
Workflow Developer & Tester
Webbing • Finland
**Role & seniority: ** Backend Software Developer (mid-level); expected to support Sr. Developer and pair program.
**Stack/tools: ** Go (primary), Java (acceptable), Temporal workflow (implementation + tests), REST APIs, PostgreSQL (schema/indexing/query plans), Git, CI for tests, Kubernetes (basic), event-driven (RabbitMQ/Kafka/Redis Pub/Sub), Docker (nice), Python (nice), Prometheus (nice), unit/integration testing frameworks (Go testing/Testify/mock), load testing (k6/Locust/JMeter).
**Top 3 responsibilities: **
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Implement Temporal workflow activities (HSS adapter, PCRF adapter, inventory updates) and the full provisioning flow.
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Build/maintain Inventory Management DB (tables, indexes, partitioning ~30M records) and REST endpoints (allocate/reserve/release/query SIM records).
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Develop test coverage: unit tests from day one, integration tests (workflow → mock NE → DB assertions), end-to-end provisioning tests, plus load/stress and CI automation.
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Must-have skills:
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2–4 years backend production development; strong Go fundamentals (Java only if willing to transition).
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REST API development with automated testing.
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PostgreSQL proficiency (indexes, query design, execution plans).
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Strong unit + integration testing mindset; Git collaboration.
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Event-driven architecture experience (RabbitMQ/Kafka/Redis Pub/Sub).
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Basic Kubernetes understanding; ability to execute under technical direction.
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Nice-to-haves:
- Workflow engines (Temporal/Camu
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.