Clipper (the xBase compiler)

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Stands for: Nantucket's compiler for dBASE III programs, 1985 to CA-Clipper 5.3b in 1997

Nantucket's compiler for the dBASE III language, first released in 1985, which turned interpreted database programs into standalone DOS executables; millions of small-business applications were built in it before Computer Associates bought it in 1992, and its last release was CA-Clipper 5.3b in 1997.

Clipper is an xBase compiler that implements a variant of the xBase language: it was created as a replacement for Ashton-Tate's dBASE III, and its advantage was that a program could be compiled and executed on DOS as a standalone application rather than run inside the dBASE interpreter, the one major dBASE feature it never implemented being the interactive dot prompt. Nantucket Corporation, started in 1984 by Barry ReBell on the management side and Brian Russell on the technical side with Larry Heimendinger as president, shipped the first release, Winter '84, on 25 May 1985 and named the next ones for seasons, Summer '85, Winter '85, Autumn '86 and the Summer '87 of 21 December 1987 that became the long-lived standard, before Clipper 5.0 in 1990 and 5.01 in April 1991. Between 1985 and 1992 millions of Clipper applications were built, typically for small businesses, and for banks and insurers as front ends to the mainframe. In 1992 Computer Associates bought the company for 190 million dollars and renamed the product CA-Clipper; 5.2 came in 1993, 5.3 in 1995 and the final 5.3b on 20 May 1997. Under its new owner Clipper failed to move from DOS to Windows and almost no new commercial applications were written in it after 1995; Harbour, xHarbour, Xbase++ and FlagShip keep the language alive today.

What it was and why it won. Clipper, from Nantucket Corporation and later Computer Associates, started as a native-code compiler for dBASE III databases and later evolved. dBASE ran programs through its interpreter and needed the dBASE product on every machine; Clipper compiled the same language into a DOS executable that ran on its own, faster, without licence fees per seat, and without exposing the source. The one major dBASE feature it did not implement was the interactive dot prompt, which mattered less to the developer shipping an application than to the user exploring a table. In the years between 1985 and 1992 millions of Clipper applications were built, typically for small businesses dealing with client management and inventory; for many smaller businesses a Clipper application designed to their needs was their first experience of software development, and many applications for banking and insurance companies were developed where the system was too small for the mainframe or as a front end to one.

The language grew. As the product matured it added elements of C and Pascal, object-oriented programming and the code-block data type, which hybridised dBASE macros, string evaluation, with function pointers, becoming far more powerful than the original language; Nantucket's Aspen project later matured into the Windows native-code CA-Visual Objects compiler. The releases: Nantucket Clipper Winter '84 on 25 May 1985, Summer '85, Winter '85 on 29 January 1986, Autumn '86 on 31 October 1986, Summer '87 on 21 December 1987, 5.00 in 1990, 5.01 on 15 April 1991 and 5.01 Rev. 129 on 31 March 1992; then CA Clipper 5.20 on 15 February 1993 with 5.2a to 5.2e through February 1995, 5.30 on 26 June 1995, 5.3a on 20 May 1996 and 5.3b on 20 May 1997, the last. The November 1991 New York Times reported Nantucket's success in convincing Soviet developers that buying was preferable to pirating: 2,000 copies sold in the Soviet Union against 250,000 worldwide.

The company and the sale. Nantucket Corporation was started in 1984 by Barry ReBell, management, and Brian Russell, technical, with Larry Heimendinger as president. In 1992 the company was sold to Computer Associates for 190 million dollars and the product was renamed CA-Clipper. It was one of three sales within a year: Borland bought Ashton-Tate and its dBASE, Microsoft bought Fox Software and its FoxPro, and Computer Associates bought Nantucket, as the xBase market peaked.

Decline and afterlife. In the early 1990s, under new ownership, Clipper failed to transition from DOS to Windows, and as a result almost no new commercial applications were written in it after 1995. By then the classically trained programmer expected strong typing, which the original dBASE language lacked; Visual Objects added it optionally, and the four languages that took over, Visual Basic, Microsoft Access, Delphi and PowerBuilder, all provided it. The language itself is actively implemented and extended by others: Xbase++ from Alaska Software and FlagShip commercially, and Harbour and xHarbour as free GPL projects, portable to DOS, Windows, Linux, Unix and macOS with extended libraries. For the network engineer the relevance is practical: a Clipper application on a shared .dbf directory is the reason many NetWare and later Windows file shares existed, its record locking is why the share had to be a real file server, and some of those applications are still running in 2026 on Harbour. The dBASE entry carries the language's parent; the Nantucket, Ashton-Tate and Borland records on the industry timeline carry the companies.

Also known as: ca-clipper, nantucket clipper, clipper summer 87, clipper 5.2, harbour, xharbour, xbase++

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