Olaf is available for hire

Olaf Kloecker

Verified Expert in Engineering

Full-stack Developer

Location

Edinburgh, United Kingdom

Toptal Member Since

April 1, 2016

Olaf is a full-stack Java developer who has come a long way since writing his first programs with Turbo Pascal on a handed-down home-built CP/M 80 system. 他是GIAC认证的java安全软件程序员. Olaf likes to write robust, 在高速公路收费系统中商业运行的安全软件, navigation devices, 安全管理平台. 他的一个特殊兴趣是语言处理.

Debugging Back-end Full-stack Development Web Development Full-stack MERN Stack Java REST APIs JavaScript Vanilla JS React Express.js CSS Leaflet Redux iBATIS Jitsi

Portfolio

WeatherWorks

Bootstrap, CSS3，后端，Git, Linux, Web开发，Redux, REST api...

Gepalon Networks Ltd (via Toptal)

React, Node.. js, MongoDB, PostgreSQL, Jitsi，前端，HTML5, React Redux, CSS...

Brightpunch, Ltd. (via Toptal)

Jitsi, CSS3, CSS, HTML5，后端，Git, Linux, Node.js, Web Development, Redux...

Experience

Linux - 20 years Java - 18 years Code Review - 15 years JavaScript - 9 years React - 8 years Web Development - 6 years Full-stack - 6 years Node.js - 3 years

Availability

Part-time

Preferred Environment

Bash, Vim文本编辑器，IntelliJ IDEA, Windows, Linux

The most amazing...

...thing I've researched and coded is a grapheme-to-phoneme converter using an artificial neural net.

Work Experience

自由职业高级全栈开发人员

2017 - PRESENT

WeatherWorks

架构硬件和软件基础设施和技术.
Transformed a given design into a fully functional single-page REST-backed web application.
实现了前端的所有部分, including maps, 使用React和相关库, including different roles, user, admin, 以及外部开发者仪表板.
写了基础设施的绿皮书. 为外部开发人员开放API，提高性能和安全性.
搭建AWS Linux服务器并部署后端, front end, and dependencies, including NGINX and firewalls.
Engaged in problem analysis on the front end, back end, a MongoDB database, and servers.
Extended the Node.js back end with new functionality, improved the codebase, and fixed memory leaks.
通过引入微服务提高了效率, parallelization of operations, and Redis in-memory data caching.
不断将依赖项更新到最新版本.
将代码库转换为使用ES6 Promises而不是回调. Refactored code into TypeScript to integrate into the wider company software landscape.

Technologies: Bootstrap, CSS3，后端，Git, Linux, Web开发，Redux, REST api, Full-stack, CSS, HTML5, Loopback, Node.js, Socket.IO, JavaScript, Redux-Saga, React, Redis, APIs, MongoDB, MongoDB Atlas, ES6 Promises, Front-end, React Redux, Express.js, Bash，调试，REST, Bash Script, Bug分析 & Reporting, MERN Stack, TypeScript, Axios, Vanilla JS, Jest, Leaflet, Maps, Databases, Full-stack Development, API Integration

医疗流媒体和分析应用程序的前端开发者

2020 - 2021

Gepalon Networks Ltd (via Toptal)

Extended the Jitsi Meet platform to integrate artificial intelligence (neural network) generated image inference to highlight body tissue parts in a live video stream.
Configured and integrated Prosody modules of Jitsi Meet platform to allow token-based video conference sessions and record join end times.
Created Node.js and Express-based back end to store session and user information in PostgreSQL database.
Created user and admin dashboards to handle user meta information in relation to Jitsi Meet sessions.
Created Node.. js后端将TensorFlow推断作为REST服务运行.

Technologies: React, Node.. js, MongoDB, PostgreSQL, Jitsi，前端，HTML5, React Redux, CSS, CSS3, Debugging, REST, ES6 Promises, Tailwind CSS, Express.js, Axios, Vanilla js，数据库，全栈开发，API集成

Senior Front-end Engineer

2020 - 2020

Brightpunch, Ltd. (via Toptal)

Extended the Jitsi Meet video conferencing platform to allow participants to cooperatively draw with their mouse over the moderator's video stream after being granted permission.
添加了包含形状的自定义工具栏, color, line width choosers, and undo, redo, 并清除会话控制按钮.
利用使用自定义消息格式的内部消息传递功能.
创建一个CSS/ javascript线宽选择器，与颜色选择器一起使用.

技术:Jitsi, CSS3, CSS, HTML5，后端，Git, Linux, Node.js, Web Development, Redux, REST APIs, Full-stack, HTML5 Canvas, JavaScript, React, Front-end, React Redux, Debugging, ES6 Promises, Tailwind CSS, Express.js, Axios, Vanilla js，数据库，全栈开发，API集成

Web Developer

2017 - 2017

Pixelrein

在桌面网站的基础上为移动设备创建了一个响应式网页.

Technologies: CSS, HTML5, Back-end, Git, Linux, React, Web Development, Redux, Full-stack, JavaScript, CSS3, Jinja, REST APIs, Front-end, React Redux, REST, Redux Thunk, ES6 Promises, Axios, Vanilla JS, Databases

自由高级Java开发人员|自由顾问

2016 - 2017

TradeReplay (via Toptal)

Consulted with clients on which technologies to use, cloud platforms, and payment providers.
创建硬件和软件架构, data model, and overview diagrams for the web-based self-service members' area of a standalone desktop app to provide functionalities for registration, profile change, 订阅更改以及管理区域.
Developed the members' area based on Play Java with Twirl templates and Ebean ORM to PostgreSQL database.
Installed a system and documented the setup on a Linux server—integrating WordPress for a third-party-provided public promotional website.
定期与客户沟通, mainly through Asana, 但也通过电子邮件和电话提供每周进度报告.

Technologies: Back-end, Play, Git, Web Development, REST APIs, Full-stack, NGINX, Linux, PostgreSQL, Bootstrap, Java, Play Framework, Front-end, REST, Databases, Full-stack Development, API Integration

自由建筑师|自由开发者

2016 - 2017

Freelance Work

设计并独自开发了Trunksta.De是一个社交分享平台，可以在别人的车里发送物品.
使用React/Redux将前端开发为单页应用程序.
Implemented the back end with the Lightbend Play Java framework with an Nginx reverse proxy/load balancer and PostgreSQL database mapped to Java entities through Ebean-ORM.
指定基础架构需求，并在Linux服务器上安装系统.

Technologies: Back-end, Git, Java, Play Framework, PostgreSQL, React, Databases, Full-stack Development

Service Consultant

2015 - 2015

Cellent AG (Fellbach, Germany)

Provided second- and third-level support for a complex legacy web-based project-management system in the automotive industry spanning a variety of frameworks and technologies.
作为一个主要部件的主要客户联系人.
Coordinated incident support, maintained systems, performed analysis, and fixed bugs.
分析来自客户端的错误报告并修复错误.
通过手动SQL命令管理数据库数据和结构.

Technologies: Back-end, Confluence, Jira, Apache Struts, Jakarta EE, Java, Code Review, Databases

Software Development Engineer

2013 - 2014

Dell Inc./Dell SecureWorks (Edinburgh, UK)

Extended and maintained complex, robust, and secure business-critical software systems for managed security services and counter-threat units.
Fixed bugs in a legacy Perl application for manual and automatic device maintenance.
对新建系统的所有部分进行文档化.
参加每日的scrum会议.
对新开发的功能进行用户验收测试.
获得GIAC安全软件程序员- java (GSSP-Java)认证.
Cloudera Apache Hadoop认证开发者(CCDH).

Technologies: Back-end, Scrum, Full-stack, OpenGrok, iBATIS, MyBatis, Confluence, Jira, FindBugs, Apache Tomcat, Ext JS, Apache Maven, Perl, Bash, Linux, Java, Code Review, Bash Script, Databases

Software Engineer

2006 - 2013

TomTom软件有限公司(英国爱丁堡)

Supported the maintenance and improvement of the in-house continuous integration system for automated tests.
Created a tool to visualize a large number of trip logs into global and regional traffic heat maps.
通过WebKit测试，支持一个导航设备平台的开发, automatic route testing, and embedded testing/debugging.
Created sample Android apps for current navigation devices to be included in an API toolkit for third parties extending the platform (e.g., Renault R-Link).
开发了一个SVN/Maven存储库爬虫来检查项目运行状况, inconsistencies, missing information, prevent bit rot, ensure buildability, detect dependency cycles, 并确定逻辑构建序列.
Created a RESTful web back end for a prototype device to store/retrieve data; implemented automatic tests.
将WebDAV服务器从c++移植到Java.

Technologies: Back-end, JavaScript, Ajax, Apache HTTP Server, HTML, Jenkins, Apache Maven, Android, Bash, Linux, Java, Code Review, Bash Script, TestNG, Maps, Databases

Professional Systems Engineer

2001 - 2005

T-Systems GEI GmbH(德国波恩)

Developed a GIS application to convert a detailed digital street map into an abstract motorway graph, processing highly-complex temporally-changing data structures with graph algorithms.
创建了一个GUI程序为GIS可视化道路地图.
Built a back end of a web booking system for toll tickets including PDF creation.
支持新成员和初级团队成员熟悉软件.
Introduced static metrics (metrics, code coverage, dependency analyses) into the build lifecycle.
为GUI应用程序编写最终用户文档.

Technologies: Back-end, AWT, Swing, PDF, XML, HTML, UML, CSV, Ant Design, JUnit, JDBC, SQL, Java, Code Review, Maps, Databases

Unix/Linux Systems Administrator

1998 - 2001

Tops.net GmbH & Co. KG (Bonn, Germany)

支持并扩展了SoHo公司基于linux的internet拨号服务器.
Created the back end of a document management system converting SGML documents into PDF files via LaTeX.
管理客户端服务器和网络.
设置和安装linux服务器.

技术:LaTeX, Perl, Bash, Unix, Linux, Bash Script

Experience

Memo Molecule

http://memomolecule.com

I developed a responsive web app to create email reminders with powerful recurrence rules like "every last working day of the month" or "every third Saturday,“考虑到当地时区.

它是在前端使用React和Node构建的.js (Loopback/Express.. js)在后端使用MongoDB数据库. 它还使用语义UI进行样式设计，并内置了多语言支持.

WeatherWorks Advantage

http://weatherworksadvantage.com/

I built a forecast management system for winter and non-winter events comprising a complex React user and admin dashboards, report pickup pages and a Node.. js后端由MongoDB数据库支持.

TRUNKSTA.DE | Social Sharing Platform

http://trunksta.de

Sole (software and infrastructure) architect and full-stack developer of a social sharing platform (no design) for the German market. Built with React.前端使用Java Play/PostgreSQL/Nginx. 它包括平台的所有方面，包括用户身份验证, management, admin functions, transaction email, PayPal integration, and business logic. 我非常依赖Play的反应性功能, 和Java 8结构(集合流), Optionals, and Lambdas).

Launched in December 2016.

Gaelphon

http://gaelphon.gaelictools.com

I developed a data-driven, artificial neural network-based grapheme-to-phoneme converter for Scottish Gaelic (not yet available online).

Faclair Dictionaries and Grammar

http://gaelictools.wordpress.com/

These are Scottish Gaelic/English/German dictionaries and a concise grammar text for the Scottish Gaelic language, available as Kindle e-books.

Skills

Languages

JavaScript, Java, HTML, HTML5, CSS, Bash Script, XML, UML, CSS3, Bash, SQL, Perl, TypeScript

Frameworks

Redux, Express.js, Vanilla JS, Loopback, React Native, Play, TestNG, JUnit, Tailwind CSS, Ant Design, Apache Struts, Play Framework, Bootstrap, Jinja, Ext JS, Swing, Hadoop, iBATIS, Jest

Libraries/APIs

REST api, Redux-Saga, React, Node.js, JSON API, React Redux，传单，Ebean ORM, AWT, HTML5 Canvas, Socket.IO, Java安全，SLF4J, MyBatis, JDBC

Tools

Redux Thunk, Confluence, Jira, LaTeX, Git, IntelliJ IDEA, Subversion (SVN), Eclipse IDE, Vim Text Editor, Apache HTTP Server, Apache Tomcat, NGINX, Jenkins, Sonar, Mercurial, Perforce, Apache Ant, Apache Maven, MongoDB Atlas, AWS IAM

Paradigms

REST、敏捷软件开发、面向对象设计(OOD)、Scrum

Storage

JSON, MySQL, MongoDB, PostgreSQL, Databases, Redis, Amazon DynamoDB, Amazon S3 (AWS S3)

Other

Debugging, Bug Analysis & Reporting, Web Development, Full-stack, Front-end, Front-end Development, Back-end, APIs, MERN Stack, Axios, Maps, Full-stack Development, API Integration, Germany, Code Review, Semantic UI, CSV, PDF, OpenGrok, Ajax, FindBugs, GUI Development, TCP/IP, Jitsi, ES6 Promises, Amazon API Gateway

Platforms

Kindle, Linux, Windows, Unix, Jakarta EE, Google App Engine, Java EE, Android, Amazon Web Services (AWS), AWS Cloud Computing Services, Amazon EC2, AWS Lambda

Education

1993 - 2001

语音学硕士学位, Speech Signal Processing, Computational Linguistics, Computer Science, and Celtic Languages

波恩大学-德国波恩

Certifications

MARCH 2024 - MARCH 2027

AWS认证开发人员-助理

亚马逊网络服务培训和认证

MAY 2014 - MAY 2018

GIAC安全软件程序员-Java, GSSP-Java

giac.org

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