those applicants to quickly discuss moving forward (hopefully 10 - 15 minutes). I’ll grant each of those four applicants access to a repository to submit a pull request fixing one bug and adding some standard CRUD functionality into the existing application. This will be paid for work, paying $500 for the submission of the pull request (at a reasonable level of “done”) that satisfies the requirements of the functionality/bug fix. We will discuss the code changes synchronously in a 30 minute meeting and review the pull request.
  • Phase four: I will select one of the four candidates to move forward based on their submission and our contracting agreement will begin.

A note about diversity: I’d like to hire someone for this role who provides a different perspective than me. I believe diversity of thought and experience makes for creating better tools. Candidates from other countries (who people in the United States are legally allowed to work with) are welcomed to apply. The compensation will be the same regardless of where you reside in the world.

A note to recruiters: Please do not reach out to me about this opportunity. I want to work closely with one person, with as little overhead as possible. I do not want to work with your agency, regardless of how great you are or how much of a deal you can provide. In the early stages of a company overhead is death. I want to keep overhead as low as possible to extend runway as long as possible.