Steven Kramer，荷兰阿姆斯特丹的开发者
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Steven Kramer

Verified Expert  in Engineering

算法开发

Location
荷兰阿姆斯特丹
Toptal Member Since
November 26, 2019

Steven has extensive experience in software development with skills in a variety of technologies gained through contributions to innovative, 高质量的项目. He prides himself on raising the quality of projects he's worked on and teams he's worked with. 不怕在新环境中从零开始项目, 也不是在项目进行到一半时突然介入以加快进度, Steven专注于提供高质量的解决方案.

用户界面(UI)DebuggingApp StoreObjective-CXcodeiOSUIKitREST APIsTestFlightSwiftAlgorithmsMultithreading后端性能ScalabilitySecurity

Portfolio

Shackle
SwiftUI、模型视图视图模型(MVVM)、gRPC、依赖注入...
fashionTrade(自由)
Xcode，后端，算法，敏捷，移动，持续集成...
TomTom (freelance)
后端，敏捷，iOS, Objective-C，移动，objective - c++， c++， UIKit...

Experience

算法- 20年后端- 20年Mobile - 20 yearsC++ - 19 years目标c - 15年iOS - 12 yearsSwift - 4 yearsSwiftUI - 1 year

Availability

Full-time

首选的环境

亚马逊网络服务(AWS)， c++， Objective-C，后端，移动，Swift, iOS

The most amazing...

...experience in development is getting a project in the hands of real-world users and seeing how your work is improving their life.

Work Experience

iOS和移动技术主管

2021 - PRESENT
Shackle
  • 定义并实现了最初的应用架构和框架.
  • 将iOS团队扩大到三人，并让他们负责项目架构.
  • 在非常紧张的时间内完成了一个POC和一个MVP.
  • Guided back-end and Android teams with respect to mobile API definition and implementation details.
  • Set up remote logging and observability and assisted with finding bugs in third-party hardware remotely.
  • Used and contributed to the back-end and DevSup projects (PostgreSQL, gRPC, Node.js和Google Cloud).
技术:SwiftUI、模型视图视图模型(MVVM)、gRPC、依赖注入, CI/CD Pipelines, Swift, UIKit, Unit Testing, Apple Design, MQTT, TestFlight, App Store

Tech Lead/Architect

2017 - 2019
fashionTrade(自由)
  • Designed and implemented the proof of concept (POC) of fashionTrade's B2B fashion buying and selling app and scaled it up to commercial deployment.
  • Built the development team and grew it up to a four-person team that was in charge of screening and selecting candidates.
  • Defined the API, 指导API的后端开发, 并在BE团队时间有限的时候构建较小的后端部分.
  • Assisted the PM in defining the product and was actively contributing features and UX.
  • 为测试和生产构建了应用程序的自动部署工具, 哪些被用作CI管道的基础.
技术:Xcode，后端，算法，敏捷，移动，持续集成, Cloud Computing, REST, iOS, Swift, APIs, UIKit, 模型视图视图模型(MVVM), Unit Testing, UI Testing, REST APIs, WebSockets, Apple Design, TestFlight, App Store

高级移动工程师导航应用

2009 - 2017
TomTom (freelance)
  • Improved the iPhone-specific UX and the C++ integration; guided and trained the development team to improve their skills in these fields.
  • Did the heavy-lifting for supporting iOS in TomTom's C++ platform; ported all the software to 64 bit when Apple started mandating this.
  • 处理在该领域发现的最复杂的问题.g., when iOS introduced a bug that caused the app to crash after a few hours of use.
  • 修复了受java启发的基本应用程序架构, 这对于iOS来说不是最佳选择, 节省了团队花费在“逆规律工作”上的大量时间."
  • 引入了对从右到左的支持(i.e.(阿拉伯语)脚本在应用程序.
  • Contributed to CI, distribution, and other tooling required to maintain and deploy the app.
  • Contributed to hiring and screening candidates, interviewing and appraising CVs.
  • 为产品管理和产品定义小组做出贡献.
  • 担任苹果开发人员支持的技术联络点.
Technologies: 后端，敏捷，iOS, Objective-C，移动，objective - c++， c++， UIKit, Unit Testing, UI Testing, REST APIs, Apple Design, TestFlight, App Store

移动主管和架构师

2011 - 2013
TomTom出租车(自由职业者)
  • Kick-started the mobile app development for TomTom Taxi; took on lead and architect roles until commercial release.
  • Worked with the PM to define functionality and UX; implemented initial versions.
  • 实现了在Android上运行的Taxi应用程序的POC.
  • 指导后端团队设计和实现REST API.
技术:Xcode, Back-end, Agile, Mobile, REST, iOS, Objective-C, APIs, UIKit, Unit Testing, REST APIs, Apple Design, TestFlight, App Store

Team Lead, iOS

2009 - 2009
Ahold (freelance)
  • Served as the team lead and architect for the initial launch of the signature app of the Netherlands' largest retailer.
  • 帮助定义产品的功能和用户体验.
  • 从移动角度定义客户机-服务器API.
  • 帮助建立和扩大团队(最多5名开发人员), screening, interviewing, team organization).
  • Contributed to securing the app and the API (passing the external audit on the first attempt).
技术:Xcode, Agile, Mobile, Security, REST, Objective-C, iOS, APIs, UIKit, Unit Testing, REST APIs, App Store

架构师，团队领导

2005 - 2009
ImBeeld / Cammit(自由)
  • Helped the MT to decide between build or buy of a security camera management solution and started the building phase.
  • Grew the tech team (+4 people) and trained the team to learn key skills for the project.
  • Built and implemented the entire service offering (front end, back end, and mobile).
  • 与第三方组件集成(摄像头API、短信网关和ERP).
  • 架构和构建流管道, 从摄像机接收并将流多路复用到几个客户端.
  • 设计并搭建分布式视频存储./检索/管理栈.
  • Researched and built an image processing pipeline for motion detection to trigger alarm events for our users.
技术:Xcode, Back-end, Algorithms, C++, Perl, 后端性能, iOS, Objective-C, Mobile, PostgreSQL, Full-stack, Security, Video Streaming, REST APIs

Kernel Developer

2004 - 2004
TomTom (freelance)
  • Worked on drivers (USB) and kernel (suspend and resume) for the custom hardware of TomTom's first portable navigation device during its RTM and go-to-market phase.
技术:Windows内核驱动，Linux，内核，C, c++

Development Manager

1999 - 2002
Launchalot
  • Managed the 16 person engineering team that developed licensable cross-platform (Linux, macOS, 和Windows) c++框架，用于丰富的多媒体渲染和复杂的ui, 以及基于这些框架的定制解决方案.
  • Oversaw the development of the completely automated playout solution for the country's best-ranking FM radio station.
  • Maintained the frameworks and radio applications and expanded on them to add digital streaming over the public internet and DVB for broadcast networks (freelance).
  • 创建了一个自动播放广播音乐电视的应用程序, based on QuickTime for video decompression plus rendering to the (Blackmagic) broadcast video hardware, and CoreImage for configurable transitions between clips and adverts (freelance).
  • 管理开发人员支持和文档团队.
技术:算法, Objective-C, Performance, Image Processing, Streaming, DVB-S, MPEG, 用户界面(UI), C++

汤姆汤姆导航应用程序

http://www.tomtom.com/en_gb/sat-nav/sat-nav-app/go-mobile/
TomTom's satnav app for iOS was the first turn-by-turn navigation app in the App Store and was wildly successful in its first few years. 我开发了两个版本的应用, 它们在很大程度上是相互独立的, 在几年的时间里. 作为一个更大的团队的一员，我贡献了应用程序的关键部分. I trained and guided team members in some complex areas where knowledge was lacking in the company's existing teams.

绿地移动大型B2B批发项目

The platform offered (amongst much more) a trading solution for fashion wholesale buyers and sellers. I was asked to build the MVP of the mobile app and afterward to scale the project and the team for production. The app was accounted for the bigger part of the company's turnover immediately when it became available. We fine-tuned the UX for maximum productivity on the limited screen sizes and network inherent in mobile.

Taxi Rider App

I bootstrapped mobile apps (iOS and Android) for a service that linked customers with taxi drivers. The app interfaced with a back-end and an on-dash device in the taxi to support the entire customer journey, 从选择目的地和接机点到选择司机, payments, route calculation, 以及时间和成本估算.

我设计并实现了应用程序的初始版本, 扩展了移动开发团队, 我们一起成功地将应用程序投放到app Store. I took part in the APIs and back-end design architecture and supported the UX designers to use the correct mobile-specific design patterns.

Languages

Swift, Objective-C, C, c++， Perl, SQL, Java, JavaScript, TypeScript

Frameworks

UIKit, AppKit, Combine, SwiftUI, gRPC

Libraries/APIs

核心图形，REST api，核心动画，OpenGL, OpenGL ES

Tools

Xcode, Auto Layout, TestFlight, Git, GitHub, MQTT, Shell, Jira, Subversion (SVN)

Platforms

iOS, Mobile, Kernel, Android, Amazon Web Services (AWS), Docker, MacOS, Unix, Linux, Firebase

Other

Objective-C++, 用户界面(UI), Debugging, Greenfield, Optimization, 性能分析, Performance Tuning, Apple Design, App Store, Security, Image Processing, Streaming, Performance, 客户机-服务器模型, Scripting, Videos, Concurrency, 并行计算, Multithreading, Video Streaming, Audio Streaming, 后端性能, TCP/IP, Network Protocols, Scalability, Systems, 版本控制系统, Distributed Systems, 分布式软件, Algorithms, APIs, WebSockets, Web Servers, Full-stack, Cloud Computing, MPEG, DVB-S, Windows内核驱动程序, Machine Learning, AVFoundation, Back-end, Ajax, TV Broadcasting, Radio, Astrophysics, CI/CD Pipelines, UI Testing

Paradigms

REST, 分布式计算, Agile, Design Patterns, 函数式响应式编程, Unit Testing, DevOps, 持续集成(CI), VIPER Architecture, 函数式编程, 模型视图视图模型(MVVM), 依赖注入

Storage

数据库，PostgreSQL, JSON

1990 - 1997

天体物理学硕士学位

阿姆斯特丹大学-阿姆斯特丹，荷兰

有效的合作

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