Jobs / iOS Software Engineer (Merpay)
Jobs at Mercari

iOS Software Engineer (Merpay)

Mercari Tokyo
EN: basic
JP: business
Employment Type
Full time

Job Description

We are looking for a professional iOS engineer to work on everything from planning to development for Merpay’s new payment and finance services, based on the company’s mission of “building trust for a seamless society.”

At Merpay, each business area is organized into a unit called a program. Each program has several iOS engineers and promote our respective businesses.

In terms of technologies, our development uses architecture based on MVVM for UIKit, and Redux inspired architecture for SwiftUI.

We work on implementation of unit tests and UI tests, while also working to constantly test these with CI and improve coverage. While naturally the team is involved with developing features for projects, our company culture encourages engineers to proactively improve development processes, automate processes using CI, and other tasks. We believe that this culture allows our software engineers to improve their abilities not only in iOS, but in many other domains as well.

Aside from that, we also encourage and look very favorably on external output. This includes:

  • Speaking at conferences both in Japan and abroad, such as AltConf, iOSCon, try! Swift, and iOSDC.

  • Writing for the Mercari Engineering Blog

  • Contributing to open source software (OSS)


  • Design/develop new Merpay features and improve existing features

  • Work on development as a team, collaborating with product managers, designers, backend engineers, and QA/testing engineers

  • Improve code quality and upgrade the development environment

  • Review team members’ code

  • Introduce new iOS related technologies and tools by creating prototypes and POC

Technical Environment

  • SwiftUI/Combine/UIKit

  • Protocol Buffers

  • Bazel

  • CircleCI / GitHub Actions

Bold Challenges

  • Bring Japan’s leading smartphone payment app to the masses quickly and without sacrificing quality. This will require polished development skills, knowledge of general security measures for finance/payment services, and knowledge of mobile application-exclusive security.

  • Manage members from diverse backgrounds, with different languages, genders, and nationalities.


Required Experience

  • A strong, shared belief in the Mercari Group and its companies' missions and values

  • Passion for finance-related business

  • Experience using Swift to develop native applications for iOS

  • Knowledge regarding standard iOS libraries and frameworks

  • Experience developing applications on a team

Preferred Experience

  • Experience developing and operating native apps with large user bases

  • Knowledge of performance optimization

  • Extensive knowledge regarding UI development using SwiftUI and UIKit

  • Experience in/understanding of the latest trends in architecture design

  • Extensive knowledge of writing testable code

  • Experience in process and release automation

  • Experience working with Bazel build system

  • Experience contributing to OSS

  • Ability to communicate in English

Screening Criteria

  • Has a strong, shared belief in the Mercari Group and its companies' missions and values

  • Capable of going bold and possessing a strong sense of responsibility in regards to their work

  • Proactive and capable of thinking independently for the good of the team

  • Possesses excellent communications skills which can push organizations and projects forward

Technical Assessment Criteria

  • Development skills matching technical items named in “Required Experience”/”Preferred Experience” above

Language Requirements

  • English: Basic (CEFR - A2)

  • Japanese: Independent (CEFR - B2)

About the Company

Mercari is a Japan-based company with the mission of “creating value in a global marketplace where anyone can buy & sell.” Having continuously worked toward this goal since our founding in 2013, we are now transforming from a startup into a global player. While this transformation brings its own specific set of challenges, we believe that solving them one after another will allow us to fully achieve our mission. Are you interested in working together to take on these exciting challenges?

Employment Status


  • Probationary period: First 3 months after joining the company. (During this period your contract conditions will be the same as that of a permanent employee.)



  • Smoking is prohibited within our offices

  • Mercari has introduced a work style policy called “Your Choice.” Each member is free to choose whether they want to work in the office or work fully remote. *Exceptions made for certain kinds of work.

Work Hours

  • Full flextime (no “core time” or “flex time”)
    *Does not apply to all positions


  • Two days off per week (as well as national holidays, New Year's break, etc.)

  • Paid leave, congratulatory and bereavement leave, relax days, sick leave


  • Annual salary paid in 12 monthly installments (including fixed overtime allowance)

  • Based on skills, experience, and abilities

  • Reviewed twice a year


  • Complete health and social insurance

  • Incentive program

  • Support systems, including those that benefit the employee’s family members
    *See this page for details.


  • Relocation support

  • Language learning support

  • Translation/interpretation support