+ Senior Software EngineerBARCELONA, ES ↗

Amin
Chouaibi.

Backend / Vertical Slice Architecture / Distributed Systems

I’m a software engineer drawn to backend and distributed systems. I like understanding how things work, turning complex problems into code I can reason about, and testing my ideas by building.

Explore my work Read my writing

Amin Chouaibi8+ years in engineering / Based in Barcelona

IN MY NOTEBOOK

I write about what I build, what fails and what I learn along the way. Browse my writing ↗

A closer look

01 / PROJECTS

What I build.

Wyrd, Rate Limiter Lab and TelcoLab. Three projects where I build, test and write about the systems I want to understand.

PERSONAL PROJECT / OPEN SOURCE

Wyrd

Deterministic event-driven processes for .NET.

A framework I’m building to keep business decisions visible while the runtime handles retries, compensation and idempotency.

Pure domain decisions and declarative sagas
Compile-time checks with Roslyn analyzers
Skuld: reproducible failure simulation

Explore the code Documentation

Preview · in-memory runtime available; durable runtime in development.

REAL CODE FROM THE SHOP SAMPLEC#

samples/Shop/Fulfillment/OrderFulfillment.cs

1public static Process OrderFulfillment => Process
2    .StartOn<OrderPlaced>(e => e.OrderId)
3    .Then(Stock.Reserve).Retry(5.Times).Undo(Stock.Release)
4    .Then(Payments.Charge)
5        .Retry(5.Times, Backoff.Exponential)
6        .Undo(Payments.Refund)
7    .Await<PaymentConfirmed>(e => e.OrderId).Within(15.Minutes)
8    .Then(Shipping.Ship).Retry(5.Times)
9    .OnCompensated(Orders.Cancel).Retry(5.Times);

PERSONAL PROJECT / GO

Rate Limiter Lab

A production spike took down a reverse proxy and left me with a question: what actually happens inside a rate limiter? I built five algorithms from scratch and put them under the same load.

Steady · ns/op
Algorithm	ns/op	Memory
Token Bucket	13.7	O(1)
Fixed Window	11.9	O(1)
Leaky Bucket	24.0	O(1)
Sliding Log	40.2	O(n)
Sliding Counter	18.6	O(1)

Published benchmarks · Intel i7-13700F · Go 1.22. Lower ns/op is better.

HTTP gateway, Go load generator, race tests, k6 and kind. Shared state with Redis is the next step.

Code Results & methodology Read the article on LinkedIn

PERSONAL PROJECT / CODE + ARTICLES

TelcoLab

One workflow. Two architectures.

I rebuilt number porting with Microsoft Orleans to compare virtual actors with a classic queue-driven architecture. Then I wrote about what I learned, including where Orleans is the wrong choice.

Grains, streams, Postgres, transactions and observability with OpenTelemetry.

Explore the article series

Read the series on LinkedIn. Articles in English and Spanish.

Code All articles on LinkedIn

PROFESSIONAL PROJECTS

PROFESSIONAL PROJECTSSelect a project to see my contribution.

Professional work · source code is not public

PRODUCT ENGINEERING · 202601

eMobility

Product back-office & operations

WHAT I WORKED ON

Built the domain’s first product back-office and an operations hub. Refactored 35k+ lines across the ecosystem, including billing, and worked on OpenTelemetry / Grafana alerts and Databricks ETLs.

DELIVERABLES & RESPONSIBILITIES

First product back-office
Operations hub with role-based access
Billing refactor & architectural decisions
Telemetry, integration tests & ETLs

02 / WRITING

What I learn,
what I write.

Code, technology and the people behind it. Experiments and reflections on building software and working together.

All writing

Rate limitingEN

When the gateway fell over

What I learned by building five rate-limiting algorithms and putting them under the same load.

ArticleLinkedIn

TelcoLab / 00EN

Actors vs queues: the starting point

The same number-porting workflow built with queues and virtual actors. What each approach makes easier, and what it asks you to own.

ArticleLinkedIn

ReflectionsES

The model is not deterministic. The program it wrote is.

Using AI to build verifiable tools instead of trusting its conclusions. A reflection on evidence, engineering judgment and checks that outlive a conversation.

ReflectionLinkedIn

03 / THE JOURNEY

My engineering
journey.

From my first production deployments to enterprise platforms. Each chapter added a new way of looking at the problem.

2026
eMobility↳Lidl Connect↳Backend & Platforms
NOW
Jan 2026 — Present
Schwarz Digits
Barcelona, Spain (hybrid)
Backend and platform engineering at Schwarz Digits, with experience across EV charging and telecom operations in the Lidl Plus ecosystem.
Explore this chapter+
Oct 2026 — Present
Senior Software Engineer · Backend & Platforms
Backend engineering and system design, with a focus on maintainable and reliable software
Technical exploration and evaluation of architectural alternatives
C#.NETSystem Design
May 2026 — Oct 2026
Senior Software Engineer · Lidl Connect
Helped build the foundations of a pan-European mobile service within a cross-functional task force, connecting the product to the Lidl Plus ecosystem
Turned operational needs into a PRD and architecture for a new SaaS covering country configuration and workflows for Support, Product and Engineering; handed the design over for implementation
Designed service integrations around Sagas, the Outbox pattern and RabbitMQ to keep distributed workflows consistent and resilient
Owned load and performance testing to assess throughput and resilience before launch
Event-Driven ArchitectureRabbitMQSagasOutbox PatternPerformance Testing
Jan 2026 — May 2026
Senior Software Engineer · Lidl Plus eMobility
Built the charging domain's first product back-office and documented how it works, giving teams a shared reference for operating and evolving the product
Refactored 35k+ lines across the charging ecosystem, including billing, and captured design and maintenance decisions in an ADR
Built an operations hub with role-based and network-scoped access for Country Managers, rollout, Support and Engineering
Made services easier to operate with integration tests, structured logs and OpenTelemetry / Grafana alerts; built Databricks ETLs for analytics
Worked with Product and other departments to turn technical constraints into shared decisions
C#.NETTypeScriptNext.jsSTACKITNATS JetStreamPostgreSQLOpenTelemetryGrafanaDatabricks
2022
Capterra↳GetApp↳Software Advice
May 2022 — Nov 2025
Gartner Digital Markets
Barcelona, Spain
Reviews Platform team powering all Gartner Digital Markets marketplaces (Capterra, GetApp, Software Advice). Processing millions of software reviews to generate reliable, actionable insights.
Explore this chapter+
Oct 2024 — Nov 2025
Senior Software Engineer
Led junior and mid-level engineers, conducting technical interviews and code reviews
Defined and implemented transversal architectural standards across squads
Led complex initiatives spanning multiple teams and impacting business metrics
Drove the Updated Reviews initiative with SEO and Sites teams to improve organic visibility
Led efforts to improve system performance, reliability, and operational efficiency
C#.NET 8.NET 9TypeScriptNext.jsReactPostgreSQLKafkaAWS EKSOpenSearch
May 2022 — Oct 2024
Software Engineer II
Designed and maintained pipelines transforming reviews into quality insights
Led the refactor of the review scoring system into a decoupled, resilient engine
Built gamification systems incentivizing vendors to collect high-quality reviews
Evolved the review moderation platform from Angular to Next.js
Implemented event-driven architectures with Kafka/Confluent Cloud
C#.NET 6TypeScriptAngularNext.jsReactPostgreSQLKafkaAWS
2019
Lidl Plus↳Alerts↳Azure
September 2019 — May 2022
Plain Concepts
Barcelona, Spain
Working on Lidl Plus App project serving more than 60 million users. High-availability backend system based on microservices, cloud, data analysis, and real-time data ingestion.
Explore this chapter+
March 2020 — May 2022
Backend Sr Software Developer
Migrated monolithic systems to microservices in .NET
Worked on Communications squad implementing user promotion and notification systems
Designed and led migration of Alerts system from monolith to microservices
Upgraded systems from .NET Core 3.1 to .NET 6
Implemented CQRS + DDD architectures for critical domains
.NET 6C#Azure FunctionsCosmos DBEvent HubService BusAKSTerraform
September 2019 — March 2020
IT Support Consultant
Built and maintained internal applications for Customer Support
Developed tools supporting the Lidl Plus App ecosystem
Gained foundational experience in enterprise-scale systems
Collaborated with support teams to improve operational efficiency
.NET CoreC#AzureInternal ToolsCustomer Support Systems
2018
Full-stack↳.NET↳React
May 2018 — September 2019
Pasiona Consulting
Barcelona, Spain
Dual internship program and early career development focusing on both Front-end and Back-end development with SharePoint Online and Azure Functions.
Explore this chapter+
June 2019 — September 2019
Junior Developer
Developed SPFx components with React.js in TypeScript for SharePoint Online
Built Azure Functions operating as orchestrators for different services
Worked with multitasking programming and Test Driven Development methodology
Used Azure DevOps: Azure Boards (SCRUM), Azure Repos (Git Flow), Azure Pipelines (CI/CD)
Obtained and analyzed data to assess system capabilities
React.jsTypeScriptSharePoint SPFxAzure FunctionsAzure DevOpsSCRUMTDD
May 2018 — June 2019
Trainee Developer
Dual internship program focusing on full-stack development while studying
Backend development with .NET & .NET Core Framework, ASP.NET & ASP.NET Core
Learned and applied Domain Driven Design paradigm and Test Driven Development
Frontend development with React.js ES6, TypeScript, HTML5
Published and tracked App Services in Azure, implemented comprehensive unit testing
.NET Framework.NET CoreASP.NET CoreEntity FrameworkReact.jsTypeScriptAzure
⌘2018 / FIRST STEPS

04 / HOW I BUILD

Tools follow
the problem.

Vertical Slice Architecture is the approach I use most: I organize code around features and use cases, keeping each change close to the behavior it delivers.

Vertical slices

A use case, end to end: its logic, data access and tests together. Clear domain boundaries, with DDD and CQRS where they help.

C# / .NETASP.NET CoreDDD / CQRSTDD

Messaging & data

Connecting services while keeping failures and consistency in view.

KafkaRabbitMQNATS JetStreamPostgreSQLMongoDB

Cloud & operations

The infrastructure to run it, and the signals to understand it.

AWS / Azure / STACKITKubernetesTerraformOpenTelemetry

Product & platforms

Useful internal tools, thoughtful interfaces and room to explore AI.

TypeScriptReact / Next.jsAI GatewaysAgent orchestration

AMIN CHOUAIBI EL AZAARBCN ↗

05 / THE PERSON

Curiosity,
in production.

I’m Amin Chouaibi El Azaar, a software engineer based in Barcelona. I like getting close to the problem, making architecture understandable and helping the people around me build better software. Alongside work, I continue studying Computer Engineering at the UOC.

Education

Engineer's degree, Computer EngineeringUniversitat Oberta de Catalunya · Sep 2021 — Present · In progress

Senior Technician in Crossplatform Application DevelopmentEscola Pia Sant Anna, Mataró · 2017 — 2019

Engineer's degree, Telecommunications EngineeringUniversitat de Barcelona · Sep 2015 — 2017 · Paused

Certifications

EF SET English Certificate 71/100 (C1 Proficient)EF SET · Apr 2025

Security Yellow BeltSecurity Journey · Dec 2024

Hacking For BegginersHackers Academy · Nov 2021

Aplicaciones web en tiempo real con SignalR CoreUdemy · May 2020

.NET Application Security and Secure Coding TrainingCheckmarx · Apr 2022

Languages

SpanishNative

CatalanNative

ArabicNative

EnglishC1 · EF SET 71/100

LinkedIn GitHub

AminChouaibi.

What I build.

Wyrd

Rate Limiter Lab

TelcoLab

eMobility

What I learn,what I write.

When the gateway fell over

Actors vs queues: the starting point

The model is not deterministic. The program it wrote is.

My engineeringjourney.

Schwarz Digits

Senior Software Engineer · Backend & Platforms

Senior Software Engineer · Lidl Connect

Senior Software Engineer · Lidl Plus eMobility

Gartner Digital Markets

Senior Software Engineer

Software Engineer II

Plain Concepts

Backend Sr Software Developer

IT Support Consultant

Pasiona Consulting

Junior Developer

Trainee Developer

Tools followthe problem.