David Chou

Umbo is an A.I. startup that leverages machine learning and cloud technology to build autonomous video security systems for businesses. As a founding engineer, I participated in the whole architecture design and product implementation from scratch. As an engineering team lead, I mentored, sponsored and supported my members by shaping Umbo engineering culture. As a cloud architect, I committed to optimize infrastructure and improve work flow.

• Team management

  • Led engineering team of 8 members

    My responsibilities included OKR planning, regular 1-1 feedback, mentoring, sponsoring, and hiring. I committed to build a responsible, transparent and keep-learning engineering team.

  • Focused on team-wise productivity improvement

    Standardized the development flow, introducing CI/CD and unit testing, adopting Infrastructure-as-code, and shaping DevOps culture in the team.

  • Cross-team collaboration

    Frequently co-worked with different teams, such as Design, Product and Sales, to help them from different approaches, such as studying competitor, discussing product roadmap, joining customer concalls, etc.

• Architect and engineering

  • Low latency video streaming service (Golang)

    Designed and developed Umbo’s video streaming service on a large scale across multiple regions. It was the core architecture of Umbo and served more than 7500 cameras with below 3 seconds latency.

  • IoT messaging service (Golang)

    Developed and maintained the core messaging service that provided real-time communication across devices by WebSocket and served all Umbo’s cameras across 4 different regions.

  • Launch a new product - Event Filter (Golang)

    Involved in the completed product lifecycle from market research, competitor studying, product design, development, and launching. Engineering-wise, I implemented 2 gateway services (SMTP and HTTP) and deployed to ECS Fargate with Terraform. As a result, it reduced 83% of false alarms for customers and boosted Umbo’s monthly recurring revenue (MRR) by 230%.

  • Firmware applications development (C/C++)

    Involved in firmware architecture design and development. Designed a flexible cross-platform firmware architecture that helps us to deliver different camera models efficiently.

• Infrastructure and process optimization

  • Standardlized production service deployment

    Standardlized a consistent service deployment by using AWS ECS Fargate and Terraform. Different services could use the same way for secret management, log collection, monitoring, etc. It drastically reduced the operation loading and speeded up the launch of new services by 300%.

  • Cross-services tracing solution

    Led and supported the team to build a cross-services tracing by leveraging NewRelic tracing service. It gave us a clear view of end-to-end latency, and we built monitoring and alerting based on the metrics.

  • Optimize AWS infrastructure costs

    Led and supported the team to continuously optimize AWS costs. I regularly reviewed AWS cost analysis and proposed different approaches, including EC2/Fargate Spot and ARM instance adoption, NAT and cross-zone traffic reduction, S3 lifecycle optimization. As a result, we reduced 54% AWS system cost under the same business scale.

  • Internal infrastructure administration

    As an AWS architect of the team, I managed shared resources, such as IAM, VPC, purchasing RI/saving plan, building common AMI. I migrated internal services (e.g., Grafana, Sentry, ETL jobs) to EKS by using Terraform and Helm. I also optimized the performance of the log collection pipeline by fine-tuning Fluentd aggregator and ElasticSearch.

Joined the new industrial control system (ICS) solution team in the early stage, and experienced the whole product development cycle from planning, development, shipping, and maintenance.

• Trend Micro Safe Lock
  • A standalone system lockdown software for fixed-function devices.
  • Developed the backend REST API service.
• Trend Micro Portable Security
  • A malware scanning and cleanup tool for standalone PC or closed system.
  • Designed and developed this product from the fundamental core module to user interface.

I worked on video decoder and new features development for H.264, MPEG2, and VC1. The video decoder is the core module in the company and has been integrated into all products.

• Maintained the quality of video decoder module.
• Performance tuning with SSE/Intrinsic SIMD optimization.
• Developed hardware decoding for H.264, Motion JPEG decoding using hardware acceleration.