People

Jonno Downes

Founder & Principal Consultant

Jonno is a payment solutions architect and technical leader with over 25 years of experience designing and delivering enterprise-scale platforms. He is equally comfortable defining target-state architectures for major banks as he is writing the code for high-performance lab projects.

Recent Selected Engagements:

• AP+ (Australian Payments Plus): Designed the fee billing and pricing solution for NPP, PayTo, and BPAY.
• AP+: Technical consultant for APRA CPS230 operational resilience compliance.
• eftpos Payments Australia: Led the end-to-end design for the national interchange fee settlement platform.
• AusPayNet: Technical lead for the industry-wide migration of AS2805/ISO8583 terminals to AES encryption.
• Commonwealth Bank: Senior Solutions Architect for major platform migrations (Project MeMo and PowerCARD).

Phil Herscovics

Co-Founder & Subject Matter Expert

Phil is a senior technical leader with over 30 years of payments systems experience. A specialist in high-availability, fault-tolerant switch systems and cloud-based "as a Service" infrastructure.

While currently holding a leadership role within a major Australian bank, Phil remains an active collaborator at Callendina. As a dedicated yacht racer, he serves as the primary subject matter expert and "chief laboratory tester" for the Ticktack project, ensuring our performance logistics tools meet the demands of real-world competition.