Josaphat Valdivia is Senior Software Engineer currently in the market for his next opportunity. People tend call him “Jos” (pronounced /‘dʒos/), for short.

Josaphat is a proficient software developer, leveraging good Software Engineering practice in all of his projects. He is most proficient in C++ and C, has a working knowledge of Python, and knows enough C#, Java, Rust, and go to break builds. He can grok shell scripts, has experience programming for the web using technologies such as PHP, ASP.NET, and Javascript. He occasionally likes to mention that “Spanish is like a first language” to him because he is bilingual. Though his proficiency in English surpassed his Spanish after years of English-only schooling.

Josaphat is skilled at wielding the English language, both written and spoken. He is a confident public speaker and is adept at giving engaging presentations on technical topics.

Over the last 15 years of college-level coursework and on-the-job experience, Josaphat has been exposed to a wide range of development tools and technologies, including Matlab and Octave, robotics, CSS, and GNU Assembler for Cortex-M ARM architectures. He uses GNU/Linux as his primary development environment and is a mostly-former MS Windows user. He is proficient with git as a VCS and knows how to leverage GNU/Linux as an integrated development environment. He mostly uses emacs for development. His primary editor used to be vim (with a few additions). He still occasionally uses vim, usually for quick editing of things like config files.

Josaphat had some exposure to computer graphics while at RIT where he learned about the fundamentals of the subject using SDL and OpenGL. He will with some regularity fail at game design and development using SDL, OpenGL, and frameworks like XNA and Monogame; the efforts usually peter out due to the sheer effort required to really build anything fun. He is stubbornly satisfied with having learned a bit more about game design and development with each foray.

Josaphat likes to use org-mode in emacs for digital notes. For writing formal documents or anything that might actually make its way onto paper, he likes to use LaTeX. He’s also familiar with conventional productivity suites including Microsoft Office, LibreOffice, and Google’s suite.

Josaphat likes to play guitar in his free time. With some regularity, he creates some experimental software. Much of it finds its way onto his GitHub Page, though recently he’s been trying to use sourcehut (sr.ht/~jos) more. Almost none of it is of practical use.

Professional History

Josaphat graduated from RIT Bachelors of Science in Computer Engineering (Software Engineering option) in May 2015.

As part of his degree, he did a co-op with Brand Networks over the winter of 2012 into spring of 2013. There he worked as a full-stack developer on the now-defunct American Express website, OpenForum.com (archived May 2013), built on PHP and Wordpress.

In June of 2014, Josaphat joined the effort to start a company initially called Cryptolabs. Before long, the company was re-named to Case Wallet and released a product called Case Wallet, a biometrically-secured bitcoin wallet implemented in dedicated hardware (product page archived July 2015) .

As part of a small team of engineers, Josaphat helped to develop the embedded software running on the Case Wallet. This included doing board bring-up, designing and developing C code targeting bare-metal ARM. Among other things, Josaphat helped developed code to integrate peripherals over serial interfaces (UART, SPI, I2C), including a fingerprint scanner, an e-ink display, and a 2G modem.

This was the best way to begin a career as a software developer. By working on bare-metal code, Josaphat had to learn how to write production quality software in an environment not dissimilar from the dawn of modern computing.

After production of the wallet, focus shifted to development a biometrically-secured, continuously-authenticated wearable smart-ring which eventually came to be called Token Ring. The company was renamed Token to match the new direction.

When focus shifted to Token Ring, Josaphat took on the role of a Software Architect and developed the architecture underpinning the software for the wearable. He advocated for use of modern C++ over C for embedded software, developed automated testing infrastructure which included Jenkins pipelines, developed and coached the team on techniques for unit testing code on embedded systems, and more, all in addition to being a core contributor to the embedded software itself.

In 2019, Josaphat decided to leave Token and joined REDCOM as a Software Engineer developing Sigma, a unified telecommunications platform integrating open technologies such as SIP and XMPP. His largest contributions there were developing a subsystem to bridge communications between push-to-talk radios and SIP-based phone infrastructure, as well as the backend of a new switchboard-like feature which allows an operator to patch together different lines in the system into ad-hoc groups.

Josaphat did about 6 months of light contract work on the development of ARM-based NFC payment systems, using NXP libraries and FreeRTOS.

In May 2022, Josaphat joined Datto as a Senior Software Engineer working on BCDR Agents. The job was unfortunately not a great fit for him, especially after the company was acquired, so he departed after just about 6 months. During that time he made some contributions improving the design and security of the agents software.

In November of 2022, Josaphat joined Glowforge as a Senior Embedded Software Engineer. He contributed to the development of firmware for Glowforge Aura. He led adoption of CMake as part of unifying diverging codebases, integrated GoogleTest, and other work to improve builds and tests. And he contributed significantly to integrating Glowforge Aura with the Personal Air Filter using BlueZ.

In Februrary of 2024, Josaphat’s position was eliminated as part of a company-wide restructuring at Glowforge. He is currently searching for the next opportunity in Systems Programming. His career has mostly focused on lower-level C and C++ development, in particular on embedded systems, but he prefers to be a generalist who brings a wide breadth of experience to problem solving.

In the meantime, he intends to dedicate some time to a few side-projects. Some of it might even end up on the blog!

Around the Web

Josaphat has some presence on various corners of the web, including Mastodon (fosstodon), sourcehut, LinkedIn, GitLab, GitHub, Twitter, and here on josaphat.co.

Resume

For a more succinct (and arguably less interesting) version of this document, download Josaphat’s resume as a pdf.