Diego Santos
Diego Santos

Software development, automation and AI for evolving operations

Diego Santos

I design and build digital products, systems and automations for operations that need more clarity, scale and control.

Founder ofHaruna Technologies
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I build things.

What do I work with?

Software Engineering

Software (Software & Products)

I build software end to end: web and mobile applications, custom systems, APIs and platforms, from the first sketch to production. Clean architecture, code that lasts and performance you can feel in use.

  • Web, mobile and custom systems
  • Microservices and APIs designed to evolve
  • Clean, tested, maintainable code
  • Performance and continuous delivery
Automation & Applied AI

AI (Artificial Intelligence & Automation)

Automation and AI in service of the operation: from the simple flow that removes repetitive work (integrations, routines, alerts, billing) to agents and copilots that understand context, use your data and do the work. From prototype to production, with quality, security and cost under control.

  • Integrations and routines that remove repeated tasks
  • Agents and copilots that carry out the work
  • Language models connected to your data
  • Evaluation, security and cost under control
DevOps & Cloud

Cloud (Cloud & Infrastructure)

Infrastructure as code, cloud-native architecture and high availability. I work across the big clouds and local providers alike, picking by what the project actually needs rather than by what is fashionable.

  • AWS, GCP, Azure, IBM and Oracle
  • Local providers such as Hostinger and HostGator
  • Infrastructure as code and containers
  • Observability and high availability
AppSec & Hardening

Security (Information Security)

Security treated as part of building, not as a final step. Authentication, permissioning and audit trails in everything I ship, plus event analysis and offensive testing to find the flaw before someone else does.

  • Authentication, permissioning and audit trails
  • Secret management and environment hardening
  • SIEM, firewall and event analysis
  • Pentesting and vulnerability analysis
SaaS Architecture

SaaS (SaaS & Platforms)

Design and evolution of multi-tenant Software-as-a-Service products, integrating billing, reconciliation and analytics dashboards.

  • Per-customer tenant isolation
  • Billing and reconciliation
  • Analytics dashboards
  • A product built to grow
From quick fixes to strategy

Consulting (Consulting & Technical Support)

From urgent to strategic. Need a site or app put online, DNS, email or SSL sorted out, or an outage in your infrastructure fixed? I handle it, straight to the point. When the problem is bigger: architecture diagnosis, technical decisions with criteria, modernization and engineering mentoring.

  • Site or app online, with domain, DNS and SSL
  • Fixing infrastructure, email and performance issues
  • Architecture diagnosis and decisions with criteria
  • Legacy modernization and mentoring
01Capabilities

I build solutions that solve real problems.

Every project is approached with engineering rigor: clean code, sustainable architecture and a direct focus on operational impact.

  • Software Engineering

    Software & Products

    I build software end to end: web and mobile applications, custom systems, APIs and platforms, from the first sketch to production. Clean architecture, code that lasts and performance you can feel in use.

    • Web, mobile and custom systems
    • Microservices and APIs designed to evolve
    • Clean, tested, maintainable code
  • Automation & Applied AI

    Artificial Intelligence & Automation

    Automation and AI in service of the operation: from the simple flow that removes repetitive work (integrations, routines, alerts, billing) to agents and copilots that understand context, use your data and do the work. From prototype to production, with quality, security and cost under control.

    • Integrations and routines that remove repeated tasks
    • Agents and copilots that carry out the work
    • Language models connected to your data
  • DevOps & Cloud

    Cloud & Infrastructure

    Infrastructure as code, cloud-native architecture and high availability. I work across the big clouds and local providers alike, picking by what the project actually needs rather than by what is fashionable.

    • AWS, GCP, Azure, IBM and Oracle
    • Local providers such as Hostinger and HostGator
    • Infrastructure as code and containers
  • AppSec & Hardening

    Information Security

    Security treated as part of building, not as a final step. Authentication, permissioning and audit trails in everything I ship, plus event analysis and offensive testing to find the flaw before someone else does.

    • Authentication, permissioning and audit trails
    • Secret management and environment hardening
    • SIEM, firewall and event analysis
  • SaaS Architecture

    SaaS & Platforms

    Design and evolution of multi-tenant Software-as-a-Service products, integrating billing, reconciliation and analytics dashboards.

    • Per-customer tenant isolation
    • Billing and reconciliation
    • Analytics dashboards
  • From quick fixes to strategy

    Consulting & Technical Support

    From urgent to strategic. Need a site or app put online, DNS, email or SSL sorted out, or an outage in your infrastructure fixed? I handle it, straight to the point. When the problem is bigger: architecture diagnosis, technical decisions with criteria, modernization and engineering mentoring.

    • Site or app online, with domain, DNS and SSL
    • Fixing infrastructure, email and performance issues
    • Architecture diagnosis and decisions with criteria

Company & Operations

Haruna Technologies

Haruna is my independent engineering company. It is the vehicle through which I design, build, and operate mission-critical systems, artificial intelligence, and cloud infrastructure for clients and proprietary products.

Software, AI, cloud and security, from the first diagram through to running in production.

Visit Haruna

Pillars

  1. 01

    Engineering

  2. 02

    Architecture

  3. 03

    Security

  4. 04

    Scale

How I work

No unnecessary management layers or middlemen: direct engineering, security designed from the initial blueprint, and architecture built not to become a bottleneck when business scales.

  1. 01 Understand
  2. 02 Architect
  3. 03 Build
  4. 04 Secure
  5. 05 Operate
  6. 06 Scale
03What I have built

Things I have built.

Products that are up and running, and websites built for businesses, companies and ideas.

Products
See details
Now Haruna KanshiProduction

Olly

Monitoring and operations platform with fully customizable dashboards, intelligent alerting, ticket management and an AI that acts inside the operation.

  • Dashboards built from scratch, with maximum customization
  • Monitoring as close to real time as possible
  • Intelligent alerting system
  • Ticket management, change management and knowledge base modules

Olivia

Olly's artificial intelligence, wired into every module. It does not suggest: it acts. It opens and summarizes tickets, reads and writes documentation, and reaches the right person by email, message or phone call when an event happens. An alert fires and Olivia has already opened the ticket, described the initial problem and called whoever fixes it.

See details
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Academy managementProduction

Kiso

Management system for martial arts academies of any discipline, with both sides on the same platform: instructor and student.

  • Financial control, income statement, tuition and overdue payments
  • Belt progression system with digital certificate
  • Championship organization and academy schedule
  • Product sales through the platform

Flexible attendance

Attendance was built to adapt to the instructor, not the other way around. It works by manual check-off, by a QR Code generated and rotated for each class, by live check-in with a camera doing facial identification on entry and exit, and by facial recognition on training photos, which marks attendance automatically for whoever shows up in the image.

See details
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User data hidden on purpose, to protect people's information.

B2B prospectingProduction

Kizuna Leads

Brazilian B2B prospecting tool that combines federal tax registry data, its own collection and artificial intelligence to assemble a complete company dossier.

  • Company search with broad prospecting filters
  • Prospecting pipeline and client portfolio
  • Monitoring of partners, capital and online reputation
  • AI for data confirmation and information lookup
See details
See details

User data hidden on purpose, to protect people's information.

Accounting managementProduction

Keiri

Management system for accounting firms: contracts, partners, companies, digital certificates and the finances of transfers and payments.

  • Contract, company and partner management
  • Digital certificate control with A1 expiry alerts
  • Finances covering transfers, payments and alerts
  • Form builder for gathering information
See details
Websites
haruna.pro
Haruna Technologies

Haruna Technologies

Independent engineering company for software, AI, cloud and security.

Visit site
04Automation

Work the system does on its own.

A good part of what I build has no screen: routines that run with nobody watching, from customer support to transaction processing.

01

Customer-facing support

Flows that answer, classify and route without depending on someone being available on the other side.

message receivedanswers or routes
triggeraction
02

Transaction collection and processing

Microservices that ingest, validate and process transactions at volume, decoupled and with delivery guarantees.

batch or eventprocesses and reconciles
triggeraction
03

Payment gateway integrations

Wiring systems to payment providers, handling responses, retries and reconciliation of what was charged.

chargeintegrates and reconciles
triggeraction
04

Alerts that take action

The alert does not stop at a notification. The system opens the ticket, describes the initial problem and reaches the right person by email, message or phone call.

alert eventopens ticket and calls
triggeraction
05

Data collection and enrichment

Routines that pull public and online data, cross it with your own base and warn you when something changes.

scheduled routinecollects, cross-checks, warns
triggeraction
06

Deadline watching

Certificate expiry, transfers, payments. Anything with a tracked date speaks up before it becomes a problem.

date approachingnotifies the decider
triggeraction
05Technology & Engineering

Stack & Tools

Technology is chosen to serve the problem. I work with modern, mature tools to guarantee stability, security and delivery speed.

01

Backend

Distributed systems, resilient APIs and service-oriented architecture.

  • Node.js
  • TypeScript
  • Python
  • Go
  • Java
  • Express
  • REST
  • GraphQL
  • Microservices
02

Frontend & Web

Fast, accessible interfaces focused on usability and performance.

  • Next.js
  • React
  • TypeScript
  • Tailwind CSS
  • Server Components
  • State Machines
03

Data & Storage

Relational and non-relational databases, caching and object storage.

  • PostgreSQL
  • MySQL
  • MongoDB
  • Redis
  • Dragonfly
  • Kafka
  • S3
  • R2
  • MinIO
04

Cloud & Infrastructure

Cloud-native architecture, scalable environments and high availability.

  • AWS
  • GCP
  • Azure
  • IBM Cloud
  • Oracle Cloud
  • Cloudflare
  • Docker
  • Kubernetes
  • Linux
  • Nginx
05

DevOps & CI/CD

Continuous delivery automation, infrastructure as code and testing.

  • Terraform
  • GitHub Actions
  • Ansible
  • Docker Compose
  • Automated Testing
06

Artificial Intelligence

LLM integration, RAG pipelines, embeddings and automation agents.

  • OpenAI
  • Claude
  • Gemini
  • RAG Pipelines
  • Vector Search
  • Prompt Engineering
  • Semantic Cache
07

Security

Layered protection, event analysis, offensive testing and hardening.

  • SIEM
  • Firewall
  • Pentest
  • Hardening
  • OAuth2 / OIDC
  • RBAC
  • Secrets
  • CIS Benchmarks
  • AppSec
08

Observability

End-to-end visibility over health, metrics and auditing.

  • Prometheus
  • Grafana
  • ELK Stack
  • Zabbix
  • Datadog
  • OpenTelemetry
06Technical Expertise

Domains of Practice

Where the experience runs deep: infrastructure, security, reliability and data architecture, backed by the certifications behind each one.

Infrastructure Engineering

01

  • Multi-Cloud Architecture

    Provisioning, governance and resilient deployment across multiple providers, without locking into a single vendor.

    • AWS
    • Google Cloud
    • Azure
    • Oracle Cloud
    • IBM Cloud

  • Linux Systems Administration

    Advanced administration, task automation, process management, fine-grained permissions and server hardening.

    • Linux
    • Bash
    • systemd
    • Hardening

  • Networking & Edge Routing

    Virtual and physical networks, DNS policies, SSH security, tunnels and routing with reverse proxies and API gateways.

    • VPC / Subnets
    • DNS
    • SSH
    • NGINX
    • API Gateway

Security Engineering & DevSecOps

02

  • Defensive Security (Blue Team)

    Infrastructure hardening, WAF, corporate firewalls, endpoint isolation and incident response.

    • WAF
    • Firewall
    • Endpoint Security
    • Incident Response

  • Offensive Security (Red Team)

    Web application penetration testing, controlled vulnerability exploitation and threat modeling within the SDLC.

    • Pentest
    • Threat Modeling
    • OWASP
    • SDLC

  • Governance & Privacy

    Compliance with industry standards, strict privilege control and alignment with Brazil's LGPD.

    • LGPD
    • RBAC
    • Least Privilege
    • Compliance

Reliability Engineering & Observability

03

  • Monitoring & Metrics

    Proactive monitoring, telemetry collection and unified infrastructure dashboards.

    • Prometheus
    • Zabbix
    • Grafana

  • Distributed Logging

    Large-scale log aggregation and ingestion pipelines, with centralized analysis.

    • Grafana Loki
    • Elasticsearch
    • Logstash
    • Kibana

  • Distributed Tracing & APM

    End-to-end tracing and performance auditing across distributed architectures.

    • OpenTelemetry
    • Jaeger
    • O11y

Systems & Data Architecture

04

  • Systems & API Architecture

    RESTful APIs, decoupled microservices and distributed event streaming.

    • REST
    • Microservices
    • Apache Kafka

  • Relational & NoSQL Databases

    Relational modeling, indexing, security and tuning, plus scalable NoSQL structures.

    • PostgreSQL
    • MySQL
    • DynamoDB

  • In-Memory & High Performance

    Advanced caching strategies, pub/sub and ultra-low-latency buffers.

    • Redis
    • Dragonfly
    • Pub/Sub

Certifications & Training

09

Credentials issued by vendors, academic institutions and technical tracks completed end to end.

Official Industry Certifications
  • AWSAWS CertifiedAmazon Web Services
  • CSCOEndpoint SecurityCisco
  • CSCONetworkingCisco
Technical Programs (Complete Tracks)
  • ALUFormação SRE (Site Reliability Engineering)Alura
  • ALUFormação Segurança DefensivaAlura
  • ALUFormação Segurança OfensivaAlura
Academic Specializations
  • FIAPCloud, Administration and Solution ArchitectFIAP
  • FIAPGestão de Infraestrutura de TIFIAP
  • FIAPCybersecurityFIAP
07Direct Contact

Got a problem to solve, a product to build or an idea to get off the ground?

Whether it is designing a new architecture, building a system from scratch or shipping AI pipelines, let's talk.

Message me on WhatsAppsantos.diego@haruna.pro
Other channels:LinkedIn