5G rollout QA and test automation for a Vietnamese telecommunications operator

Client profile

The client is a major Vietnamese national telecommunications operator serving over 32 million mobile subscribers and 4.8 million broadband customers across all 63 Vietnamese provinces. The operator was rolling out 5G services to 25 major cities during the engagement period, requiring extensive integration with existing 4G infrastructure, customer billing systems, and government regulatory reporting. The client's in-house IT team of 380+ was leading the rollout but had limited automated test capacity.

The challenge

The client's 5G rollout program required simultaneous coordination across radio access network integration, core network provisioning, billing system integration, customer app updates, and regulatory reporting to the Ministry of Information and Communications. Each release cycle involved 40+ engineering teams and touched thousands of test scenarios. Automated test coverage across the release pipeline was 34% at engagement start, with the remaining 66% covered by manual testing that could not keep pace with release frequency.

Production defect leakage was a real business risk. In Q4 2025, three separate 5G launch incidents in Ho Chi Minh City, Hanoi, and Da Nang were traced to release-time regression failures that manual testing had missed. Each incident triggered mandatory customer compensation, negative press coverage, and formal explanations to the Ministry of Information and Communications. The board and CEO had made 5G rollout quality a top-3 corporate priority.

The client had considered three internal responses: expanding its in-house QA team (rejected due to Vietnamese senior QA engineer scarcity and 6-9 month time-to-hire), engaging a large multinational systems integrator (rejected due to cost and cultural fit), and delaying the 5G rollout schedule (rejected due to competitive market pressure from Vietnamese telecom peers).

Why Corpshore Vietnam

The client selected Corpshore Vietnam for three reasons: our locally-based team could work fully in Vietnamese with the client's internal teams without translation friction, the engagement could launch within four weeks of contract signature (versus 12+ weeks for a multinational SI), and our proposed engagement model bundled test automation infrastructure development with ongoing manual test execution, giving the client a durable QA capability rather than short-term surge capacity.

As a Vietnamese-operating client engaging a Vietnamese subsidiary of a multinational group, this case study is notable within our portfolio: it demonstrates the value of the Corpshore Vietnam local footprint for domestic clients, not just for international clients seeking Vietnam delivery.

The engagement

28 QA engineers in Ho Chi Minh City, all Vietnamese-speaking. Team composition: 18 test automation engineers (Selenium, Playwright, Robot Framework, and telecom-specific protocol testing with Postman, Wireshark, and SIP testing tools), 10 manual test specialists focused on user experience and integration scenarios. Team works fully onsite at Corpshore Vietnam's HCMC facility with a rotating pair of senior automation engineers embedded at the client's testing lab in HCMC during release peaks.

Approach and methodology

Test automation infrastructure buildout. Phase 1 focused on establishing the automation framework, CI/CD test triggers, and test result dashboards. Coverage rose from 34% at baseline to 62% by month three, achieving the automation-first test strategy the client had prioritized.

Regression suite hardening. Every production incident post-engagement start triggered a mandatory retrospective, root cause analysis, and addition of specific test cases preventing recurrence. This discipline is credited with reducing production defect leakage by 82% across the engagement.

Release cycle test window compression. Manual test cycles that had previously required 5-7 days pre-release were compressed to 1.5-2 days by automating the previously-manual regression suite and by parallelizing test execution across cloud test infrastructure.

Results

Test automation coverage rose from 34% to 93% by month six. Production defect leakage dropped by 82% across all severity levels. Release cadence increased from bi-weekly to weekly without quality regression. The 5G rollout completed to schedule with no repeat of Q4 2025's incident pattern. The client's CEO cited the improved QA capability in the annual shareholder letter.

The engagement continues into a second phase covering the client's business support systems modernization and customer-facing app development. The client has become a Corpshore Vietnam reference for Vietnamese enterprise IT engagements.

Enduring value

The test automation framework, CI/CD test triggers, and test result dashboards built during the engagement are the client's IP and continue to be used across their 5G, billing, and customer app releases. The client's internal QA team has been trained on the framework and now operates a hybrid model with Corpshore QA engineers embedded for specific release peaks.