Workflow Developer & Tester

Webbing; Warszawa; Remote; PLN 180,000 - 240,000; Full time

Benefits offered by this job

Fully remote

Job summary

Webbing is seeking a senior backend engineer to own core workflow development using Go, with a focus on API design, testing, and scalable data handling for a global MVNO platform.

You will implement Temporal-like workflows, build a robust Inventory DB, and automate tests end-to-end. The role emphasizes collaboration, pair programming, and delivering a greenfield, international remote platform.

Qualifications

• 2–4 years backend development in production environments.
• Go or Java with Go preferred; willingness to transition to Go.
• REST API development for services consumed by automated tests.
• PostgreSQL—designs, indexes, and query plans.
• Strong focus on unit and integration testing.
• Git-based collaboration and code reviews.
• Experience with event-driven architectures (RabbitMQ, Kafka, Redis).
• Basic Kubernetes knowledge and containerized workloads.
• Fluent English communication.

Responsibilities

• Implement Temporal workflow activities in Go and related adapters.
• Build and validate unit tests for all workflow activities from day one.
• Create Inventory Management DB schema, indexes, and partitioning for large scale data.
• Develop bulk import tooling for large data ranges from vendors.
• Expose REST API endpoints for Inventory DB operations (allocate, reserve, release, query).
• Support Sr. Developer with workflow tasks; pair programming expected.
• Develop end-to-end test suites for provisioning flows.
• Conduct load and stress testing across systems.
• Integrate test automation into CI pipelines.
• Add MNP hooks in Inventory DB; assist UAT and regression testing.

Skills

Go

Java

REST API development

PostgreSQL

Unit & integration testing

Git

Messaging (RabbitMQ/Kafka/Redis)

Kubernetes

English fluency

Docker

Tools

Docker

PostgreSQL tooling

Job description

• Implement Temporal workflow activities in Go: HSS adapter, PCRF adapter, Inventory update.
• Build and validate unit tests for all workflow activities from day one.
• Build the Inventory Management Database: tables, indexes, partitioning for 30M records.
• Build bulk import tooling: CSV → ICCID/IMSI/MSISDN range ingestion from vendor.
• Implement REST API endpoints for Inventory DB (allocate, reserve, release, query SIM records).
• Support Sr. Developer on all workflow development tasks — pair programming expected.
• End-to-end test suite: full provisioning flow from SIM activation to order closed.
• Load and stress testing: simulate peak TPS provisioning against all systems.
• Test automation: CI pipeline integration for all workflow and API tests.
• MNP (number portability) hooks in Inventory DB.
• UAT support: reproduce bugs, write regression tests, validate fixes.

• Implement Temporal workflow activities in Go: HSS adapter, PCRF adapter, Inventory update.
• Build and validate unit tests for all workflow activities from day one.
• Build the Inventory Management Database: tables, indexes, partitioning for 30M records.
• Build bulk import tooling: CSV → ICCID/IMSI/MSISDN range ingestion from vendor.
• Implement REST API endpoints for Inventory DB (allocate, reserve, release, query SIM records).
• Write integration tests: workflow → mock NE → database assertions.
• Support Sr. Developer on all workflow development tasks — pair programming expected.
• End-to-end test suite: full provisioning flow from SIM activation to order closed.
• Load and stress testing: simulate peak TPS provisioning against all systems.Test automation: CI pipeline integration for all workflow and API tests.
• HSS sync integration: IMSI allocation state reflected in HSS (mock → real NE).
• MNP (number portability) hooks in Inventory DB.
• UAT support: reproduce bugs, write regression tests, validate fixes.

Requirements:

Must Have

• 2–4 years backend software development in production environments.
• Go or Java — primary development language for this role is Go.
• Java accepted if strong fundamentals and willing to work in Go (we will support the transition).
• REST API development — building APIs consumed by other services and tested by automated suites.
• PostgreSQL — table design, indexes, writing queries, understanding query plans .
• Unit and integration testing — writing tests is a first-class responsibility, not an afterthought.
• Git — branching, pull requests, code review participation.
• Experience with event-driven architectures using RabbitMQ, Kafka, or Redis Pub/Sub.
• Basic Kubernetes knowledge — understanding how your workloads are deployed.
• Ability to work under technical direction of a senior lead and execute quickly.
• Fluent English.

Strong Advantage

• * Any workflow engine experience: Temporal, Camunda, Apache Airflow, AWS Step Functions.
• * Telecom or BSS/OSS background — understanding of SIM lifecycle, provisioning, activation.
• * Test framework experience: Go testing, Testify, mock frameworks.
• * Load testing tools: k6, Locust, JMeter — running and interpreting results.
• * Docker — building and running containerised services.
• * Experience with event-sourced or append-only database patterns.

Nice to Have

• Temporal.io SDK experience — even personal/side project counts.
• Python — useful for scripting, test tooling, data processing.
• Prometheus — understanding how to instrument code with metrics.
• Telecom protocol familiarity: Diameter, SS7, SMPP.

About Webbing:

Founded in early 2010, Webbing is a global data MVNO that delivers enterprise grade, global connectivity and IoT services across more than 200 countries and 600+ mobile carriers' networks. Webbing's secured network delivers network protection and web content intelligence.

Enterprise customers can manage, monitor, and optimize data usage in real-time with Webbing's powerful software platform. Gain visibility by application type and have the power to white list applications and limit non-business applications with the click of a button, saving money and improving compliance.

What we offer:

• Fully remote
• An exciting and challenging greenfield platform with great skill and knowledge development opportunities.
• The opportunity to join a team of highly professional specialists in an international environment.
• The opportunity for professional development within a reputable international innovative and growing company.