About Appier 

Appier (TSE: 4180) is an AI-native Agentic AI as a Service (AaaS) company that empowers businesses to create value through cutting-edge AdTech and MarTech solutions. Founded in 2012 with the vision of “Making AI Easy by Making Software Intelligent,” Appier helps businesses turn AI into ROI through its Ad Cloud, Personalization Cloud, and Data Cloud—each powered by Agentic AI that enables autonomous, adaptive, and real-time decision-making. Today, Appier operates 17 offices across APAC, the US, and EMEA, and is listed on the Tokyo Stock Exchange. Learn more at www.appier.com.

About the role

Software engineers at Appier build a wide range of platforms and services that interconnect data and AI with our customers and users. As a Senior Software Engineer, Backend Development at Ad Cloud Platform Team, you will design and build scalable and performant backend architecture, own and drive the technical roadmap for sizable projects or services, mentor junior engineers, and facilitate high performance agile teams collaborating with cross-functional teams.

About you 

[Minimum Qualifications]

• 2~4 years of hands-on experience in backend software development, particularly with high-performance, high-concurrency systems.
• Proficient in one or more of the following languages, Python is preferred.
• Strong experience in system design and architecture for scalable and distributed systems, especially within a Linux environment.
• Good understanding of Network API Design (e.g., RESTful APIs, gRPC, GraphQL) and experience with message queues (e.g., Kafka, Pub/Sub) for data pipelines.
• Solid knowledge of SQL/NoSQL databases (e.g., MySQL, MongoDB, Redis, ClickHouse, PostgreSQL) and experience with database optimization and scaling strategies.
• Familiarity with DevOps practices, including CI/CD pipelines, Docker, Kubernetes, and cloud platforms (AWS, GCP, or Azure).
• Experience with observability tools (e.g., Prometheus, Grafana) and robust monitoring and alerting implementation.
• Highly proficient in AI-assisted development workflows, with hands-on experience leveraging tools such as Cursor, Claude Code, Gemini, or equivalent in day-to-day engineering.
• Solid understanding of agentic coding paradigms, including building or working within multi-step, tool-augmented AI development pipelines.
• Proactive, excellent problem-solving skills, and strong communication in a cross-functional team setting.

[Preferred Qualifications]

• BS/MS degree in Computer Science or a related field.
• Demonstrated ability to develop complex business features with PM, QA, and front-end engineers.
• Experienced in promoting backend architecture upgrades or improving development processes.
• Exposure to context engineering or AI harness engineering, including designing prompt pipelines, managing LLM context windows, or building structured AI orchestration layers.
• Experienced in building SDKs and applications for iOS or Android.

#LI-AK1

About Appier 

Appier is a software-as-a-service (SaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information.

About the role

We're looking for an experienced data engineer to build and scale our data infrastructure. You'll work on mission-critical systems that power our data-driven decision making, designing robust pipelines and optimizing distributed platforms that process massive datasets.

Responsibilities

• Design, develop, and maintain production data pipelines processing hundreds of terabytes of data daily across distributed systems
• Build, manage, and optimize large-scale data platforms including Spark clusters, Kafka clusters, and related big data infrastructure
• Develop and operate data warehouse systems and ETL pipelines for data collection, processing, storage, and analytics
• Profile and tune performance of critical components to optimize throughput, reduce latency, and improve resource efficiency
• Establish architectural foundations and engineering best practices for the platform
• Design frameworks and tooling to streamline software development, deployment, monitoring, and observability
• Provide technical expertise and guidance on big data system design, performance optimization, and scalability challenges

About you

[Minimum qualifications]

• BS/MS degree in Computer Science or related technical field
• 2+ years of hands-on experience building and operating large-scale distributed systems
• Proficiency in Java and/or Scala for production-level development
• Proven experience building ETL pipelines and data processing workflows using Apache Spark
• Experience managing and optimizing data lakes or data warehouses at scale
• Ability to work independently and adapt quickly in fast-paced, dynamic environments
• Self-motivated learner who takes ownership, manages multiple priorities effectively, and thrives in collaborative team settings
• Experience deploying and managing infrastructure on public cloud platforms (AWS, GCP, or Azure)

[Preferred qualifications]

• Proficiency in Python and/or Golang for building production systems
• Experience profiling and optimizing JVM performance for high-throughput applications
• Hands-on experience managing and operating data platforms such as Hadoop, Kafka, Flink, Hive, Trino, Presto, or ClickHouse
• Knowledge of modern open table formats including Apache Iceberg, Delta Lake, or Hudi 
• Active contributions to open source projects (please include your GitHub profile if applicable)

#LI-AK1

Join Proton and build a better internet where privacy is the default

At Proton, we believe that privacy is a fundamental human right and the cornerstone of democracy. Since our inception in 2014, founded by a team of scientists from CERN, we have dedicated ourselves to providing free and open-source technology to millions worldwide, ensuring access to privacy, security, and freedom online.

Our journey began with Proton Mail, the largest secure email service globally, and has since expanded to include Proton VPN, Proton Calendar, Proton Drive, and Proton Pass. These tools empower individuals and organizations to take control of their personal data, break away from Big Tech’s invasive practices, and defeat censorship. Our work impacts hundreds of millions of lives, from activists on the front lines defending freedom to leaders in governments protecting sensitive information. In some cases, Proton’s services have even been instrumental in saving lives by enabling secure and private communications in high-risk situations.

Proton is a profitable company that does not rely upon VC funding, supporting over 100 million user accounts with a growing team of over 500 people from over 50 different countries, from the world's top companies and universities. We value intelligence, learning potential, and ambition in our hiring process. Adaptability is key as we navigate uncharted territories and redefine how business is conducted online.

Hiring at Proton is highly selective, with less than 1% of candidates hired. We believe smaller teams of exceptional talent will always prevail over larger teams with lower talent density. You will have the opportunity to work with many of the world's top minds in their fields, ranging from former international math and science olympiad winners to chess champions.

We have a global mindset and big ambitions but remain a start-up at heart. We value empowerment and flexibility and keep our structure flat to keep moving fast and avoid unnecessary politics. Tired of blending into the crowd? Join us and do work you can truly be proud of. Check our open-source projects here!

Purpose of the role

MSA is a highly multi-disciplinary group started in 2019 to tackle difficult mail delivery, spam, abuse, and account security problems that impact the Proton ecosystem. We built sophisticated systems from scratch that combine human intelligence and machine learning to make tens of millions of realtime or asynchronous decisions each day. Our custom systems have reduced spam filter misclassifications by over 60%, blocked millions of abusive bulk signups, protected hundreds of thousands of users from account compromise by attackers, and mitigated hundreds of DDoS attacks. In the last few years, we have also been building complicated new products, including launching Wallet, Lumo AI, and Meet. We are the main group at Proton working on AI. In order to move fast with limited resources, we are organized into autonomous teams responsible for the whole system, with expertise across infrastructure, data storage, backend, web and mobile apps, machine learning, security and operational excellence. We are looking for humble, mission-driven, systems-thinking people who want to make a big impact in a startup environment.

What you will do

MSA builds and operates many services responsible for different domains. You will:

• work with other engineers and analysts to design, build, and operate these systems
• work on special user-facing features involving frontend and backend software development
• You will have the opportunity to play Product or Project Managers roles and lead the whole planning and development process
• be responsible for the operational excellence of the systems/features and their interaction with other systems
• You may work on MSA's custom systems written in Python or on the main Proton API written in PHP or on Proton Web apps written in React or even on native iOS and Android mobile apps

Job requirements

• Deep experience with backend development (Python, PHP, or Go)
• Experience with frontend design and development (JavaScript, React, Typescript, or jQuery)
• Experience building complex production systems
• Experience with data processing and storage (MySQL, MongoDB, Redis, Kafka, Elastic, Ceph, ClickHouse)
• Able to work autonomously and lead the whole development process, from design to QA
• Experience with AI tools and AI agents
• Excellent English communications, both written and spoken

Bonus points for: 

• experience with machine learning and real-time prediction systems
• experience with iOS or Android app development
• experience with managing Linux servers, including infrastructure as code (Puppet, Ansible) and containerization

What We Offer

• Office First: Collaboration is easier and more effective in person, which is why we have offices in Geneva, Zurich, Prague, Barcelona, Paris, London, Vilnius, Skopje, and Taipei. You can also enjoy working from home up to 30% of the time, while enjoying great company during our three core days in the office. 
• Technology: We provide all the devices and software you need to excel in your role, ensuring you have the best tools at your disposal to achieve your goals.
• Food: Lunch and snacks are provided by Proton every day at our offices.
• Transport: We will always support our employees with transport costs through subsidizing public transport, bike allowances, or parking spaces based on your office location.
• Stock Options: At Proton, we are all owners of the company and you get stock options when you join us.
• Flexible Working: You can define your own working hours as long as it works with team meetings.
• Learning and Development: We are committed to your professional growth. Proton offers various learning opportunities, including training programs, conferences and events, and continual learning.
• Employee Benefits: Comprehensive health insurance plans, competitive retirement savings options, generous vacation and leave policies, and wellness programs.
• Work that Matters: Proton is a community-first organization, started with the support of a crowdfunding campaign and built with community input. To this day, Proton’s only source of revenue is user subscriptions. Over 100 million people trust and support Proton, and we put our users and community first in everything we do. Read more about our impact here.

Our Commitment to Diversity and Inclusion

At Proton, we believe diversity drives innovation and strengthens our mission to provide privacy as a default for all. We are committed to fostering an inclusive environment where all individuals, regardless of race, ethnicity, gender, age, sexual orientation, physical ability, or socio-economic background, feel valued and empowered. We strive to create equal opportunities, promote open dialogue, and support continuous learning to ensure every voice is heard and respected.

If you need any extra support or reasonable adjustments during the hiring process, please let your talent partner know.

Candidate Privacy Notice

When you apply for a position, refer a candidate, or are considered for a role at Proton Technologies AG (Proton, we, us, or our), your information is stored in Greenhouse, in accordance with their Service Privacy Policy. This information is used to evaluate your suitability for the posted position. We also retain this information for consideration for future roles that you may apply for or that we believe may align with your background and skills.

If we no longer have a legitimate business need to process your information, we will either delete or anonymize it. Should you have any inquiries about how we use or manage your information, or if you wish to access, correct, or delete your data, please contact our privacy team at careers@proton.ch.

Proton does not accept unsolicited resumes from any sources other than directly from candidates. We will not pay a fee for any placement resulting from an unsolicited offer, even if the candidate is subsequently hired by Proton.

To learn more about our privacy policy, please visit our privacy policy page.

#LI-ONSITE

Realize your potential by joining the leading performance-driven advertising company!

As a Senior Backend Engineer on the Backend team in our Taipei Office, you’ll play a vital role in building the foundational systems that power content understanding for the entire organization. You will create the robust backbone that enables every team to leverage Generative AI. You will operate with the agility of a startup to deliver powerful, scalable solutions and directly shape how the company innovates with AI.

To thrive in this role, you'll need:

• 7+ years of hands-on coding experience in Java or similar object oriented programming languages.
• Deep understanding of strong Computer Science fundamentals: object-oriented design, data structures, applications programming and multi threading programming.
• Experience with SQL and No-SQL, ex: MySQL, Vertica, Cassandra, Google BigQuery.
• Experience with common frameworks: Spring, Maven, Kafka, Apache Spark.
• Proven experience in building and managing data pipelines and distributed systems.
• Thorough understanding of backend integration concepts and technologies such as API, web services, message queuing, and security practices.
• Quick and self-motivated learner with strong problem-solving skills and the ability to troubleshoot complex issues.
• Excellent communication skills and the ability to work collaboratively in both team and cross-timezone environments.

Bonus points if you have:

• Well understanding of common design patterns and engineering best practices.
• Familiarity with containerization and orchestration technologies like Kubernetes and Helm.
• Experience with workflow automation tools like Apache Airflow.
• Knowledge of CI/CD tools such as Jenkins.
• Familiarity with modern development practices such as Agile methodologies and DevOps principles.

How you'll make an impact:

As a Senior Backend Engineer, you will:

• Technical Leadership: Acting as a key technical leader for the group, guiding the architecture and design of complex, business-critical systems.
• Hands-On Excellence: Driving development by being hands-on, personally writing code for the most complex and critical system components and setting a high bar for code quality and best practices.
• Strategic Scalability: Driving the technical strategy for building highly scalable and reliable solutions to process massive datasets and ensure system stability.
• Democratizing AI: You will architect the centralized access layer that allows every service in the organization to integrate with Large Language Models safely and efficiently.
• Powering the Content Engine: You will own the high-throughput content data infrastructure that ingests, processes, and serves the fundamental data powering our recommendations.
• Automating Quality: You will co-own the pipelines responsible for automated Ad Quality, ensuring millions of recommendations meet strict safety standards without human intervention.
• End-to-End Ownership: You will take full responsibility for the lifecycle of your services—from initial architectural design and hands-on coding to deployment, monitoring, troubleshooting, handling incidents and ensuring production reliability.

Why Taboola?
If you ask Taboolars what they love about working here, they'll tell you that they've been empowered to realize their full potential while growing and learning from and with smart and talented people. They'll also share more about:

• Adam Singolda, Taboola Founder and CEO says; "You can copy anything from another business but you can't copy a company's culture.
• Well-being: Enjoy comprehensive benefits, a fully stocked kitchen, and location-specific perks.
• Flexibility: We offer a hybrid work schedule with 3 days in-office with an option to come in more often if desired.
• Work with some of the biggest names: We work with some of the biggest names in the business. Our publisher partners include Yahoo, Conde Nast, Fox Sports, NBCU, ESPN, CBS, and E! Online. Our advertiser clients include Wells Fargo, Honda, Pinterest, Expedia and Honda.

Ready to realize your potential?
Taboola is an equal opportunity employer and we value diversity in all forms. We are committed to creating an inclusive environment for all employees and believe such an environment is critical for success. Employment is decided on the basis of qualifications, merit, and business need.

Learn more about #TaboolaLife on LinkedIn, Facebook, Instagram, X, YouTube, & the Taboola Life Blog.

About Taboola
Taboola empowers businesses to grow through performance advertising technology that goes beyond search and social and delivers measurable outcomes at scale. Taboola works with thousands of businesses who advertise directly on Realize, Taboola's powerful ad platform, reaching approximately 600M daily active users across some of the best publishers in the world. Publishers like NBC News, Yahoo, and OEMs such as Samsung, Xiaomi and others use Taboola's technology to grow audience and revenue, enabling Realize to offer unique data, specialized algorithms, and unmatched scale.

#LI-Hybrid

#LI-MT1

About Appier 

Appier is an AI-native Agentic AI as a Service (AaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information. Our EDP team builds core data backend capabilities that power critical product experiences across ingestion, profile processing, and serving.

About the role

We are hiring a Senior Software Engineer, Data Backend to design and operate production-grade data backend systems at scale. This role combines backend service engineering and data platform engineering, with strong focus on reliability, performance, and cost efficiency in a cloud-native environment.

You will work on high-throughput APIs/services in Go, as well as data processing and workflow components in Python/Spark/SQL, partnering closely with product, platform, and data teams.

What you will do

• Design, build, and maintain backend services and data platform components.

• Develop and optimize streaming and batch data workflows.

• Improve reliability and operability (monitoring, alerting, incident prevention/recovery).

• Improve data quality and consistency through schema/contracts and validation mechanisms.

• Diagnose and resolve production issues across service and data layers.

• Drive performance and cost optimization initiatives for large-scale workloads.

• Collaborate across teams to deliver roadmap milestones.

• Mentor engineers and contribute to engineering standards and review culture.

About you

[Minimum qualifications]

• 6+ years of software engineering experience in backend/data-intensive systems.

• Strong proficiency in Go (required).

• Strong proficiency in Python (required).

• Strong proficiency in SQL (required).

• Hands-on experience with distributed data systems (e.g., Kafka, Spark/Databricks).

• Experience operating services/pipelines in cloud production environments (GCP preferred).

• Solid understanding of reliability practices: observability, on-call, incident response.

• Strong communication and ownership; able to drive ambiguous projects to completion.

[Preferred qualifications]

• Experience with Databricks/Delta Lake/Lakehouse architectures.

• Experience with Kubernetes/GKE and Terraform/IaC.

• Experience with data governance (lineage, access control, PII handling).

• Experience with identity/profile systems (entity resolution, merge logic).

• Experience with FinOps/cost optimization for platform workloads.

• Scala/Java experience for Spark ecosystem optimization is a plus.

[Language]

Fluent in English.

Why join us

• Work on high-impact, business-critical data backend systems.

• Own real production outcomes across scale, quality, and cost.

• Collaborate with strong cross-functional teams in AI + data.

• Grow technical leadership while staying hands-on.

Open to overseas candidates/Visa Support
This position is open to based in Taipei, Taiwan or Tokyo, Japan. For international candidates, Appier's Japan office provides visa sponsorship to ensure a smooth transition to Japan.

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About Appier 

Appier is an AI-native Agentic AI as a Service (AaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information.

About the role

Appier's Playable Ads team (https://www.appier.com/en/blog/what-is-playable-ads)  builds AI-powered playable and video ad experiences that drive dramatically higher engagement and conversion for the world's leading apps and games. We're looking for a Senior Backend Developer with deep expertise in distributed systems and modern backend architecture to design and build the scalable, high-performance services behind these experiences — from creative generation pipelines to the infrastructure that brings our ML models to production. You'll work across microservices, messaging systems, data persistence layers, and system performance optimization, while partnering with ML scientists on MLOps workflows to continuously ship and serve new model versions to end users. You'll also collaborate closely with frontend engineers and product managers to deliver seamless, cross-functional outcomes.

If you're passionate about building backend systems that operate at scale, thrive in cross-functional teams, and want your code to directly power AI-driven ad experiences reaching millions of users, we'd love to talk.

What You'll Work On

• Architect and develop robust, scalable backend services and APIs using ASP.NET Core, owning sizable projects from system design through production operation.
• Design efficient database schemas and optimize data access logic across SQL and NoSQL data stores.
• Implement message-driven communication with high reliability and fault tolerance.
• Partner with ML scientists to build and maintain MLOps pipelines — including model versioning, deployment, serving, and monitoring — ensuring new models are reliably delivered to production.
• Lead system designs, drive technical roadmap decisions, and provide guidance to team members.
• Proactively identify performance bottlenecks, profile critical components, and implement scalable solutions.
• Own and continuously improve system observability, incident management, CI/CD pipelines, and deployment workflows.
• Explore and integrate AI-assisted development tools and emerging technologies to boost team productivity.
• Participate in on-call rotation to ensure product reliability and scalability.

What We're Looking For 

[Minimum qualifications]

• Proficiency in C# and ASP.NET Core, or experience with other object-oriented languages (e.g., Java, Go) with willingness to cross-train in the .NET stack.
• Proven experience in distributed systems, microservice architectures, and designing scalable backend systems.
• Strong expertise in PostgreSQL, MongoDB, or equivalent SQL/NoSQL databases, with hands-on experience in ORM frameworks such as Entity Framework Core.
• Advanced knowledge of message broker systems such as RabbitMQ, Kafka, or NATS.
• In-depth understanding of IO-bound operations, threading, parallelism, and asynchronous programming.
• Practical experience with Docker, container-based deployment workflows, and cloud platforms (AWS, GCP, or Azure).
• Hands-on experience with CI/CD pipelines, observability tooling, and production operational practices.
• Demonstrated ability to write clean, well-documented code and solve complex problems analytically.
• Clear communicator who can explain technical decisions to both technical and non-technical stakeholders and enjoys working in a fast-paced, collaborative environment.
• Proficient in using LLM-powered development tools (e.g., GitHub Copilot, Cursor, ChatGPT) to accelerate productivity.

[Preferred qualifications]

• BS/MS degree in Computer Science or a related field.
• Experience with MLOps practices such as model serving infrastructure, A/B testing frameworks, or ML pipeline orchestration tools.
• Leadership experience such as mentoring junior engineers, leading code reviews, or facilitating agile processes.
• Experience with performance profiling and debugging tools, high-performance network services, or FFI integrations for performance-critical components.
• Solution-oriented mindset with a focus on system sustainability, and willingness to explore emerging technologies into backend systems.

[Language]

Fluent in English, Japanese language proficiency is not required.

Open to overseas candidates/Visa Support
This position can be based in Tokyo, Japan or Taipei, Taiwan. For international candidates, Appier's Japan office provides visa sponsorship to ensure a smooth relocation transition to Japan.

#LI-AK1

About Appier 

Appier (TSE: 4180) is an AI-native Agentic AI as a Service (AaaS) company that empowers businesses to create value through cutting-edge AdTech and MarTech solutions. Founded in 2012 with the vision of “Making AI Easy by Making Software Intelligent,” Appier helps businesses turn AI into ROI through its Ad Cloud, Personalization Cloud, and Data Cloud—each powered by Agentic AI that enables autonomous, adaptive, and real-time decision-making. Today, Appier operates 17 offices across APAC, the US, and EMEA, and is listed on the Tokyo Stock Exchange. Learn more at www.appier.com.

About Ad Cloud  Serving Services Team

At Appier's Ad Cloud Team Serving Services Team, we build and maintain the critical systems that power the core of Appier's advertising technology. These systems handle massive, high-concurrency, real-time requests, and ensure the stability, low latency, and high performance of our ad delivery. Our SRE professionals are crucial in guaranteeing these services remain reliable under extreme loads, continuously enhancing product availability and performance through innovation and automation.

Responsibilities

• Lead the design and development of scalable, high-performance, and reliable backend services for real-time ad recommendation, data serving, and core ad tech infrastructure.
• Drive technical roadmap and ownership for sizable projects, ensuring the delivery of robust and efficient solutions within the Ad Cloud ecosystem.
• Optimize critical system components for latency, throughput, and resource utilization, including database interactions (e.g., MongoDB sharding, ClickHouse optimizations) and network architecture.
• Enhance system observability, incident management, and operational excellence by implementing comprehensive monitoring, alerting (e.g., Grafana, Prometheus), and refining production SOPs.
• Collaborate closely with product managers and scientists to translate business requirements into technical designs and ensure seamless integration.
• Champion code quality through rigorous code reviews and adherence to best practices in system design and implementation.
• Mentor and guide junior engineers, fostering their growth in backend development best practices, distributed systems, and agile methodologies.
• Actively participate in on-call rotation within the Backend team to maintain product reliability and scalability for critical serving services.
• Contribute to a culture of continuous improvement, initiating team-level technical discussions, process enhancements, and knowledge sharing.

About You

[Minimum Qualifications]

• 3-5+ years of hands-on experience in backend software development, particularly with high-performance, high-concurrency systems.
• Proficient in one or more of the following languages: Go, Python.
• Strong experience in system design and architecture for scalable and distributed systems, especially within a Linux environment.
• Good understanding of Network API Design (e.g., RESTful APIs, gRPC) and experience with message queues (e.g., Kafka, Pub/Sub) for data pipelines.
• Solid knowledge of SQL/NoSQL databases (e.g., MySQL, MongoDB, Redis, ClickHouse, PostgreSQL) and experience with database optimization and scaling strategies.
• Familiarity with DevOps practices, including CI/CD pipelines, Docker, Kubernetes, and cloud platforms (AWS, GCP, or Azure).
• Experience with observability tools (e.g., Prometheus, Grafana) and robust monitoring and alerting implementation.
• Proactive, excellent problem-solving skills, and strong communication in a cross-functional team setting.

[Preferred Qualifications]

• BS/MS degree in Computer Science or a related field.
• Demonstrated ability to refactor complex systems, improve performance metrics (e.g., latency, error rate, CPU usage), and optimize resource utilization.
• Familiarity with A/B testing frameworks and supporting customizable configurations for model iteration.
• Hands-on experience with deploying and serving machine learning models in production environments.
• Exposure to ad-tech or recommendation systems is a plus.

#LI-AK1