Cover image for case study on Sim Local’s eSIM platform, showing digital travel connectivity and telecom scalability with Sonalake’s engineering partnership.

Enabling Growth Through Engineering: Scaling Sim Local’s eSIM Sales Platform

The Market Shift: eSIMs Reshape Travel Connectivity

The telecom industry is undergoing a structural shift as physical SIM cards give way to embedded SIMs (eSIMs). For global travelers, eSIMs promise a frictionless, fully digital experience - no more queuing at kiosks or swapping plastic cards abroad. For providers like Sim Local, this evolution opened up new commercial opportunities - but also brought significant technical and operational challenges.

As one of the world’s leading SIM providers in the travel retail sector, Sim Local saw the potential of launching a travel eSIM offering. But capitalizing on that opportunity required building a modern digital sales platform - from concept to execution.

Screenshot of Sim Local’s eSIM product page for the United Kingdom, displaying various 30-day mobile data plans from providers like EE and Lycamobile. The page highlights pricing, plan details, promotional offers, and features such as 4G/5G speed, unlimited local SMS, and roaming support.

The Challenge

Sim Local was moving fast: the company had early product validation and growing demand from both consumers and global distribution partners. However, their engineering infrastructure needed a step change to support scale and deliver reliably.

They faced several interrelated challenges:

An evolving product vision with shifting technical requirements
A need to support rapid go-to-market delivery for the interim solution
A growing backlog of features and client integrations
The pressure of onboarding major partners while still establishing a strong internal tech foundation

Sim Local needed more than just additional developers - they needed an engineering partner to help shape the future of their tech stack and product delivery.

Our Role: From MVP to Sales Engine

Sonalake partnered with Sim Local at a pivotal time in their growth journey.

We began with a cross-functional team of Java and React engineers, focused initially on augmenting core product development capacity. But our role quickly expanded as we brought technical leadership and architectural direction to the engagement.

Phase 1: Enabling Speed with Flexibility

Sim Local needed to move fast, so the first goal was to design and build a flexible interim platform - a launchpad that could enable early market entry without overcommitting to a rigid architecture. We collaborated closely with their product and engineering leads to:

Define a modular MVP architecture
Build features for onboarding early partners and testing the eSIM proposition
Establish delivery processes that balanced velocity with stability

Phase 2: Engineering Maturity for Long-Term Scale

With proof points established, we helped architect and deliver a fully-fledged sales engine with a different underlying architecture, built to support:

Full B2C and B2B sales workflows
Scalability for international traffic and onboarding
Extensibility to support new partner integrations and product iterations

Along the way, Sonalake:

Ran a technical gap analysis to identify and address key risks
Set up a cross-company Design Authority Group to ensure alignment and governance
Embedded engineers across frontend, backend, and mobile teams
Fostered strong cultural alignment and shared delivery ownership

The Outcome

The collaboration between Sim Local and Sonalake delivered both immediate and strategic results:

A scalable, production-ready sales platform that supports Sim Local’s growing eSIM offering
Adoption of modern engineering practices and a more mature delivery approach
Resolution of key areas of technical debt and improvement of architectural foundations
Accelerated onboarding of new partners through a dedicated, high-performing team
Increased development velocity and improved overall product delivery capability

The Takeaway

Launching a modern digital product - especially in a fast-evolving space like eSIM travel - requires more than code. It requires adaptable architecture, embedded collaboration, and a partner who can grow with your vision.

Sonalake helped Sim Local navigate from MVP thinking to long-term product engineering. Together, we laid the groundwork for a scalable, competitive offering in the global travel connectivity market.

Testimonial

"Sonalake partnership empowered Sim Local’s tech team to adapt and scale with the market - driven by deep expertise, top talent, and on-time deliver"

Dejan Jug, CIO