Built payment reconciliation for solar PAYGO | Product Manager Case Study - Brian Chirchir
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Enterprise · IoT

Built payment reconciliation for solar PAYGO

Pay-as-you-go solar through M-PESA reconciliation

Product Owner on DayLipa, an M-PESA C2B reconciliation engine for PAYGO solar operators managing 5,000-plus connected devices where payment-device mismatches translated directly into customer trust failures.

Product Owner M-PESA C2B USSD

DayLipa is a strong portfolio case because it ties product judgment directly to system reliability and customer trust.

Challenge

PAYGO solar operators relied on near-real-time reconciliation between M-PESA payments and device activation. When reconciliation failed, families who had already paid could lose access to light, which created immediate support volume and long-term trust erosion.

Context

Solar PAYGO operators managing thousands of devices, plus field engineers troubleshooting payment mismatches in low-connectivity environments with feature phones.

Operating constraints

->M-PESA callbacks could be delayed, duplicated, or arrive out of order, so real-time assumptions were unsafe.

->Activation latency directly affected customer trust because paid households expected power to return within minutes.

->Most field engineers used feature phones, which ruled out native or mobile-web operational tooling.

->Operators needed self-serve business intelligence because lean engineering teams could not keep answering custom reporting requests.

Strategic approach

01

Designed for idempotent reconciliation with eventual consistency

Instead of forcing fragile real-time assumptions onto an unreliable callback pipeline, the reconciliation engine accepted duplicates and reorderings while converging safely within minutes.

02

Built the field flow around USSD

Observation showed the real device landscape in the field. USSD was the only interface every engineer could access, so troubleshooting workflows had to fit that constraint.

03

Specified the dashboard as a self-serve analytics layer

The dashboard was designed to answer regional, collections, and performance questions without creating a constant queue of engineering report requests.

My role

Served as Product Owner inside a cross-functional team at 4RDigital. Authored reconciliation documentation, specified the service engineering platform and USSD workflows, wrote the dashboard feature spec, and managed sprint and stakeholder alignment.

Results and impact

  • *Shipped an M-PESA C2B reconciliation approach that removed payment-device mismatch errors caused by duplicate or out-of-order callbacks.
  • *Specified a USSD-based field operations flow aligned with the actual feature-phone reality of service teams.
  • *Defined acceptance criteria for 12 dashboard views so operators could answer operational questions without engineering mediation.
  • *Reduced support risk by making the consistency model explicit for both engineers and operators.

Reflection

The product lesson here was that technical reliability and stakeholder understanding are inseparable. I had to explain the consistency model almost as carefully as I specified it, because trust depended on both the behavior and the shared mental model.