{"header":{"message":"ripped intro from the SCP paper and manualized it","description":null,"timestamp":"2008-12-01T23:20:42Z","authors":[{"email":"visser@acm.org","name":"Eelco Visser"}]},"hash":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC","authors":[],"deps":{"hashes":[["YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC","ripped intro from the SCP paper and manualized it"],["AA",null],["6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC","draft manual"],["QPXJVRYK76DGVBRQ6YRVFV6US5LROYOW2NQ6757BBWXPAUHFH2QQC","boilerplate, platform stuff"],["EWQC6EZVGD6ZO2FTHTUKAJKG35CCXSIEHDHZHR6ENK77B5UY6EFQC","general information"],["Y3UAIWOKCJCDRHQHOMIM3WYR4MBGYYLM4KA6OMUHDJRT6EDGIFVAC","general information"]],"deps":["6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC"],"known":["QPXJVRYK76DGVBRQ6YRVFV6US5LROYOW2NQ6757BBWXPAUHFH2QQC","EWQC6EZVGD6ZO2FTHTUKAJKG35CCXSIEHDHZHR6ENK77B5UY6EFQC","Y3UAIWOKCJCDRHQHOMIM3WYR4MBGYYLM4KA6OMUHDJRT6EDGIFVAC"]},"hunks":[{"Edit":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":32,"atom":{"NewVertex":{"up_context":[{"change":2,"pos":430}],"down_context":[{"change":2,"pos":430}],"flag":"BLOCK","start":0,"end":820,"inode":{"change":2,"pos":38}}},"contents":[{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:0"}},{"Add":{"text":"Hydra is a tool for continuous integration testing and software","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:64"}},{"Add":{"text":"release that uses a purely functional language to describe build jobs","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:134"}},{"Add":{"text":"and their dependencies. Continuous integration is a simple technique","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:204"}},{"Add":{"text":"to improve the quality of the software development process. An","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:268"}},{"Add":{"text":"automated system continuously or periodically checks out the source","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:336"}},{"Add":{"text":"code of a project, builds it, runs tests, and produces reports for the","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:407"}},{"Add":{"text":"developers. Thus, various errors that might accidentally be committed","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:478"}},{"Add":{"text":"into the code base are automatically caught. Such a system allows","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:545"}},{"Add":{"text":"more in-depth testing than what developers could feasibly do manually:","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:616"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:617"}},{"Add":{"text":"

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:622"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:623"}},{"Add":{"text":"

Portability testing: The software may need to be built","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:698"}},{"Add":{"text":" and tested on many different platforms. It is infeasible for each","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:767"}},{"Add":{"text":" developer to do this before every commit. ","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:812"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:819"}}]}},{"Replacement":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":52,"ins":{"up_context":[{"change":2,"pos":431}],"down_context":[{"change":2,"pos":504}],"flag":"BLOCK","start":821,"end":2210,"inode":{"change":2,"pos":38}},"del":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":431},"to":{"change":2,"start":431,"end":504},"introduced_by":2}],"inode":{"change":2,"pos":38}},"ins_contents":[{"Add":{"text":"
Likewise, many projects have very large test sets (e.g.,","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:882"}},{"Add":{"text":" regression tests in a compiler, or stress tests in a DBMS) that can","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:952"}},{"Add":{"text":" take hours or days to run to completion. ","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:996"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1003"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1004"}},{"Add":{"text":"
Many kinds of static and dynamic analyses can be performed as","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1071"}},{"Add":{"text":" part of the tests, such as code coverage runs and static analyses.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1140"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1147"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1148"}},{"Add":{"text":"
It may also be necessary to build many different variants","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1220"}},{"Add":{"text":" of the software. For instance, it may be necessary to verify that","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1289"}},{"Add":{"text":" the component builds with various versions of a compiler.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1349"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1356"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1357"}},{"Add":{"text":"
Developers typically use incremental building to test their","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1422"}},{"Add":{"text":" changes (since a full build may take too long), but this is","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1484"}},{"Add":{"text":" unreliable with many build management tools (such as Make), i.e.,","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1552"}},{"Add":{"text":" the result of the incremental build might differ from a full build.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1622"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1629"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1630"}},{"Add":{"text":"
It ensures that the software can be built from the sources under","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1700"}},{"Add":{"text":" revision control. Users of version management systems such as CVS","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1769"}},{"Add":{"text":" and Subversion often forget to place source files under revision","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1836"}},{"Add":{"text":" control.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1847"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1854"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1855"}},{"Add":{"text":"
The machines on which the continuous integration system runs","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1921"}},{"Add":{"text":" ideally provides a clean, well-defined build environment. If this","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:1990"}},{"Add":{"text":" environment is administered through proper SCM techniques, then","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2056"}},{"Add":{"text":" builds produced by the system can be reproduced. In contrast,","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2121"}},{"Add":{"text":" developer work environments are typically not under any kind of SCM","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2191"}},{"Add":{"text":" control.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2202"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2209"}}],"del_contents":[{"Del":{"text":"Hydra is a buildfarm system based on the Nix software deployment","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:495"}},{"Del":{"text":"system.","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:503"}}]}},{"Edit":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":86,"atom":{"NewVertex":{"up_context":[{"change":2,"pos":505}],"down_context":[{"change":2,"pos":505}],"flag":"BLOCK","start":2211,"end":3061,"inode":{"change":2,"pos":38}}},"contents":[{"Add":{"text":"
In large projects, developers often work on a particular","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2272"}},{"Add":{"text":" component of the project, and do not build and test the composition","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2342"}},{"Add":{"text":" of those components (again since this is likely to take too long).","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2411"}},{"Add":{"text":" To prevent the phenomenon of ``big bang integration'', where","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2474"}},{"Add":{"text":" components are only tested together near the end of the development","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2544"}},{"Add":{"text":" process, it is important to test components together as soon as","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2610"}},{"Add":{"text":" possible (hence continuous integration).","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2662"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2669"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2670"}},{"Add":{"text":"
It allows software to be released by automatically","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2735"}},{"Add":{"text":" creating packages that users can download and install. To do this","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2804"}},{"Add":{"text":" manually represents an often prohibitive amount of work, as one may","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2874"}},{"Add":{"text":" want to produce releases for many different platforms: e.g.,","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:2937"}},{"Add":{"text":" installers for Windows and Mac OS X, RPM or Debian packages for","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3003"}},{"Add":{"text":" certain Linux distributions, and so on.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3045"}},{"Add":{"text":"
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3052"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3053"}},{"Add":{"text":"

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3059"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3060"}}]}},{"Replacement":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":107,"ins":{"up_context":[{"change":2,"pos":511}],"down_context":[{"change":2,"pos":530}],"flag":"BLOCK","start":3062,"end":3616,"inode":{"change":2,"pos":38}},"del":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":511},"to":{"change":2,"start":511,"end":530},"introduced_by":2}],"inode":{"change":2,"pos":38}},"ins_contents":[{"Add":{"text":"In its simplest form, a continuous integration tool sits in a loop","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3128"}},{"Add":{"text":"building and releasing software components from a version management","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3197"}},{"Add":{"text":"system. For each component, it performs the following tasks:","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3259"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3260"}},{"Add":{"text":"

It obtains the latest version of the component's source code","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3331"}},{"Add":{"text":" from the version management system.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3369"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3370"}},{"Add":{"text":"
It runs the component's build process (which presumably includes","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3440"}},{"Add":{"text":" the execution of the component's test set).","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3486"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3487"}},{"Add":{"text":"
It presents the results of the build (such as error logs and","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3553"}},{"Add":{"text":" releases) to the developers, e.g., by producing a web page.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3615"}}],"del_contents":[{"Del":{"text":"... advantages ...","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:529"}}]}},{"Edit":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":122,"atom":{"NewVertex":{"up_context":[{"change":2,"pos":531}],"down_context":[{"change":2,"pos":531}],"flag":"BLOCK","start":3617,"end":3623,"inode":{"change":2,"pos":38}}},"contents":[{"Add":{"text":"

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3622"}}]}},{"Edit":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":125,"atom":{"NewVertex":{"up_context":[{"change":2,"pos":537}],"down_context":[{"change":2,"pos":537}],"flag":"BLOCK","start":3624,"end":3775,"inode":{"change":2,"pos":38}}},"contents":[{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3624"}},{"Add":{"text":"Examples of continuous integration tools include CruiseControl","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3687"}},{"Add":{"text":"Tinderbox, Sisyphus, Anthill and BuildBot. These tools have various","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3755"}},{"Add":{"text":"limitations.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3768"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3769"}},{"Add":{"text":"

They do not manage the build environment. The build","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3842"}},{"Add":{"text":"environment consists of the dependencies necessary to perform a build","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3912"}},{"Add":{"text":"action, e.g., compilers, libraries, etc. Setting up the environment","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:3981"}},{"Add":{"text":"is typically done manually, and without proper SCM control (so it may","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4051"}},{"Add":{"text":"be hard to reproduce a build at a later time). Manual management of","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4120"}},{"Add":{"text":"the environment scales poorly in the number of configurations that","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4187"}},{"Add":{"text":"must be supported. For instance, suppose that we want to build a","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4253"}},{"Add":{"text":"component that requires a certain compiler X. We then have to go to","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4322"}},{"Add":{"text":"each machine and install X. If we later need a newer version of X,","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4390"}},{"Add":{"text":"the process must be repeated all over again. An ever worse problem","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4458"}},{"Add":{"text":"occurs if there are conflicting, mutually exclusive versions of the","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4526"}},{"Add":{"text":"dependencies. Thus, simply installing the latest version is not an","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4594"}},{"Add":{"text":"option. Of course, we can install these components in different","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4659"}},{"Add":{"text":"directories and manually pass the appropriate paths to the build","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4724"}},{"Add":{"text":"processes of the various components. But this is a rather tiresome","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4792"}},{"Add":{"text":"and error-prone process.
","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4823"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4824"}},{"Add":{"text":"
They do not easily support variability in software","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4884"}},{"Add":{"text":"systems. A system may have a great deal of build-time","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:4944"}},{"Add":{"text":"variability: optional functionality, whether to build a debug or","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5009"}},{"Add":{"text":"production version, different versions of dependencies, and so on.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5076"}},{"Add":{"text":"(For instance, the Linux kernel now has over 2,600 build-time","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5138"}},{"Add":{"text":"configuration switches.) It is therefore important that a continuous","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5208"}},{"Add":{"text":"integration tool can easily select and test different instances from","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5277"}},{"Add":{"text":"the configuration space of the system to reveal problems, such as","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5343"}},{"Add":{"text":"erroneous interactions between features. In a continuous integration","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5413"}},{"Add":{"text":"setting, it is also useful to test different combinations of versions","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5483"}},{"Add":{"text":"of subsystems, e.g., the head revision of a component against stable","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5552"}},{"Add":{"text":"releases of its dependencies, and vice versa, as this can reveal","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5617"}},{"Add":{"text":"various integration problems.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5647"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5648"}},{"Add":{"text":"

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5654"}},{"Add":{"text":"","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5655"}}]}},{"Edit":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":167,"atom":{"NewVertex":{"up_context":[{"change":2,"pos":544}],"down_context":[{"change":2,"pos":544}],"flag":"BLOCK","start":5657,"end":6145,"inode":{"change":2,"pos":38}}},"contents":[{"Add":{"text":"Hydra, is a continuous integration tool that solves these","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5723"}},{"Add":{"text":"problems. It is built on top of the Nix","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5791"}},{"Add":{"text":"package manager, which has a purely functional language for","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5855"}},{"Add":{"text":"describing package build actions and their dependencies. This allows","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5925"}},{"Add":{"text":"the build environment for projects to be produced automatically and","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:5993"}},{"Add":{"text":"deterministically, and variability in components to be expressed","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6058"}},{"Add":{"text":"naturally using functions; and as such is an ideal fit for a","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6119"}},{"Add":{"text":"continuous build system.","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6144"}}]}},{"Edit":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":268,"atom":{"EdgeMap":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":2581},"to":{"change":2,"start":2581,"end":2608},"introduced_by":2}],"inode":{"change":2,"pos":38}}},"contents":[{"Del":{"text":"","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:2581"}},{"Del":{"text":"

","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:2586"}},{"Del":{"text":"","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:2587"}},{"Del":{"text":"Hydra on Windows??","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:2606"}},{"Del":{"text":"","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:2607"}}]}},{"Replacement":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":460,"ins":{"up_context":[{"change":2,"pos":7649}],"down_context":[{"change":2,"pos":7666}],"flag":"BLOCK","start":6146,"end":6168,"inode":{"change":2,"pos":38}},"del":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":7649},"to":{"change":2,"start":7649,"end":7666},"introduced_by":2}],"inode":{"change":2,"pos":38}},"ins_contents":[{"Add":{"text":"

3.2. Jobsets

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6167"}}],"del_contents":[{"Del":{"text":"

Jobsets

","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:7665"}}]}},{"Replacement":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":513,"ins":{"up_context":[{"change":2,"pos":8844}],"down_context":[{"change":2,"pos":8865}],"flag":"BLOCK","start":6169,"end":6195,"inode":{"change":2,"pos":38}},"del":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":8844},"to":{"change":2,"start":8844,"end":8865},"introduced_by":2}],"inode":{"change":2,"pos":38}},"ins_contents":[{"Add":{"text":"

3.2. Release Set

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6194"}}],"del_contents":[{"Del":{"text":"

Release Set

","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:8864"}}]}},{"Replacement":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":521,"ins":{"up_context":[{"change":2,"pos":8987}],"down_context":[{"change":2,"pos":9010}],"flag":"BLOCK","start":6196,"end":6224,"inode":{"change":2,"pos":38}},"del":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":8987},"to":{"change":2,"start":8987,"end":9010},"introduced_by":2}],"inode":{"change":2,"pos":38}},"ins_contents":[{"Add":{"text":"

3.3. Building Jobs

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6223"}}],"del_contents":[{"Del":{"text":"

Building Jobs

","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:9009"}}]}},{"Replacement":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":524,"ins":{"up_context":[{"change":2,"pos":9012}],"down_context":[{"change":2,"pos":9033}],"flag":"BLOCK","start":6225,"end":6251,"inode":{"change":2,"pos":38}},"del":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":9012},"to":{"change":2,"start":9012,"end":9033},"introduced_by":2}],"inode":{"change":2,"pos":38}},"ins_contents":[{"Add":{"text":"

3.4. release.nix

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6250"}}],"del_contents":[{"Del":{"text":"

release.nix

","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:9032"}}]}},{"Replacement":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":536,"ins":{"up_context":[{"change":2,"pos":9254}],"down_context":[{"change":2,"pos":9292}],"flag":"BLOCK","start":6252,"end":6295,"inode":{"change":2,"pos":38}},"del":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":9254},"to":{"change":2,"start":9254,"end":9292},"introduced_by":2}],"inode":{"change":2,"pos":38}},"ins_contents":[{"Add":{"text":"

3.5. Building on the command line

","pos":"YOC4WW2T4CGI4OV6BRFOEPTBURZSIU7JSRH3B7HAT5DVHV2IPQQQC:6294"}}],"del_contents":[{"Del":{"text":"

Building on the command line

","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:9291"}}]}},{"Edit":{"inode":{"change":2,"pos":38},"path":"doc/manual/manual.html","line":545,"atom":{"EdgeMap":{"edges":[{"previous":"BLOCK","flag":"BLOCK | DELETED","from":{"change":2,"pos":9520},"to":{"change":2,"start":9520,"end":9544},"introduced_by":2}],"inode":{"change":2,"pos":38}}},"contents":[{"Del":{"text":"

Release Set

","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:9540"}},{"Del":{"text":"","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:9541"}},{"Del":{"text":"","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:9542"}},{"Del":{"text":"","pos":"6A6CZ7SC2VGEGRC5LSNTDDM3LFWVYO6Z6QNDF74SBJWO5P6T3ARQC:9543"}}]}}],"owner":"grahamc","repo":"hydra","login":null}

…

Dependencies

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Review