This role involves leading the design, development, and maintenance of mobile applications for Proof, collaborating with cross-functional teams and optimizing app performance.
Proof is the world's first identity-assured transaction management platform and we are on a mission to digitize trust for all of life’s most critical transactions. Developed by the same market leaders and experts who brought notarization online with Notarize℠, Proof offers trust in a digital world by verifying identities and securing transactions to protect businesses and their customers. Since 2015, we’ve completed many of the world’s first digital commerce transactions, including the first online real estate closing, online mortgage closing, online auto sale, and online will and we're still just getting started!
We are looking for an experienced mobile application engineer to build, enhance and maintain Proof mobile applications.
What you will do as Senior Mobile Application Engineer:
- Lead design, development, and maintenance of Proof mobile applications and SDK’s for Android and iOS
- Proactively drive all phases of mobile app development, from ideation to release to tracking and analyzing the impact of shipped features
- Collaborate cross-functionally with designers, developers, QA engineers, and product managers
- Work with existing and new vendors providing components, SDK’s and API’s enabling Proof mobile apps
- Provide leadership and critical input on advancing technical standards and best practices as appropriate
- Contribute to continuous improvements of mobile app automation, unit tests, CI/CD
- Triage bugs, track software defects, and ensure their timely resolution
What we're looking for:
- Advanced expertise in Android and iOS application, SDK development
- Experience with NFC, applied cryptography (PKI), wallets is a plus
- Proven ability to work with both established, legacy applications and new, greenfield proof-of-concepts.
- Deep knowledge of mobile app lifecycle, app store deployment, and distribution
- The ability to work autonomously and own problems from end to end; bias towards action and solutions
- Proven ability to troubleshoot and optimize consumer facing mobile applications
- Effective communication and active listening skills, with a thoughtful, collaborative approach to problem-solving
- Full ownership of the code you write, from the technical design through to production
Our tech:
- Proof platform’s back-end is Ruby on Rails, Postgres SQL, Redis, hosted on AWS. Our front-end apps are built with React, GraphQL, Apollo and TypeScript.
- Proof mobile apps are built with Kotlin and Swift, using GraphQL to integrate with the back-end. Our mobile apps utilize a blend of modern and established frameworks: Jetpack Compose and XML layouts for Android, and SwiftUI and UIKit for iOS.
Our engineering culture:
- Proof has a strong focus on mentorship, with regular 1:1s, reviews, and check-ins to ensure that you are learning & growing as an engineer. Your manager will help you set personal goals, support your learning, and track your progress against those goals, to encourage you in the growth of your career, wherever it may take you.
- You'll be part of a small, cross-functional team with a highly collaborative process that values thoughtful communication, not just with other engineers but with all parts of the organization.
- We’re a startup with big plans, and there’s so much to do. Whether it’s an antiquated legal process, an edge-case user interaction, a quirky piece of code, or unnecessary friction in the CI/CD process, we show up every day with the goal of digging in and leaving something better than we found it.
Our Proof Pillars:
- Pave the Way: When obstacles arise, we break through barriers with passion and perseverance. We lead with creativity and forward-thinking. We aim to set new standards and shape the future in a repeatable, scalable way so the path to success is easier for our team to follow.
- Own It: We embrace the responsibility that comes with supporting life's most important transactions. When a problem arises we relentlessly pursue the solution with a 'Yes before no' attitude. Because every problem and every transaction is treated like it's our own.
- Act with Integrity: We are in the business of building trust and it is at the core of everything we do. We are honest and transparent with our customers, each other and ourselves. If we make a mistake, we own up to it right away and do what it takes to make it right. Our dedication to security and compliance is key to earning trust, fighting fraud and ultimately, our success.
- Play to Win: We believe excellence is about always striving to be better so when we get it wrong, we iterate, we learn and we grow. We know we can only go so far alone, we're better together and collectively, we win!
Here are some of our great benefits:
- Medical, dental, and vision benefits
- Life insurance, long and short-term disability coverage
- 401k Plan with a 4% match, beginning on your hire date
- Unlimited Sick and Vacation time
- 14 paid company holidays
- 2 company Chillax weeks (Summer & Winter)
- 12 weeks of paid parental leave
- 4 week sabbatical after 5 years of continuous full time employment
- Health Reimbursement Arrangements for fertility and gender affirmation
- Lunch on Proof through Grubhub credit
- Monthly work from home stipend
- Professional development credit
- Monthly reimbursement for Wellness
- And more!
This position will be posted and accepting applications through December 19, 2025.
Proof uses Identify, our identity verification tool, to confirm that individuals engaging with Proof at any stage correspond to a real identity. It’s a quick security step that helps keep the process safe for everyone. Identify is used solely for identity verification and fraud prevention and is not used to assess employment eligibility or qualifications.
Proof is committed to building an inclusive environment for people of all backgrounds and everyone is encouraged to apply. We are an equal opportunity employer and do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.
Top Skills
Apollo
AWS
GraphQL
Jetpack Compose
Kotlin
Postgres Sql
React
Redis
Ruby On Rails
Swift
Swiftui
Typescript
Uikit
XML
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