Adaytum Software was a British company that developed and sold Adaytum Planning software. The product, written primarily in Dyalog APL and later including J components, connected Dyalog Ltd. with IPSA employees Morten Kromberg, Gitte Christensen, Roger Hui, and Eric Iverson during the 1990s; all but Iverson would eventually become employees at Dyalog.
While Adaytum was founded by Guy Haddleton in 1990, the product that became Adaytum Planning was initially developed by George Kunzle with the name Kunzle Planning Software (KPS). Kunzle collaborated with Morten Kromberg and Haddleton to make a Dyalog APL port of his FREGI software that ran on the IBM mainframe. Haddleton's company continued to develop the product with significant success, while Kromberg joined former IPSA colleague Gitte Christensen in the small consulting company Insight Systems, later to merge again with Adaytum.
Kromberg was CTO of Adaytum for a time, and he and Christensen asisted the company in porting Adaytum Planning from DOS to Windows. They also incorporated J into the product: because of Dyalog's fixed workspace size Adaytum used C to manage large arrays, but this code was replaced with J with the help of Eric Iverson and Roger Hui at Jsoftware. As part of the process Adaytum funded J's sparse array implementation. In 1999 Eric Iverson became CTO of Adaytum.
Following the burst of the 2000s dot-com bubble, Adaytum was unable to move forward with plans to go public on the NASDAQ. It was acquired by Cognos in 2003 for $160 million. Christensen and Kromberg, who had left the company on acquisition to continue as consultants, accepted an offer made in 2004 by Pete Donnelly to take over management of Dyalog Ltd.
- Peter Donnelly. "Dyalog APL: A Personal History".
- Conor Hoekstra and others. Gitte Christensen of Dyalog Ltd.. The Array Cast episode 12. 2021-10-16.
- Conor Hoekstra and others. Roger Hui (1953-2021). The Array Cast episode 13. 2021-10-30.
- Faust, Anne. Press Release - Iverson Software Inc. J forums. 1999-08-09.
- John Hagerty. "Cognos acquires Adaytum and bolsters performance management agenda". Computer Weekly. 2003-01-15