# SkillBox technical case study: LINE notifications greatly increased usage rate of engagement surveys, even for employees without email addresses **About this page** This page contains articles migrated from the LINE API Use Case site (closed on March 31, 2026) to the LINE Developers site. The page presents case studies of companies that have adopted the LINE Platform. Note that the content of the articles reflects the information available at the time of publication. ![HRCOM Co.](https://developers.line.biz/media/messaging-api/technicalcase/skillbox/en/skillbox-logo.png) **HRCOM Co. Ltd.** We are experts in improving employee engagement, facilitating the implementation of employee engagement surveys, including questionnaire design, analysis report creation, as well as the proposal and application of improvement measures. We also offer "SkillBox", a solution for enhancing engagement such as solving internal communication issues. ## SkillBox, a praise-based mentor system SkillBox is a praise-based mentor system that effortlessly enhances engagement. When comparing organizations with low engagement to those with high engagement, low-engagement organizations lack encouragement for employees, while high-engagement organizations offer frequent supportive feedback, such as "Nice work!", "Is there anything you're struggling with?" and "Keep it up!" SkillBox naturally creates a situation where both new employees and senior employees can frequently offer positive feedback to each other with just 1–2 minutes of interaction each week, thereby improving engagement. Specifically, new employees conduct a weekly self-review by selecting either "Task completed" or "Not completed" for each item on a predefined action list. The self-review screen also includes an optional, free text field for the new employee to share their efforts or seek advice, allowing them to report their current status to their mentor. Mentors can react to the review with stickers or comments, allowing them to easily provide the necessary follow-up as a mentor through these interactions. Through SkillBox, we aim to address the challenge of early turnover among young employees. More than 30% of university graduates leave their jobs within three years of joining a company,(\*1) and many organizations view the turnover of young employees as a serious issue. Mentor programs are one approach to addressing this challenge. They have been adopted by 48% of companies, and 70% of those companies report that the programs are effective.(\*2) However, in many cases, the burden placed on mentors—who are typically senior employees—through regular meetings and other commitments is significant. As a result, these programs are sometimes reduced to a formality at the discretion of individual teams. By utilizing SkillBox, companies can minimize the burden on mentors and ensure that the mentoring system functions properly, further reducing turnover rates. \*1: [Ministry of Health, Labour and Welfare: “Employment Status of New Graduates (March 2020 Graduates)"](https://www.mhlw.go.jp/content/11805001/001158687.pdf) \*2: [HR Research Institute: “Survey on Employee Development: New Employee Training” – Report of Findings (2020)](https://hr-souken.jp/research/2550/) ### Image ![service-image](https://developers.line.biz/media/messaging-api/technicalcase/skillbox/en/skillbox-ui-img.png) ## System overview ![System architecture diagram](https://developers.line.biz/media/messaging-api/technicalcase/skillbox/en/skillbox-system.png) ### Technical architecture of AWS-based projects We selected Amazon Web Services (AWS) as the core system infrastructure for our project. For the backend, we use Python, a programming language that allows machine learning models to be easily integrated. As the project framework, we adopted Flask, a lightweight framework that runs smoothly on both ECS and Lambda. Furthermore, we built a frontend environment in which Vue.js runs using CloudFront and S3, and a backend environment using ECS and Flask. We use Amazon Aurora as the database. ECS handles callbacks from the LINE API, while AWS Lambda executes scheduled notification processes for users via the LINE API. We use GitHub Actions for continuous integration (CI) and AWS CodePipeline for continuous delivery (CD). Since LINE is used specifically for notification purposes in this project, we use LINE WORKS and the Messaging API. ### Building response habits and contributing to lower turnover SkillBox is now being adopted even by companies whose employees do not have company email addresses. Companies that have implemented SkillBox using LINE API integrations (LINE WORKS and the Messaging API) have given it highly favorable evaluations for being simple and easy to use. For example, a real-life case is Olive Spa, which operates beauty clinics across Japan. Previously, the company supported new employees using paper-based daily reports. SkillBox has been well received as a convenient evolution of that approach. Regarding the use of personal smartphones, the company commented that "there were no issues at all when operations began, and it was smoothly accepted at the workplace", and that "we genuinely feel it is helping to prevent employee turnover". (\*4) \*4: [SkillBox case study: Olive Spa Co., Ltd.](https://www.skillbox.jp/eduken/interview006) ### Future prospects for SkillBox feature improvements We plan to continue improving SkillBox so that it becomes even more convenient to use and delivers greater results over time. One principle we emphasize internally is that the system must be enjoyable for users. This includes the functional aspects of the system, such as incorporating game-like elements through gamification, as well as operational considerations, such as how to encourage the habit of responding in a natural, low-stress way. Therefore, we believe it is important to continuously rethink how response request notifications are delivered and which devices will be used for submitting responses. In this regard, further refinement of our API integration with LINE may present additional opportunities. For example, future ideas include enabling users to submit responses on SkillBox directly via LINE Official Account, or allowing them to read comments made in SkillBox directly on the official account. While these are still conceptual at this stage, we aim to continue advancing initiatives that make SkillBox even more convenient for users. ### Requests for the LINE API LINE API offers extensive documentation, which allowed us to implement it smoothly. While at present, notifications are sent via LINE and users enter their responses on the web, we also considered enabling responses to be made directly within LINE. However, for forms that require multiple selections or inputs, the flow for canceling or editing submitted responses tended to become complex, so we decided not to pursue this approach. We also use the LINE WORKS API for notification processing. In some cases, the error messages provided limited information, making it difficult to determine the exact cause of an error or narrow it down to a single factor. ### A message for those developing new services We have been operating a service that uses the LINE API for more than two years. To date, we have encountered very few communication errors and other issues, and the service has proven to be consistently more stable than similar third-party services that we use at the same time. --- ## Related Links - [HRCOM Co. Ltd.](https://hrcom.co.jp/) - [SkillBox](https://www.skillbox.jp/)