I found it hard to find info on the Pharo Bootstrap, so I went looking to understand the it by identifying very first creation on disk of the smallest�� "seed".image�� file that will later become the final build artifact.�� I'm sharing here to have a record I can refer to later, and maybe others find interesting.Looking at the log from the latest build...Searching on "BUILD_NUMBER=" indicates the first major CI step is...+ BUILD_NUMBER=822 BOOTSTRAP_ARCH=32 bash ./bootstrap/scripts/2-download.sh�� [1] which downloads 24MB " bootstrapImage.zip" [2]which I presume is an almost full image to run the bootstrap process.The next major CI step is...+ BUILD_NUMBER=822 BOOTSTRAP_ARCH=32 bash ./bootstrap/scripts/3-prepare.sh�� [3] which uses the downloaded "Pharo.image" to (I presume) produce the seed "bootstrap.image" file.����(This is not indicated explicitly in the logs, but step 4 copies that filewith a shell command, so my presumption. It would be nice for this to be explicitly logged"prepare.sh executes two commands..../pharo Pharo.image ..../bootstrap/scripts/prepare_image.st --save --quit�� [4]which seems to modify the downloaded "Pharo.image",��not create bootstrap.image./pharo Pharo.image ..../bootstrap/scripts/bootstrap.st --ARCH=32 --BUILD_NUMBER=822 --quit�� ��[5]which does... "PBBootstrap fromCommandLine bootstrap"�� [6] [7]which does...�� �� PBBootstrap>>#bootstrap���� �� �� �� PBStepStartedSignal log: 'Starting�� Process.'.�� �� �� �� self prepareBootstrap.�� �� �� �� [self createImage ] on:AssertionFailure do: [ :e | e resume ].�� �� �� �� self initializeImage.�� �� �� �� PBStepFinishedSignal log: 'Process ended.'and digging a bit...�� �� PBBootstrap>>#createImage�� �� �� �� | builder |�� �� �� �� builder := PBImageBuilderSpur50 forArchitecture: architecture.�� �� �� �� builder definitionFetcher: versionFetcher.�� �� �� �� builder buildNumber: buildNumber.�� �� �� �� builder imageFileReference: imageReference.�� �� �� �� builder systemDefinition: ringEnvironment.�� �� �� �� builder espellBackend instanceVariableMapping: (PBInstanceVariableMapping onEnvironment: ringEnvironment ).�� �� �� �� builder bootstrap�� �� PBImageBuilderSpur50-class>>#forArchitecture: architecture �� �� �� �� | candidates |�� �� �� �� candidates := self subclasses select: [ :sc | sc name endsWith: architecture, 'bit' ].�� �� �� �� candidates���� �� �� �� �� �� ifEmpty: [ self error: 'No candidates for architecture: ', architecture ].�� �� �� �� candidates size > 1�� �� �� �� �� �� ifTrue: [ self error: 'More than one candidate for architecture: ', architecture ].�� �� �� �� ^ candidates anyOne new
�� �� PBImageBuilderSpur50 >>#initialize�� �� �� �� super initialize.�� �� �� �� statistics := PBBootstrapStatistics new.�� �� �� �� logger := PBBootstrapLogger new.�� �� �� �� imageFileReference := 'bootstrap.image' asFileReference.�� �� �� �� "the default espell backend for the bootstrap"�� �� �� �� self initializeBackend.�� ���� �� �� �� self instantiateClassLoader.��ahh, there is the reference to "bootstrap.image"So just to round out a high level overview, the last two messages sent are defined as...�� �� PBImageBuilderSpur5032bit>>#initializeBackend �� �� �� �� espellBackend := EPSimulatorBackend for32Bit forBootstrap�� ����which I won't dig further but the class seems available at��[8]and Espell is described briefly at [9] (but what is a "MOP"? the term is not defined there)�� �� PBImageBuilderSpur50>>#instantiateClassLoader �� �� �� �� classLoader := PBSpurClassLoader new.������which is defined at [10], and��there is an interesting example at [11].So now I guess that bootstrap.image has been generated?Just curious, what is the size of this file right now, before the next step?Perhaps an `ls -l` could echo this to the build log.The penultimate major CI step seems to then start adding packages to bootstrap.image...+ BUILD_NUMBER=822 BOOTSTRAP_ARCH=32 bash ./bootstrap/scripts/4-build.sh���� located at [12] and searching on "${VM}" is enlightening.Its help information says...Pharo Build Script�� ==================�� This script assumes the existence of a new uninitialized image. Then it proceeds to its initialization and \"growing\".�� * Step 1:�� �� - Initialize the image�� �� - output: core.image�� * Step 2:�� �� - Bootstrap Monticello local repositories�� �� - output: monticello_bootstrap.image and changes file�� * Step 3:�� �� - Load Monticello remote repositories�� �� - output: monticello.image and changes file�� * Step 4:�� �� - Load Metacello�� �� - output: metacello.image and changes file�� * Step 5:�� �� - Load the rest of the image using BaselineOfIDE�� �� - output: Pharo.image and changes fileUnfortunately those steps are labelled in the script,but the first action shown in the log is...�� �� cp bootstrap.image Pharo7.0-compiler-32bit-9912d7c.image�� Initializing Bootstraped Image�� �� pharo --headless Pharo7.0-compiler-32bit-9912d7c.image The final major CI step was a fair way past what I was interested in right now. ...+ BUILD_NUMBER=822 bash ../bootstrap/scripts/prepare_for_upload.sh cheers -ben