J. Daniel Jiménez, Developer in Madrid, Spain
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J. Daniel Jiménez

Verified Expert  in Engineering

Site Reliability Engineer and Developer

Madrid, Spain
Toptal Member Since
February 11, 2021

Daniel has been an IT professional since 2013, specializing in cloud-based site reliability engineering since 2017. He has also designed platforms at scale to deal with huge numbers in Spanish and European enterprises such as Airbus, BBVA, Telefonica, and Rabobank. Daniel delivers his best when solving problems that others have left behind as "cannot be done." He tackles new challenges with enthusiasm and a can-be-done mindset. Then he delivers high-quality solutions that exceed expectations.


Docker, Kubernetes, APIs, Continuous Delivery (CD), Continuous Integration (CI)...
Infoblox (Freelance)
Splunk, ETL, Python, DNS, Jira, Project Consultancy, Enterprise...
GitHub, Kubernetes, Google Compute Engine (GCE), Ansible, ELK (Elastic Stack)...




Preferred Environment

Google Compute Engine (GCE), Kubernetes, Python, Splunk, Ansible, Git, Node.js, GitLab CI/CD, DevOps, Site Reliability Engineering (SRE)

The most amazing...

...thing I've built is a complete website (front end and back end) with automations to administer it and scale from hundreds of users per hour to thousands.

Work Experience

Site Reliability Engineer

2020 - 2021
  • Designed architecture and pipelines to be used in Kubernetes.
  • Migrated an app from a monolithic legacy architecture to a Kubernetes microservice architecture.
  • Created Docker images from code, using PHP Laravel for the API endpoint and Vue.js for the front end. I also developed background worker processes.
  • Designed and implemented tests to check deployment status and app health.
Technologies: Docker, Kubernetes, APIs, Continuous Delivery (CD), Continuous Integration (CI), GitHub, Site Reliability Engineering (SRE), Site Reliability, Debian, Bash Script, Cloud Infrastructure, Server Infrastructure, Amazon Web Services (AWS), DevOps, Linux, Python, Argo CD

Splunk Developer

2020 - 2020
Infoblox (Freelance)
  • Created dashboards for the corporate Splunk platform.
  • Developed business intelligence dashboards to show high-level information for managers and clients.
  • Created advanced Splunk queries (SPL) and designed advanced data management, using regex.
Technologies: Splunk, ETL, Python, DNS, Jira, Project Consultancy, Enterprise, Cloud Infrastructure, Server Infrastructure, DevOps, Linux

Site Reliability Engineer

2020 - 2020
  • Migrated a Flask API to Google Cloud, covering from code to service, and created Docker images from scratch.
  • Automated code deployment to different environments, using GitHub Actions and Ansible.
  • Designed platform architecture to support a flexible workload.
  • Autoconfigured an external DNS, using an API and Ansible.
Technologies: GitHub, Kubernetes, Google Compute Engine (GCE), Ansible, ELK (Elastic Stack), NGINX, MongoDB, Helm, Docker, Python, uWSGI, Site Reliability Engineering (SRE), Site Reliability, Jira, Bash Script, Debian, Cloud Infrastructure, Server Infrastructure, Linux, Google Cloud, Google Kubernetes Engine (GKE), DevOps

Site Reliability Engineer

2019 - 2020
  • Analyzed the client platform to deliver a working plan to migrate a web app to Kubernetes microservices and designed the new architecture.
  • Created a process to autobuild Docker images from code and push them to an Azure Container Registry.
  • Automated database population and updates, using Python and Bash.
Technologies: Azure, Terraform, GitHub, ELK (Elastic Stack), MongoDB, Kubernetes, Docker, NGINX, Helm, Node.js, Site Reliability Engineering (SRE), Site Reliability, Cloud Infrastructure, Server Infrastructure, Azure Kubernetes Service (AKS), Linux, Python, DevOps, Bash

SRE Lead

2018 - 2020
  • Defined strategies to align the operations of 12 Telefonica security operations centers (SOCs) around the world. The purpose was to create a sense of community, share knowledge, automate toils, and design the architecture to support it.
  • Coordinated actions among SOC managers to get them all on the same page and agree on how they would collaborate.
  • Defined and updated systems architecture, a security rules repository, and procedures, allowing customizations per client needs. All the rules had to be available for all the security information and event management (SIEMs) that were being used.
  • Enabled cloud tools to support the transition: set up repositories, wikis, and Kubernetes to manage internal services; wrote Jenkins automation scripts; and developed a Python API to provide rules info and auto deploy rules to SIEMs (when possible).
Technologies: Cloud, Kubernetes, Splunk, Splunk Enterprise Security, SIEM, AlienVault, Firewalls, Bash, System Architecture Design, Research, People Management, Enterprise, Jira, Bash Script, Cloud Infrastructure, Server Infrastructure, Linux, Python, Docker, DevOps

SRE | Splunk Administrator

2017 - 2018
  • Identified performance problems in the Splunk platform and kept it performing as required.
  • Automated the Splunk production platform administration, using Ansible to scale up and down, update versions, and deploy applications.
  • Created Splunk Docker images and deployed them into a Kubernetes cluster. The goal was to move from a monolithic architecture to a microservices architecture. This worked in a development environment but was not promoted to production.
Technologies: Splunk, Linux, OpenShift, Kubernetes, Ansible, Ansible Tower, Python, Bash, Performance, Git, Scrum, Jira, Enterprise, Cloud Infrastructure, Server Infrastructure, DevOps, Azure, Azure Kubernetes Service (AKS), Docker

Project Manager | DevOps and Developer

2016 - 2017
Deloitte Spain | MAPFRE
  • Developed a Splunk app based on Django to identify potentially fraudulent benefit claims. This was done by looking for activity matching any rule defined by the client and generating alerts.
  • Managed a team of 12 developers, focusing on keeping the client happy by exceeding its expectations by delivering sooner and more than agreed. Retained and kept team members happy by applying our lightweight version of Scrum.
  • Kept the development environment up and running, wrote automation, maintained the GitLab server, and wrote hook scripts to force the Git Workflow and configure CI (development) and CD (production).
  • Paid back the investment in the first year of production by identifying several fraud cases. The company saved millions of euros and I received a double bonus for this work.
Technologies: Django, Server Infrastructure, Enterprise, Regular Expressions, Splunk, Linux, Python, JavaScript, CSS, Bash, Automation, Jenkins, Git, GitLab, Continuous Delivery (CD), Continuous Integration (CI), DevOps, Docker

Developer and Security Analyst

2013 - 2016
  • Took part in a consultancy at Airbus, Toulouse after completing a one-week course in AlienVault.
  • Developed custom dashboards in Splunk for Mexico National Bank.
  • Served as a security analyst and security platforms administrator at Telefónica SOCs.
  • Developed a Django app to build an assets inventory by using SNMP queries and AlienVault actions.
Technologies: AlienVault, Elastic, ELK (Elastic Stack), Performance, Performance Tuning, Server Infrastructure, Enterprise, Regular Expressions, Training & Training Content Development, Training, IT Security, Security Analysis, VPN, Akamai, Content Delivery Networks (CDN), Python, Automation, People Management, Splunk

Co-founder and CTO

2011 - 2014
Wanna WISP
  • Co-founded and secured funding for Wanna, a venture capital wireless ISP intended to bring reliable internet connections to rural areas.
  • Led the design, development, and implementation of the different services needed to make Wanna work. It was a highly open-sourced project.
  • Designed and set up the entire architecture, including accounting servers (FreeRADIUS), LAMP infrastructure, networking, wireless links, corporate web page design, backups, monitoring, improvement, and research.
Technologies: Networking, WiFi, Wireless, 802.1X, OpenLDAP, FreeRADIUS, PHP

Project Manager

2010 - 2011
  • Managed a team of five people that delivered managed security services seven days a week in different shifts.
  • Designed and set up a SIEM architecture and the tools to provide the service. The tools included Redmine, MySQL HA, a firewall, VPN, and a document repository.
  • Ensured the achievement of SLAs by communicating with the customer, supporting the team with any problems that popped up, and improving the service and the ways of working with automation and procedures.
Technologies: MySQL, Server Infrastructure, Regular Expressions, AlienVault, Linux, Bash, Python, Load Balancers, Redmine

IT Security Consultant

2007 - 2010
Grupo Oesía
  • Analyzed security events at the first security operations center (SOC) in Spain, which was part of the managed security services section in Oesía (previously known as IT-Deusto).
  • Designed the infrastructure and performed the initial setup for customers of the new AlienVault service.
  • Developed internal tools and services to speed up repetitive tasks, improve productivity, and make my team members' lives easier.
Technologies: Linux, Red Hat Linux, Check Point, OpenVPN, OSSIM, AlienVault, Iptables, Python, Bash, Debian, MySQL, Project Consultancy, Security Analysis, IT Security, Bash Script

From Code to Microservices

Architected, designed, and implemented the entire API of a web-based app. My work included creating Docker images, configuring storage, networking, Kubernetes clusters, and permissions in GCE via Ansible. I also deployed the API to the proper environment when new code was pushed to that environment branch.
2003 - 2005

Certificate of Higher Education in Software and App Development

IES Venancio Blanco - Salamanca, Spain

JUNE 2020 - JUNE 2023

Certified Kubernetes Administrator (CKA)

Cloud Native Computing Foundation (CNCF)


Splunk Certified Architect (V6)



Node.js, OpenLDAP


Splunk, Git, OSSIM, Google Compute Engine (GCE), Ansible, Elastic, ELK (Elastic Stack), GitHub, NGINX, AlienVault, VPN, OpenVPN, Iptables, Jira, Google Kubernetes Engine (GKE), GitLab CI/CD, Helm, uWSGI, Terraform, Ansible Tower, Jenkins, GitLab, Redmine, Azure Kubernetes Service (AKS), Grafana, Kibana


Bash, Bash Script, Python, Active Server Pages (ASP), PHP, JavaScript, CSS


Linux, Azure, Debian, Kubernetes, Docker, Amazon Web Services (AWS), OpenShift, Red Hat Linux, Amazon


DevOps, Web Architecture, Continuous Delivery (CD), Continuous Integration (CI), App Development, ETL, Automation, Scrum


Google Cloud, MySQL, MongoDB, TempoDB, Elasticsearch


Django, Flask


Site Reliability Engineering (SRE), IT Administration, Site Reliability, Splunk Enterprise Security, Server Infrastructure, Enterprise, Regular Expressions, Kubernetes Operations (kOps), Performance Tuning, APIs, Networking, DNS, Cloud, SIEM, Firewalls, System Architecture Design, People Management, Performance, Cloud Infrastructure, Autoscaling, IT Security, Security Analysis, WiFi, Wireless, Software Analysis, Software QA, Web Development, Research, Training, Akamai, Content Delivery Networks (CDN), 802.1X, FreeRADIUS, Load Balancers, Check Point, Project Consultancy, Training & Training Content Development, Argo CD, GitOps, Coding, Prometheus, OpenTelemetry, Distributed Tracing

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