Remote Backend Developer jobs open to Spain.

Java · AWS

Java, Spring Boot, Microservices, Event-driven architecture, Kafka, High-integrity transactional systems, REST APIs, AWS, Secure coding practices, AI tools, EVM-compatible networks, Stablecoin issuance, Compliance tooling, FinTech experience

BVNKBVNK is a UK-based fintech B2B platform specializing in stablecoin payment infrastructure, enabling businesses to send, receive, and convert currencies globally.

TypeScript · Go

5+ years backend services in production with on-call, TypeScript or Golang, OAuth/OIDC/JWT, PostgreSQL

SupabaseSupabase is a Postgres development platform providing databases, authentication, storage, APIs and related developer tools.

Python · Kotlin · AWS

8 years of experience, Python, Kotlin, AWS, MySQL, Kubernetes, Correctness-sensitive systems, Data-processing systems, Cross-team collaboration, Technical strategy development, On-call operations management

AffirmAffirm operates a payment network that gives consumers flexible ways to pay and helps merchants grow.

React · Vue · Python

1.5 years of experience, Python, Kotlin, React, Vue, Declarative UI frameworks, Mobile application development, Code review, Debugging, Collaboration with product management, Agile methodology

AffirmAffirm operates a payment network that gives consumers flexible ways to pay and helps merchants grow.

Python

6-7+ years commercial development, Python 3.x, Django, high-load systems, fluent Russian, intermediate+ English

TorreroTorrero provides white-label casino and sportsbook platforms and B2B game aggregation for iGaming operators.

Python

5+ years commercial development, Python 3.x, Django, high-load systems, fluent Russian, intermediate+ English

TorreroTorrero provides white-label casino and sportsbook platforms and B2B game aggregation for iGaming operators.

Python · Go · Kubernetes

5 years of experience, Golang, Python, Kubernetes, AI-assisted coding, Distributed systems

Lemon.ioLemon.io is a Ukraine-based B2B platform connecting startups with vetted freelance developers, offering services globally across various sectors.

Go

Golang or comparable backend language, distributed systems, Kafka, Pub/Sub or SQS messaging

CyberhavenCyberhaven provides an AI-native data security platform for protecting data across human and AI-agent workflows.

Python · SQL · Azure

4 years of experience, Python, FastAPI, Azure, Databricks, REST APIs, SQL Server, Docker, Asynchronous processing, Messaging systems, CI/CD

Mutt DataMuttdata is a data and AI consultancy that builds data platforms and machine learning systems, such as forecasting and recommendation models, for client companies.

Python · SQL · Azure

4 years of experience, Python, FastAPI, Azure Databricks, Asynchronous processing, SQL Server, Docker, Azure services, CI/CD participation

Mutt DataMuttdata is a data and AI consultancy that builds data platforms and machine learning systems, such as forecasting and recommendation models, for client companies.

Node.js

5+ years backend with Node.js in production, distributed systems, PostgreSQL tuning, observability

SupabaseSupabase is a Postgres development platform providing databases, authentication, storage, APIs and related developer tools.

3+ years Haskell, C, PostgreSQL/plpgsql, open-source contributions, Linux debugging

SupabaseSupabase is a Postgres development platform providing databases, authentication, storage, APIs and related developer tools.

Python · Java · AWS

Java, Python, C++, AWS, Distributed systems, Production backend service ownership, Fluent English, Cloud integration with HPC, Simulation-specific solutions, High-performance computing optimization

Rust · AWS · Kubernetes

Rust, Postgres compatibility, Deterministic Simulation Testing, Formal verification methods, Fuzz testing, Differential testing, AWS, Kubernetes, Embedded databases, Remote team collaboration, Cloud systems observability, Cloud systems reliability, Cloud systems performance

SupabaseSupabase is a Postgres development platform providing databases, authentication, storage, APIs and related developer tools.

Python · GCP

5 years of experience, Python, Bash, Data pipelines, Large-scale data processing, Cloud infrastructure, GCP, Terraform, Web crawlers, Audio processing

SpeechifySpeechify is an AI-powered text-to-speech SaaS platform headquartered in the US, focusing on accessibility and productivity for a global audience.

Python · GCP

5 years of experience, Python, Bash, Data pipelines, Large-scale data processing, Cloud infrastructure, GCP, Terraform, Web crawlers, Audio processing

SpeechifySpeechify is an AI-powered text-to-speech SaaS platform headquartered in the US, focusing on accessibility and productivity for a global audience.

TypeScript · Python · Java

Open Source Contributions, Backend Development and API Design, Python, Java, C++, Go, Rust, TypeScript, Debugging and Troubleshooting, Automated Testing and Code Validation, Performance Optimization

Weekday AIWeekday provides AI-assisted candidate sourcing and recruiting services for employers.

Python · Kotlin · AWS

2+ years software engineering, backend in Python or Kotlin, AWS, MySQL, Kubernetes, on-call rotation

AffirmAffirm operates a payment network that gives consumers flexible ways to pay and helps merchants grow.

JavaScript · Rust · AWS

3 years of experience, PostgreSQL Expert, Nix packaging, Ansible, Docker, AWS, Kubernetes, C/C++ builds, Go, JavaScript, Rust, Infrastructure management, Customer engagement, Proactive problem-solving

SupabaseSupabase is a Postgres development platform providing databases, authentication, storage, APIs and related developer tools.

7 years of experience, Advanced modern C++ (C++23 or newer), Large-scale C++ codebases, Memory management, Concurrency, Performance profiling, Experience shipping software to a large consumer audience, Comfort with large build systems, Algorithms and data structures

DuckDuckGoDuckDuckGo is a Paoli, Pennsylvania-based privacy technology company offering a privacy-focused search engine and browser solutions for a global audience.

Python · SQL

5+ years software/data/ML engineering, production LLM apps, semantic search, ranking metrics, Python and SQL

ParserParser provides software engineering and product-development teams for digital businesses.

Python · SQL · Azure

6+ years backend engineering, Python and REST APIs, SQL and NoSQL, CI/CD, Azure preferred

ParserParser provides software engineering and product-development teams for digital businesses.

Python

5 years of experience, Trust & Safety systems, Python, Distributed systems, Cloud applications, End-to-end system ownership, APIs design, Collaboration with non-technical stakeholders, Problem-solving in ambiguous situations

ElevenLabsElevenLabs builds AI voice, conversational-agent, creative-media, and developer API products.

Python · Go · AWS

6 years of experience, Golang, Python, Event-driven systems, CI/CD tooling, Web application security, SAST/SCA/secret-scanning tooling, AI-assisted engineering, AWS, Kubernetes, Fintech experience, PCI DSS knowledge, Software supply-chain integrity, Policy-as-code familiarity, Threat modeling

SezzleSezzle is a payments platform offering installment plans, credit-building and rewards features to shoppers while connecting merchants to its customer network.

Python · Go · AWS

6 years of experience, Golang, Python, Event-driven systems, CI/CD tooling, Web application security, SAST/SCA/secret-scanning tooling, AI-assisted engineering, AWS, Kubernetes, Fintech experience, PCI DSS knowledge, Software supply-chain integrity, Policy-as-code familiarity, Threat modeling

SezzleSezzle is a payments platform offering installment plans, credit-building and rewards features to shoppers while connecting merchants to its customer network.

Python · Kubernetes

Python, Backend development, Software design patterns, Cloud infrastructure, Test design, Security fundamentals, Authentication/authorization experience, Kubernetes, Internal platform development

ElevenLabsElevenLabs builds AI voice, conversational-agent, creative-media, and developer API products.

Rust

Rust, Backend engineering, System reliability, Scalable systems, UI systems design, Data pipelines, Project leadership, Professional editing tools

ElevenLabsElevenLabs builds AI voice, conversational-agent, creative-media, and developer API products.

SQL

10 years of experience, ABAP4, ABAP OO, AI-driven development, SAP add-on development, SQL optimization, XBP, XMI, RFC programming, German fluency, Technical architecture ownership, Job scheduling expertise

StonebranchStonebranch is an Atlanta-based B2B SaaS provider specializing in IT automation and orchestration solutions for enterprises across industries such as financial services, healthcare, and technology.

Rust · SQL · AWS

5 years of experience, Rust, async Rust, Tokio, performance profiling, memory management, production-grade services, SQL/NoSQL databases, Docker, Linux, cloud provider (AWS/GCP/Azure)

Python

Python scraping of Google or protected sites, Playwright/Selenium, HTTP/TLS, anti-bot and CAPTCHA handling

AdthenaAdthena is an AI-powered search intelligence platform giving brands, marketers and agencies competitive insight into the paid search market.