consistent, & secure c. CREATE OUR SINGLE REPOSITORY OF TRUTH FOR THE ENTIRE SYSTEM i. ALL parts (code & environments) of the system are shared in a version control repository ii. Version control is for When a change causes the build or automated tests to fail: 1. No new work is allowed to enter the system until the problem is fixed. 2. Bring in whatever help is needed to resolve the problem iii. Prioritize tests of the integrated system as a whole 3. Work towards single-piece flow iii. Trunk & state of Deployment Pipeline represents & communicates the current state of the system iv. Modified Definition

the government context, Agile represents a good development approach when customizing an existing system or commercial off-the-shelf (COTS) product, or building a small-scale or self-constrained application into an existing operational baseline, system, or platform. Although it may not be the easiest approach, the government can also use Agile to build a large IT system from the ground up; however, in this the operational baseline. Several large acquisition programs, such as the Global Combat Support System-Joint (GCSS-J), have adopted Agile methods to build a future increment or block of capability.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389 29 Handling Operating System Variation 392CONTENTS vi 30 Environment Variables 393 30.1 File locations . . . . . . . . . . REPL formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401 30.8 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 402 30.9 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 672 43.13 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 675 43.14 Versioning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 388 29 Handling Operating System Variation 391CONTENTS vi 30 Environment Variables 392 30.1 File locations . . . . . . . . . . REPL formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 30.8 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 401 30.9 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 671 43.13 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674 43.14 Versioning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 388 29 Handling Operating System Variation 391CONTENTS vi 30 Environment Variables 392 30.1 File locations . . . . . . . . . . REPL formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 30.8 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 401 30.9 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 671 43.13 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674 43.14 Versioning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 29 Handling Operating System Variation 388CONTENTS vi 30 Environment Variables 389 30.1 File locations . . . . . . . . . . REPL formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396 30.7 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 397 30.8 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 645 42.13 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 648 42.14 Versioning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363 28 Handling Operating System Variation 366 29 Environment Variables 367 29.1 File locations . . . . . . . . . . . . . . . . formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373CONTENTS vi 29.7 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 374 29.8 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 591 41.12 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594 41.13 Versioning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363 28 Handling Operating System Variation 366 29 Environment Variables 367 29.1 File locations . . . . . . . . . . . . . . . . formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373CONTENTS vi 29.7 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 374 29.8 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 591 41.12 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594 41.13 Versioning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 29 Handling Operating System Variation 388CONTENTS vi 30 Environment Variables 389 30.1 File locations . . . . . . . . . . REPL formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396 30.7 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 397 30.8 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 645 42.13 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 648 42.14 Versioning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 29 Handling Operating System Variation 388CONTENTS vi 30 Environment Variables 389 30.1 File locations . . . . . . . . . . REPL formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396 30.7 System and Package Image Building . . . . . . . . . . . . . . . . . . . . . . . . . . 397 30.8 Debugging Missing Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 645 42.13 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 648 42.14 Versioning