Software engineer

Ahmad
Saleh

Software engineer · architecture · reliability

Four years shipping production systems and APIs — clean architecture, practical performance, and systems that stay dependable under load.

Download CV

01 · Focus

Reliable APIs

Production backends with clear contracts, solid debugging habits, and maintainable architecture.

02

Data & Search

Pipelines, document modeling, and indexing workflows that keep source systems and search aligned.

03

Performance

Query and runtime fixes grounded in real workloads — including large Oracle and Cassandra datasets.

runtime.log

info query.optimize latency 2h → 3s

ok opensearch.index sync=aligned

info deploy.ready env=production_

4+

Years shipping

99.9%

Query win

5+

Major projects

20

Engineer team

▸C / C++▸Java▸Spring Boot▸Oracle▸Cassandra▸OpenSearch▸AWS▸REST APIs▸System Design▸Production Debugging

About

Built for systems that stay up

I'm a software engineer with 4 years at Progineer Technologies — high-performance backends, stability, efficiency, and correctness.

Spring Framework, REST APIs, secure auth. Deep work with Oracle, Cassandra, and MongoDB — modeling, query optimization, and large production datasets. I also debug incidents, read logs, and untangle deployment issues.

Enterprise reality: long-lived codebases, strict requirements, and cross-functional teams. I optimize for reliability and maintainability — not demos.

Education

Bachelor of Computer Science

An-Najah National University

Nablus · 2018 – 2022

Languages

ArabicNative
EnglishFluent

01

Production-first

Reliability over shortcuts — production incidents, runtime debugging, and correctness in long-lived enterprise systems.

02

System engineering

Performance-critical components, bottlenecks, deployments, and how systems behave under real load.

03

Database depth

Oracle schema/SQL optimization and Cassandra modeling across large production datasets.

Skills

Tools I reach for

Core Backend

01

Low-level and language foundations I use when latency and memory actually matter.

CC++JavaMemory ManagementPerformance Optimization

Databases

02
Oracle SQLCassandra NoSQLMongoDBMySQLData ModelingQuery Optimization

Backend Frameworks

03
Spring BootSpring SecurityJPA/HibernateRESTful APIs

Cloud & Infrastructure

04
AWS EC2AWS S3ALBAuto ScalingLaunch TemplatesVPC NetworkingNAT GatewayAWS Secrets ManagerLinuxSystem Architecture

Search & Data

05
Search IndexingIndexing Data GenerationData PipelinesDocument Modeling

DevOps & Tools

06
MavenGitProduction DebuggingLog AnalysisSystem Design
◆memory-safe paths◆index design◆query plans◆incident response◆API contracts◆search documents◆AWS networking◆log forensics

Projects

Selected work

01 · Project

Bloom – Venue Booking Platform

Personal Project
Client
ALB
Spring API
MongoDB
S3

Problem

Venue booking platforms need to handle complex reservation logic (full-day, time-based, event-based), ensure data consistency across concurrent bookings, and provide secure multi-tenant access with role-based permissions.

Solution

Built a production-ready Spring Boot REST API with clean layered architecture, implementing robust booking workflows, JWT authentication with refresh tokens, and database-driven multi-language support. Evolved the deployment into a scalable AWS architecture using ALB, Auto Scaling Groups with Launch Templates, VPC networking (public/private subnets, NAT Gateway), and AWS Secrets Manager for secure configuration.

View on GitHub →

Tech stack

Backend

JavaSpring BootSpring Security

Database

MongoDB

Infrastructure

AWS EC2AWS S3ALBAuto ScalingLaunch Templates

Networking

VPCPublic/Private SubnetsNAT Gateway

Security

AWS Secrets Manager

Integration

FirebaseOpenAI API

Documentation

Swagger/OpenAPI

Role

  • •Architected and implemented the entire backend system using clean architecture principles (Controllers → Services → Repositories)
  • •Designed and implemented JWT-based authentication system with refresh token rotation and role-based access control
  • •Built generic ownership validation framework ensuring users can only modify their own resources
  • •Designed MongoDB schemas optimized for booking queries with proper indexing strategies
  • •Implemented multi-language support system with database-driven translations (EN/AR/HE)
  • •Configured ALB and Auto Scaling Groups with Launch Templates for elastic, highly available backend deployment
  • •Designed VPC with public/private subnets and NAT Gateway for secure network segmentation and outbound access
  • •Integrated AWS Secrets Manager for credentials and configuration, and AWS S3 for media storage
  • •Integrated OpenAI API for chatbot functionality and maintained production monitoring and debugging workflows

Architecture

Layered architecture with separation of concerns: REST controllers handle HTTP requests, service layer contains business logic, repository layer manages data access. AWS infrastructure uses ALB in front of Auto Scaling Groups backed by Launch Templates, with application instances in private subnets and NAT Gateway for controlled outbound traffic. Secrets and credentials are managed through AWS Secrets Manager. MongoDB supports flexible schema design for multiple booking models.

Impact

Successfully handles complex booking scenarios with data consistency guarantees and secure multi-tenant access. The AWS architecture supports horizontal scaling, improved availability, and production-grade security patterns suitable for real-world traffic growth.

02 · Project

Minor Mentoring System Project

Graduation Project
Students
Spring MVC
Matcher
MySQL

Problem

University students need effective mentor matching based on skills, career goals, and mentor expertise, with a system to track mentorship progress and task completion.

Solution

Developed a full-stack mentorship platform with intelligent recommendation algorithm that analyzes multiple factors to create optimal mentor-student matches, along with comprehensive task management and progress tracking capabilities.

Tech stack

Backend

JavaSpring FrameworkSpring Security

Database

JPA/HibernateMySQL

Frontend

HTMLCSSBootstrap

Role

  • •Designed and implemented recommendation algorithm using skill-based matching and career goal analysis
  • •Built RESTful APIs for mentor-student matching, task management, and progress tracking
  • •Developed secure authentication and authorization system with Spring Security
  • •Designed database schema optimized for recommendation queries
  • •Integrated with university systems for student data synchronization

Architecture

Traditional MVC architecture with Spring Framework. Service layer implements recommendation algorithm, repository layer uses JPA for data persistence. RESTful API design with clear separation between matching logic and task management.

Impact

Successfully matches students with relevant mentors based on multiple criteria. Task management system enables structured mentorship programs with measurable outcomes.

Experience

Where I've shipped

Current08/2022 - Present

Backend Software Engineer (C)

ProGineer Technologies

Full-time

Key responsibilities

  • •Develop and maintain backend services written in C for production systems, focusing on performance-critical and memory-sensitive components
  • •Contributed to 5+ major projects and numerous bug fixes, working within a team of 20 engineers to deliver enterprise solutions
  • •Optimized critical database queries, reducing execution time from ~2 hours to 1-4 seconds (99.9% improvement), significantly enhancing system performance
  • •Work with databases containing millions of records, managing 100+ tables across multiple schemas and collaborating in designing 20 new tables for 2 major projects
  • •Resolved 10-15+ production incidents and performance enhancements, including successful on-premise performance optimization for Asian customer that resulted in high satisfaction
  • •Handle production issues and system debugging in challenging environments, including on-premise deployments with no cloud access, requiring deep system-level analysis
  • •Work with Cassandra NoSQL systems for distributed data modeling, focusing on scalability and availability
  • •Built and extended data generation pipelines across multiple system areas to produce search-ready documents for OpenSearch indexing
  • •Participated in designing structured document payloads for OpenSearch, including field normalization and denormalization to support efficient search and retrieval
  • •Collaborated on integrating generated data into OpenSearch storage workflows, keeping source systems and search indexes aligned
  • •Collaborate with cross-functional engineering teams on backend design and system behavior decisions

Technologies

COracle SQLCassandra NoSQLOpenSearchInformix
Project

Software Engineer

Bloom – Venue Booking Platform

Personal Project

Bloom is a booking and management platform for chalets, wedding halls, and event venues. The system enables users to browse venues, check availability, and make reservations with support for different booking models (full-day bookings, time-based reservations, and event-based bookings). Recently evolved the deployment into a scalable AWS architecture with load balancing, auto scaling, and secure networking.

Key responsibilities

  • •Designed and implemented core backend logic and REST APIs, handling booking workflows, validation, and business rules
  • •Designed database schemas and domain models with MongoDB, optimizing queries and indexes for performance-critical booking operations
  • •Configured Application Load Balancer (ALB) to distribute traffic across backend instances for high availability
  • •Set up Auto Scaling Groups with Launch Templates to scale capacity based on demand
  • •Designed VPC architecture with public and private subnets, using NAT Gateway for secure outbound access from private workloads
  • •Integrated AWS Secrets Manager for secure storage and retrieval of application credentials and configuration
  • •Managed media storage with AWS S3 and handled server-side debugging, logs, and production issues for backend stability
  • •Contributed to backend and infrastructure design decisions, evolving from a single-instance setup to a production-oriented AWS deployment

Technologies

Backend

JavaSpring BootRESTful APIs

Database

MongoDB

Infrastructure

AWS EC2AWS S3ALBAuto ScalingLaunch Templates

Networking

VPCPublic/Private SubnetsNAT Gateway

Security

AWS Secrets Manager

Environment

Linux
View on GitHub →

Learning

Always sharpening

Practice

Continuous learning for production backend work — not buzzwords.

Focus areas

  • ▸Advanced Database Optimization
  • ▸Microservices Architecture
  • ▸System Performance Tuning
  • ▸Search indexing pipelines

Technologies

  • ▸AWS Networking & Auto Scaling
  • ▸Secrets Management
  • ▸Container Orchestration
  • ▸Advanced SQL Techniques

Contact

Let's build something solid

Contact information

Prefer email or LinkedIn — happy to talk systems, architecture, and interesting problems.

Emailahmad.sa893@gmail.comPhone+970 597 267 624

Connect

LinkedInGitHub