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The development phase involves converting design specifications into executable programs. Effective development standards include requirements that programmers and other project participants discuss design specifications before programming begins. The procedures help ensure programmers clearly understand program designs and functional requirements.
Programmers use various techniques to develop computer programs. The large transaction-oriented programs associated with financial institutions have traditionally been developed using procedural programming techniques. Procedural programming involves the line-by-line scripting of logical instructions that are combined to form a program.
Primary procedural programming activities include the creation and testing of source code and the refinement and finalization of test plans. Typically, individual programmers write and review (desk test) program modules or components, which are small routines that perform a particular task within an application. Completed components are integrated with other components and reviewed, often by a group of programmers, to ensure the components properly interact. The process continues as component groups are progressively integrated and as interfaces between component groups and other systems are tested.
Advancements in programming techniques include the concept of "object-oriented programming." Object-oriented programming centers on the development of reusable program routines (modules) and the classification of data types (numbers, letters, dollars, etc.) and data structures (records, files, tables, etc.). Linking pre-scripted module objects to predefined data-class objects reduces development times and makes programs easier to modify. Refer to the "Software Development Techniques" section for additional information on object-oriented programming.
Organizations should complete testing plans during the development phase. Additionally, they should update conversion, implementation, and training plans and user, operator, and maintenance manuals.
Development Standards Development standards should be in place to address the responsibilities of application and system programmers. Application programmers are responsible for developing and maintaining end-user applications. System programmers are responsible for developing and maintaining internal and open-source operating system programs that link application programs to system software and subsequently to hardware. Managers should thoroughly understand development and production environments to ensure they appropriately assign programmer responsibilities.
Development standards should prohibit a programmer's access to data, programs, utilities, and systems outside their individual responsibilities. Library controls can be used to manage access to, and the movement of programs between, development, testing, and production environments. Management should also establish standards requiring programmers to document completed programs and test results thoroughly. Appropriate documentation enhances a programmer's ability to correct programming errors and modify production programs.
Coding standards, which address issues such as the selection of programming languages and tools, the layout or format of scripted code, and the naming conventions of code routines and program libraries, are outside the scope of this document. However, standardized, yet flexible, coding standards enhance an organization's ability to decrease coding defects and increase the security, reliability, and maintainability of application programs. Examiners should evaluate an organization's coding standards and related code review procedures.
Library Controls Libraries are collections of stored documentation, programs, and data. Program libraries include reusable program routines or modules stored in source or object code formats. Program libraries allow programmers to access frequently used routines and add them to programs without having to rewrite the code. Dynamic link libraries include executable code programs can automatically run as part of larger applications. Library controls should include:
Version Controls Library controls facilitate software version controls. Version controls provide a means to systematically retain chronological copies of revised programs and program documentation.
Development version control systems, sometimes referred to as concurrent version systems, assist organizations in tracking different versions of source code during development. The systems do not simply identify and store multiple versions of source code files. They maintain one file and identify and store only changed code. When a user requests a particular version, the system recreates that version. Concurrent version systems facilitate the quick identification of programming errors. For example, if programmers install a revised program on a test server and discover programming errors, they only have to review the changed code to identify the error.
Software Documentation Organizations should maintain detailed documentation for each application and application system in production. Thorough documentation enhances an organization's ability to understand functional, security, and control features and improves its ability to use and maintain the software. The documentation should contain detailed application descriptions, programming documentation, and operating instructions. Standards should be in place that identify the type and format of required documentation such as system narratives, flowcharts, and any special system coding, internal controls, or file layouts not identified within individual application documentation.
Management should maintain documentation for internally developed programs and externally acquired products. In the case of acquired software, management should ensure (either through an internal review or third-party certification) prior to purchase, that an acquired product's documentation meets their organization's minimum documentation standards. For additional information regarding acquired software distinctions (open/closed code) refer to the "Escrowed Documentation" discussion in the "Acquisition" section.
Examiners should consider access and change controls when assessing documentation activities. Change controls help ensure organizations appropriately approve, test, and record software modifications. Access controls help ensure individuals only have access to sections of documentation directly related to their job functions.
System documentation should include:
Application documentation should include: