
Workflow Developer & Tester
Webbing • Amsterdam, North Holland, Netherlands
-
Role & seniority
-
Backend software development role; mid-level (2–4 years), Go-focused
-
Works under technical direction of a senior lead; pair programming expected
-
-
Stack / tools
-
Go (primary); Java acceptable with willingness to transition to Go
-
Temporal workflow activities/SDK; workflow→NE integration testing
-
REST API development
-
PostgreSQL (schema, indexes, query planning/performance)
-
Event-driven: RabbitMQ / Kafka / Redis Pub-Sub
-
Kubernetes basics
-
Git (PRs/review participation)
-
Testing/CI: unit + integration + end-to-end + load/stress; CI pipeline integration
-
Optional: Docker, Prometheus, Python, load tools (k6/Locust/JMeter)
-
-
Top 3 responsibilities
-
Implement Temporal workflows (Go) and corresponding workflow activities (HSS, PCRF, inventory updates) with unit tests from day one
-
Build/operate Inventory Management DB (tables/indexes/partitioning for ~30M records) and REST APIs for SIM lifecycle operations (allocate/reserve/release/query)
-
Create integration + end-to-end + load testing (workflow → mock NE → DB assertions; full provisioning flow; peak TPS simulation)
-
-
Must-have skills
-
2–4 years production backend experience
-
Go or Java (with Go transition)
-
REST API development with automated testing
-
PostgreSQL proficiency (schema/indexes/queries/query plans)
-
Strong unit/integration testing discipline
-
Git workflow a
-
Full 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).
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.