SIM Expert

The Mid-Level SIM Engineer will work alongside the SIMs and Devices team to design, configure,

validate, and support SIM and eSIM solutions for multiple customer brands. The role combines hands-on

SIM profile engineering with Multi-IMSI behavior, OTA delivery, entitlement services, and ME enablement.

You will translate customer and network requirements into production-ready configurations, coordinate

with SIM and platform vendors, execute end-to-end testing, analyze failures, and maintain clear technical

documentation. The engineer should be comfortable taking ownership of a workstream while

collaborating closely on architecture and release decisions.

Must Have:

● 3–5 years of practical experience in SIM/eSIM engineering

● Practical understanding of Multi-IMSI solutions, IMSI selection and switching, network-selection

behavior, timers, fallback, prohibited PLMNs, and failure recovery.

● Experience creating and reviewing SIM/eSIM profile requirements and validating personalized

cards or downloadable profiles.

● Working knowledge of OTA architecture and operations, including APDU scripting, campaign

validation, secure channels and troubleshooting.

● Experience building structured test scenarios and analyzing APDU traces, modem/device logs,

PCAPs, and network registration failures.

● Familiarity with relevant ETSI, 3GPP, and GSMA specifications and the ability to convert

standards into implementable requirements and expected results.

● Clear written and spoken English, disciplined documentation, and confidence working directly

with vendors and cross-functional teams.

Strong Advantage:

● Direct experience with a commercial Multi-IMSI applet.

● Knowledge of GSMA TS.43 entitlement services.

● Android carrier enablement experience using AOSP.

● Experience supporting Apple carrier-bundle setup.

● Knowledge of SIM security and provisioning data, including Milenage, K/OPc, OTA keys,

transport keys, key exchange, and HSS dependencies.