Mohamed is available for hire

Mohamed Khaled

Verified Expert in Engineering

Back-end Developer

Alexandria, Alexandria Governorate, Egypt

Toptal member since January 3, 2022

Expertise

Back-end Developers Algorithms API Full-stack Integration Web Development AWS RDS REST API Database Postman

Bio

Mohamed is a back-end engineer who specializes in the design and development of complex architecture and infrastructure. He led a team to deliver a B2B2C shipping system with a customized shipment-flow engine, built a smart in-door navigation service based on NFC-tag [NFC technology], and transferred UI/UX designs to a fully-featured mobile app for iOS and Android devices. Mohamed is proficient with integrations, CMS, and authentication strategies.

Portfolio

AAA Club Alliance

Storybook, Figma, Vercel, Sitecore, Headless Software, Migration...

OneConnxt LLC

Node.js, Express.js, React, PostgreSQL, APIs, JSON, FFmpeg, Streaming, GitHub...

Puttshack

Node.js, Apache Kafka, PostgreSQL, REST, REST APIs, APIs, Integration...

Experience

Algorithms - 6 years
Node.js - 4 years
NestJS - 4 years
MongoDB - 3 years
PostgreSQL - 2 years
React - 2 years
Microservices Architecture - 1 year
React Native - 1 year

Availability

Full-time

Preferred Environment

Windows Subsystem for Linux (WSL), Windows, Linux, Visual Studio Code (VS Code), Postman

The most amazing...

...cross-platform application I've designed was a ''supermarket in your pocket'' for bakeries, groceries, fruits, vegetables, and household products.

Work Experience

Lead Development Engineer

2023 - PRESENT

AAA Club Alliance

Led the creation of the solution's gateway using GraphQL Mesh, which serves as the future gateway for the company's digital products, enabling seamless consumption of multiple sources, including REST APIs, SOAP, and GraphQL.
Led the integration of Adobe Experience Platform using various products such as Adobe Launch, Adobe Target, Adobe Analytics, and Sitecore Customer Data Platform.
Utilized collected data for subsequent analysis and implementation of targeted marketing campaigns, ensuring optimal utilization of insights for business growth and customer engagement.
Spearheaded the development of a new design system for the company, including the creation of a Storybook for component management and documentation.
Participated in meetings with technical teams and architects from industry-leading companies such as Adobe, Vercel, and Sitecore, fostering collaboration and aligning strategies for project success.
Collaborated with fellow leaders in the transformation from the legacy system to a Sitecore Headless Solution, allowing the content editors to rapidly create new pages using already developed react reusable components.

Technologies: Storybook, Figma, Vercel, Sitecore, Headless Software, Migration, Adobe Experience Cloud, Adobe Analytics, Adobe Target, Adobe Launch, Turbo, GraphQL, Mesh Development, SDKs, Integration, API Integration, REST, REST APIs, SOAP, Architecture, Web Architecture, Web Application Architecture, Reusable Libraries, Data Collection, Tags, Booking Systems, Single-page Checkout, Checkout, Next.js, Leadership, GitHub, React, Front-end Development, API Design, API/Services Architecture, CI/CD Pipelines, Software Engineering, Tailwind CSS, Front-end, Third-party Integration, System Design, API Architecture, Full-stack, Data Aggregation, Minimum Viable Product (MVP), Responsiveness, Caching, Radix UI, Zustand, RESTFul APIs

Full-stack Developer

2023 - 2023

OneConnxt LLC

Contributed to video stream processing and manipulation using FFmpeg, with experience in transcoding/encoding MPEG-TS streams to MP4 format for various multimedia applications.
Worked with video codecs such as H.264 (AVC) and audio codecs like AAC and libfdk_aac, leveraging industry-standard formats for efficient multimedia content delivery and playback.
Managed file systems and automated directory creation, enhancing efficiency in video content management workflows.
Maintained the admin panel and the server and added more features such as real-time notifications triggered by videos entering new stages (starting, started, streaming, live, transcoding, encoding, success, failure).

Technologies: Node.js, Express.js, React, PostgreSQL, APIs, JSON, FFmpeg, Streaming, GitHub, Video Processing, Front-end Development, API Design, API/Services Architecture, CI/CD Pipelines, Software Engineering, Front-end, System Design, Full-stack, RESTFul APIs

Senior Software Engineer

2022 - 2023

Puttshack

Participated in meetings with key stakeholders, including the CTO, game system architect, CMOs, and data engineers. Collaborated on the formulation of targeted marketing campaigns.
Spearheaded the development and maintenance of the Puttshack reservation system. Integrated with 3rd-party services such as Punchh (loyalty system), GiftPro, Focus (gift cards system), Sevenrooms (guest experience system), and Tripleseat (event system).
Developed Kafka listeners and publishers for efficient communication with the game system, enabling real-time updates to the web and seamless event handling for guests and reservation updates.
Developed data transformers and mappers for a better separation of concerns between the domain and the infrastructure. Utilized NestJS microservices transport abstraction layer to modularize the application and ensure the future scalability plan.

Technologies: Node.js, Apache Kafka, PostgreSQL, REST, REST APIs, APIs, Integration, API Integration, Toast (Point-of-sale Platform), Punchh, Stripe, Stripe API, Tripleseat, Booking Systems, Amazon RDS, Amazon Web Services (AWS), Focus Pos, GiftPro, SevenRooms, NestJS, Single-page Checkout, Checkout, Next.js, Migration, Web Application Architecture, Reusable Libraries, Tags, Leadership, Scalable Architecture, GitHub, API Design, API/Services Architecture, CI/CD Pipelines, Redis, Sentry, Software Engineering, Third-party Integration, System Design, API Architecture, Startups, Full-stack, Data Aggregation, Minimum Viable Product (MVP), Responsiveness, Caching, RESTFul APIs, CQRS, Domain-driven Design (DDD), Jest

Senior Software Engineer

2022 - 2022

Mothership,

Owned the accounting service that manages B2B financial transactions and worked closely with the CTO to plan and design the company's vision for the following quarters.
Built a complete reusable framework that embraces feature-driven development (FDD), command-query separation (CQS), and separation of concerns.
Developed a complete business validation layer that throws custom business exceptions with custom status codes.
Created a Unit of Work design pattern to manage and control database transactions and separated the domain layer from the persistence layer using mappers.
Participated in the customer platform team, attended daily meetings, and managed new accounting requests through the Asana board and tickets.
Wrote heavy and complete unit tests for different components. Followed the company's code standards and formatting using prettier rules.

Technologies: TypeScript, JavaScript, TypeORM, Express.js, Architecture, Domain-driven Design (DDD), Feature-driven Development (FDD), REST APIs, API Integration, Microservices, Separation of Concerns (SoC), Jest, Back-end, Unit Testing, REST, Modular Design, RESTful Microservices, Databases, Docker, Amazon Web Services (AWS), Ubuntu, Apache Kafka, Kubernetes, Scalable Architecture, Scalable Application, GitHub, Git, Software Architecture, Scalability, JSON Web Tokens (JWT), Middleware, Message Queues, Integration, Web Development, eCommerce, JSON, Test-driven Development (TDD), Refactoring, API Development, RDBMS, Amazon RDS, Amazon Simple Queue Service (SQS), Parsers, Single-page Checkout, Migration, Reusable Libraries, API Design, API/Services Architecture, CI/CD Pipelines, Redis, Sentry, Software Engineering, System Design, API Architecture, Data Aggregation, Minimum Viable Product (MVP), NestJS, RESTFul APIs, CQRS

Senior Back-end Engineer

2022 - 2022

Hello Iteration,

Used the NestJS microservices transport abstraction layer to modularize the application and grant the future scalability plan. Wrote a custom NestJS transport layer for Azure Service Bus to enable publishing and to listen to events.
Wrote an abstraction and a skeleton for a video-on-demand service composed of smaller microservices.
Designed and developed an importer microservices that imports data from different data sources.
Outlined and built a receiver microservice that indexes data, eliminates redundancy, and stores data in Azure Blob Storage.
Conceived and developed a processor microservice that processes new data and stores updates using an event sourcing technique and creating a snapshot for a fast replay.

Technologies: NestJS, Architecture, Event Sourcing, APIs, Azure, Amazon S3 (AWS S3), Azure Blob Storage API, Azure Service Bus, Microservices, Microservices Architecture, MongoDB, NoSQL, REST APIs, Back-end, Unit Testing, Jest, REST, Modular Design, RESTful Microservices, Databases, IT, Cloud Architecture, Docker, Ubuntu, Apache Kafka, Kubernetes, Scalable Architecture, Scalable Application, ETL, ETL Implementation & Design, GitHub, Git, Software Architecture, Scalability, JSON Web Tokens (JWT), Middleware, Message Queues, Integration, Web Development, JSON, API Development, Parsers, API Design, API/Services Architecture, Software Engineering, Third-party Integration, System Design, Startups, Data Aggregation, Caching, RESTFul APIs, CQRS, Domain-driven Design (DDD)

Back-end Engineer

2022 - 2022

Descriptive,

Developed a discount module for gift card scenarios, including lookup, redeem, and void options.
Built a loyalty module, including the integration with Punchh, a third-party loyalty system for managing user rewards and offers.
Used the NestJS microservices transport abstraction layer to modularise the application, granting the future scalability plan.
Maintained and fixed reported bugs and issues in an Agile environment.

Technologies: Node.js, Modular Design, Architecture, APIs, TypeScript, NestJS, Back-end, Unit Testing, Jest, TypeORM, REST, RESTful Microservices, Microservices, Databases, IT, Cloud Architecture, Docker, Amazon Web Services (AWS), Ubuntu, Apache Kafka, Kubernetes, Big Data, Leadership, Scalable Architecture, Scalable Application, ETL, ETL Implementation & Design, GitHub, Git, Software Architecture, Scalability, JSON Web Tokens (JWT), Middleware, Message Queues, Authentication, Integration, Web Development, eCommerce, CSS, JSON, Test-driven Development (TDD), Refactoring, API Development, RDBMS, Full-stack Development, Amazon RDS, Parsers, Stripe, Single-page Checkout, Web Application Architecture, Reusable Libraries, Tags, API Design, API/Services Architecture, CI/CD Pipelines, Redis, Sentry, Software Engineering, Third-party Integration, System Design, API Architecture, Startups, Full-stack, Data Aggregation, Minimum Viable Product (MVP), Responsiveness, Caching, RESTFul APIs, CQRS

Software Engineer

2021 - 2022

Blackstoneeit

Implemented and developed, in collaboration with the senior architect, a new architecture framework that uses the latest technologies and concepts from DDD, CQRS, and ES (event sourcing).
Implemented ESLint custom rules to encourage developers to follow the code standards.
Wrote MongoDB aggregates and created views to optimize data fetching and overcome (n + 1) query problems.
Implemented and developed a Jira-service desk integration middleware microservice to handle customer requests.
Created a document analyzer micro-service to extract data from PDF documents based on the client's needs to automate uploading the files and extracting the data manually.
Maintained and developed different microservices based on new feature requests or reported bugs.

Technologies: Node.js, TypeScript, Loopback, Microservices, RabbitMQ, Kanban, MongoDB, Jira, Jira REST API, Socket.IO, Domain-driven Design (DDD), ESLint, JavaScript 6, RESTful Services, APIs, REST APIs, ServiceDesk, Infrastructure, API Integration, Architecture, Web Architecture, Back-end Architecture, Back-end Development, Microservices Architecture, RESTful Microservices, NoSQL, WebSockets, Back-end, Unit Testing, Jest, TypeORM, REST, Modular Design, Databases, IT, Ubuntu, Apache Kafka, Big Data, Leadership, Scalable Architecture, Scalable Application, ETL, ETL Implementation & Design, Software Architecture, Scalability, JSON Web Tokens (JWT), Middleware, Message Queues, Authentication, Integration, Web Development, JSON, Test-driven Development (TDD), Refactoring, API Development, Full-stack Development, Bitbucket, Parsers, Checkout, Migration, SDKs, Web Application Architecture, Reusable Libraries, API Design, API/Services Architecture, CI/CD Pipelines, Redis, Software Engineering, Third-party Integration, System Design, API Architecture, Data Aggregation, Minimum Viable Product (MVP), Caching, RESTFul APIs, CQRS

Full-stack Mobile Developer

2020 - 2021

Arabi Market

Implemented and developed RESTful APIs for the mobile app and the CMS.
Integrated third-parties such as payment gateways (Stripe and PayPal), Google Maps (Places), and AWS SNS for sending SMS notifications.
Transferred the UI/UX design to a fully featured mobile app using the Expo framework for both iOS and Android devices.

Technologies: React Native, Node.js, Express.js, Sequelize, PayPal API, Stripe API, Google Maps API, Expo.io, Google Places API, MySQL, Amazon Simple Notification Service (SNS), JavaScript 6, RESTful Services, APIs, HTML, SQL, REST APIs, Infrastructure, API Integration, Architecture, Web Architecture, Back-end Architecture, Back-end Development, Entity–Boundary–Interactor (EBI), React, PostgreSQL, Back-end, REST, Modular Design, Databases, IT, Cloud Architecture, Amazon Web Services (AWS), Full-stack, Ubuntu, Leadership, Scalable Application, GitHub, Git, Software Architecture, JSON Web Tokens (JWT), Authentication, Integration, Web Development, eCommerce, CSS, Progressive Web Applications (PWAs), JSON, Refactoring, API Development, RDBMS, Full-stack Development, Amazon Simple Queue Service (SQS), iOS, Mobile, Android, Stripe, Single-page Checkout, Checkout, Web Application Architecture, Front-end Development, API Design, Software Engineering, Front-end, Expo, Third-party Integration, System Design, API Architecture, Startups, Minimum Viable Product (MVP), Responsiveness, NestJS, RESTFul APIs

Software Engineer

2019 - 2021

Alexapps

Led a team of developers to build and deliver a B2B shipping system with a customized shipment-flow engine with custom states and transitions to track the shipment status.
Built a smart in-door navigation service based on NFC-tag (NFC technology) to find the shortest path to the required destination.
Created cross-platform desktop applications using the Electron framework.
Maintained and fixed bugs and issues for different web apps.
Developed a customizable and reusable administrative panel and front-end components that saved time.

Technologies: Node.js, TypeScript, Sequelize, Mongoose, MySQL, MongoDB, SQLite, Electron, JavaScript 6, RESTful Services, APIs, Vuex, HTML, Vuetify, NestJS, SQL, REST APIs, Infrastructure, API Integration, Architecture, Web Architecture, Back-end Architecture, Back-end Development, Entity–Boundary–Interactor (EBI), Vue, PostgreSQL, NoSQL, Back-end, TypeORM, REST, Modular Design, Databases, IT, Cloud Architecture, Full-stack, Ubuntu, Leadership, Scalable Architecture, Git, JSON Web Tokens (JWT), Middleware, Authentication, Integration, Web Development, eCommerce, CSS, Progressive Web Applications (PWAs), JSON, Test-driven Development (TDD), Refactoring, API Development, RDBMS, Full-stack Development, Bitbucket, Booking Systems, Single-page Checkout, Checkout, Web Application Architecture, Front-end Development, API Design, Software Engineering, Front-end, Third-party Integration, System Design, API Architecture, B2C, Startups, Minimum Viable Product (MVP), RESTFul APIs

Back-end Developer

2018 - 2019

Q e-markets

Developed new features in an agile team and maintained and fixed reported bugs and issues.
Added a new authentication strategy using Google OAuth 2.0 APIs.
Ensured authorization of resolvers by creating policies and permissions and parsing GraphQL nodes based on request permissions.

Technologies: Node.js, TypeScript, Express.js, GraphQL, MySQL, Sequelize, JavaScript 6, RESTful Services, APIs, SQL, REST APIs, API Integration, Architecture, Web Architecture, Back-end Architecture, Back-end Development, PostgreSQL, Back-end, REST, Modular Design, Databases, Full-stack, Ubuntu, JSON Web Tokens (JWT), Middleware, Web Development, eCommerce, JSON, API Development, RDBMS, Web Application Architecture, API Design, Software Engineering, API Architecture, Startups, RESTFul APIs

Experience

TDRA Management Services

https://tdra.gov.ae/

TDRA ensures excellent telecommunication services by implementing relevant policy and regulatory frameworks, developing human resources, and promoting research and development. As a software engineer at TDRA, I designed, implemented, and developed different services and management systems. I also developed highly effective frameworks that focus on the separation of domain development and infrastructure concerns.

Puttshack

https://www.puttshack.com/

A Nest.js-based booking application for mini-golf games. As a back-end engineer, I was responsible for creating modules and integrating third-party gift card provider's APIs such as FocusPOS and UK GiftPro APIs. I also Integrated a loyalty system such Punchh for managing user's rewards and offers.

Waselleeom Shipping system

http://waselleeom.com/

A B2B shipping system that accepts shipping orders from different vendors to be delivered to customers with a tracking system. As a team leader, I lead a team of two back-end engineers and two front-end engineers in designing and developing the company’s features.

Arabi Market

A cross-platform app designed with a mindset of "a supermarket in your pocket" for bakeries, groceries, fruits, vegetables, and household products. I was a full-stack developer who designed and developed RESTful APIs for both the app, the CMS, and the mobile app using the latest framework, Facebook's Expo.io, ensuring smooth customer interactions.

Education

2015 - 2020

Bachelor's Degree in Computer Science

Helwan University - Helwan, Cairo, Egypt

Skills

Libraries/APIs

Node.js, React, REST APIs, API Development, Jira REST API, Socket.IO, PayPal API, Stripe API, Google Maps API, Google Places API, Vue, Vuex, Stripe, Azure Blob Storage API, FFmpeg

Tools

Postman, Sequelize, Expo.io, Mongoose, GitHub, Git, Bitbucket, Jira, ServiceDesk, Amazon Simple Queue Service (SQS), SevenRooms, Turbo, Sentry, Expo, RabbitMQ, Amazon Simple Notification Service (SNS), Figma, Adobe Analytics, Adobe Target

Languages

TypeScript, JavaScript, JavaScript 6, GraphQL, SQL, HTML, CSS

Frameworks

Loopback, Express.js, NestJS, Vuetify, JSON Web Tokens (JWT), Next.js, React Native, Electron, Jest, Tailwind CSS

Paradigms

Microservices, Web Architecture, Back-end Architecture, Modular Design, Scalable Application, Refactoring, Web Application Architecture, API/Services Architecture, API Architecture, CQRS, Unit Testing, ETL, ETL Implementation & Design, Test-driven Development (TDD), Microservices Architecture, Kanban, REST, Event Sourcing, B2C

Platforms

Visual Studio Code (VS Code), Vercel, Linux, Ubuntu, Apache Kafka, iOS, Mobile, Android, Adobe Experience Cloud, Windows, Azure, Docker, Amazon Web Services (AWS), Kubernetes, Toast (Point-of-sale Platform)

Storage

Databases, JSON, MongoDB, PostgreSQL, MySQL, SQLite, NoSQL, RDBMS, Redis, Amazon S3 (AWS S3)

Other

Algorithms, Data Structures, Rich Internet Applications, Domain-driven Design (DDD), RESTful Microservices, API Integration, APIs, RESTful Services, Architecture, Back-end Development, TypeORM, Feature-driven Development (FDD), Back-end, Full-stack, Leadership, Scalable Architecture, Software Architecture, Scalability, Middleware, Authentication, Integration, Web Development, eCommerce, Amazon RDS, Punchh, Booking Systems, Single-page Checkout, Checkout, Headless Software, Adobe Launch, Reusable Libraries, Front-end Development, API Design, Software Engineering, Third-party Integration, System Design, Startups, Data Aggregation, Minimum Viable Product (MVP), Responsiveness, Caching, RESTFul APIs, Windows Subsystem for Linux (WSL), OOP Designs, Distributed Systems, Entity–Boundary–Interactor (EBI), Infrastructure, Message Queues, Full-stack Development, Parsers, Storybook, Sitecore, Migration, Mesh Development, SDKs, Data Collection, Tags, CI/CD Pipelines, Front-end, Radix UI, Zustand, Machine Learning, ESLint, Azure Service Bus, Separation of Concerns (SoC), WebSockets, IT, Cloud Architecture, Big Data, Progressive Web Applications (PWAs), Streaming, Tripleseat, Focus Pos, GiftPro, SOAP, Video Processing

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring