diff --git a/api/src/main/groovy/com/jessebrault/ssg/BuildScriptBasedStaticSiteGenerator.groovy b/api/src/main/groovy/com/jessebrault/ssg/BuildScriptBasedStaticSiteGenerator.groovy
index 639185d..0129973 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/BuildScriptBasedStaticSiteGenerator.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/BuildScriptBasedStaticSiteGenerator.groovy
@@ -2,8 +2,7 @@ package com.jessebrault.ssg
 
 import com.jessebrault.ssg.buildscript.Build
 import com.jessebrault.ssg.buildscript.BuildScriptConfiguratorFactory
-import com.jessebrault.ssg.buildscript.BuildScriptRunner
-import com.jessebrault.ssg.buildscript.BuildUtil
+import com.jessebrault.ssg.buildscript.FileBuildScriptGetter
 import com.jessebrault.ssg.util.Diagnostic
 import groovy.transform.EqualsAndHashCode
 import groovy.transform.NullCheck
@@ -50,7 +49,7 @@ final class BuildScriptBasedStaticSiteGenerator implements StaticSiteGenerator {
 
         if (this.buildScript == null) {
             logger.info('no specified build script; using defaults')
-            def result = BuildScriptRunner.runClosureScript { base ->
+            def result = FileBuildScriptGetter.runClosureScript { base ->
                 configuratorFactories.each {
                     it.get().accept(base)
                 }
@@ -58,9 +57,9 @@ final class BuildScriptBasedStaticSiteGenerator implements StaticSiteGenerator {
             this.builds.addAll(result)
         } else if (this.buildScript.exists() && this.buildScript.isFile()) {
             logger.info('running buildScript: {}', this.buildScript)
-            def buildScriptRunner = new BuildScriptRunner(this.buildScriptClassLoaderUrls)
+            def buildScriptRunner = new FileBuildScriptGetter(this.buildScriptClassLoaderUrls)
             this.buildScriptClassLoader = buildScriptRunner.getBuildScriptClassLoader()
-            def result = buildScriptRunner.runBuildScript(
+            def result = buildScriptRunner.getBuildInfo(
                     this.buildScript.name,
                     [args: buildScriptArgs]
             ) { base ->
diff --git a/api/src/main/groovy/com/jessebrault/ssg/SiteSpec.groovy b/api/src/main/groovy/com/jessebrault/ssg/SiteSpec.groovy
index 0e0c12b..04c068d 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/SiteSpec.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/SiteSpec.groovy
@@ -27,10 +27,6 @@ final class SiteSpec {
     final String name
     final String baseUrl
 
-    SiteSpec plus(SiteSpec other) {
-        concat(this, other)
-    }
-
     @Override
     String toString() {
         "SiteSpec(${ this.name }, ${ this.baseUrl })"
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/Build.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/Build.groovy
index fbd8d2c..4029737 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/Build.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/buildscript/Build.groovy
@@ -1,66 +1,44 @@
 package com.jessebrault.ssg.buildscript
 
-import com.jessebrault.ssg.SiteSpec
-import com.jessebrault.ssg.task.TaskFactory
-import com.jessebrault.ssg.task.TaskFactorySpec
+import com.jessebrault.ssg.model.Model
 import groovy.transform.EqualsAndHashCode
 import groovy.transform.NullCheck
-import groovy.transform.TupleConstructor
+import groowt.util.fp.property.Property
+import groowt.util.fp.provider.NamedProvider
+import groowt.util.fp.provider.NamedSetProvider
+import groowt.util.fp.provider.Provider
+import groowt.util.fp.provider.SetProvider
 
-import java.util.function.Function
+import static java.util.Objects.requireNonNull
 
-@TupleConstructor(defaults = false)
 @NullCheck(includeGenerated = true)
 @EqualsAndHashCode
 final class Build {
 
-    static Build getEmpty() {
-        new Build(
-                '',
-                OutputDirFunctions.DEFAULT,
-                SiteSpec.getBlank(),
-                [:],
-                [],
-                []
-        )
-    }
-
-    static Build get(Map<String, Object> args) {
-        new Build(
-                args.name as String ?: '',
-                args.outputDirFunction as Function<Build, OutputDir> ?: OutputDirFunctions.DEFAULT,
-                args.siteSpec as SiteSpec ?: SiteSpec.getBlank(),
-                args.globals as Map<String, Object> ?: [:],
-                args.taskFactorySpecs as Collection<TaskFactorySpec<TaskFactory>> ?: [],
-                args.includedBuilds as Collection<String> ?: []
-        )
-    }
-
-    static Build concat(Build b0, Build b1) {
-        new Build(
-                b0.name.blank ? b1.name : b0.name,
-                OutputDirFunctions.concat(b0.outputDirFunction, b1.outputDirFunction),
-                SiteSpec.concat(b0.siteSpec, b1.siteSpec),
-                b0.globals + b1.globals,
-                b0.taskFactorySpecs + b1.taskFactorySpecs,
-                b0.includedBuilds + b1.includedBuilds
-        )
-    }
-
-    final String name
-    final Function<Build, OutputDir> outputDirFunction
-    final SiteSpec siteSpec
-    final Map<String, Object> globals
-    final Collection<TaskFactorySpec<TaskFactory>> taskFactorySpecs
     final Collection<String> includedBuilds
+    final Property<String> name
+    final Property<String> siteName
+    final Property<String> baseUrl
+    final Provider<File> outputDir
+    final Provider<Map<String, Object>> globals
+    final Set<Provider<File>> textsDirs
+    final Set<NamedProvider<Model>> models
 
-    Build plus(Build other) {
-        concat(this, other)
+    @SuppressWarnings('GroovyAssignabilityCheck')
+    Build(Map args) {
+        this.includedBuilds = requireNonNull(args.includedBuilds)
+        this.name = requireNonNull(args.name)
+        this.siteName = requireNonNull(args.siteName)
+        this.baseUrl = requireNonNull(args.baseUrl)
+        this.outputDir = requireNonNull(args.outputDir)
+        this.globals = requireNonNull(args.globals)
+        this.textsDirs = requireNonNull(args.textsDirs)
+        this.models = requireNonNull(args.models)
     }
 
     @Override
     String toString() {
-        "Build(name: ${ this.name }, siteSpec: ${ this.siteSpec }, globals: ${ this.globals }, includedBuilds: ${ this.includedBuilds })"
+        "Build(name: ${ this.name })"
     }
 
 }
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildDelegateToBuildConverter.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildDelegateToBuildConverter.groovy
new file mode 100644
index 0000000..0e4e2b8
--- /dev/null
+++ b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildDelegateToBuildConverter.groovy
@@ -0,0 +1,51 @@
+package com.jessebrault.ssg.buildscript
+
+import com.jessebrault.ssg.buildscript.delegates.BuildDelegate
+import groovy.transform.NullCheck
+import groovy.transform.TupleConstructor
+
+@NullCheck
+@TupleConstructor(includeFields = true)
+class BuildDelegateToBuildConverter {
+
+    protected Build getFromDelegate(String name, BuildDelegate delegate) {
+        new Build(
+                name: name,
+                siteName: delegate.siteName,
+                baseUrl: delegate.baseUrl,
+                outputDir: delegate.outputDir,
+                globals: delegate.globals,
+                models: delegate.models
+        )
+    }
+
+    protected void getFromBuild(Build source) {
+        new BuildDelegate().tap {
+            siteName(source.siteName)
+            baseUrl(source.siteName)
+            outputDir(source.outputDir)
+            globals.set(source.globals)
+            textsDirs(source.textsDirs)
+            models(source.models)
+        }
+    }
+
+    private final FileBuildScriptGetter buildScriptGetter
+    private final File buildScriptsDir
+
+    Build convert(String name, BuildScriptBase buildScript) {
+        final BuildDelegate delegate
+        if (buildScript.extending != null) {
+            def extendingFrom = buildScriptGetter.getBuildInfo(buildScript.extending)
+            def build = this.convert(buildScript.extending, extendingFrom)
+            delegate = this.getFromBuild(build)
+        } else {
+            delegate = new BuildDelegate()
+        }
+        def cl = buildScript.buildClosure
+        cl.delegate = delegate
+        cl()
+        this.getFromDelegate(name, delegate)
+    }
+
+}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildGraph.java b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildGraph.java
deleted file mode 100644
index 0acf1d5..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildGraph.java
+++ /dev/null
@@ -1,73 +0,0 @@
-package com.jessebrault.ssg.buildscript;
-
-import com.jessebrault.ssg.util.Monoid;
-import org.jgrapht.Graph;
-import org.jgrapht.graph.DefaultEdge;
-import org.jgrapht.graph.DirectedAcyclicGraph;
-
-import java.util.Collection;
-import java.util.List;
-import java.util.function.BiFunction;
-
-public final class BuildGraph {
-
-    private static void addAncestorEdges(
-            Graph<BuildSpec, DefaultEdge> graph,
-            BuildSpec buildSpec,
-            Collection<BuildSpec> allBuildSpecs
-    ) {
-        if (!graph.containsVertex(buildSpec)) {
-            throw new IllegalStateException("Given buildSpec " + buildSpec.getName() + " is not in the given graph.");
-        }
-        for (final var extendingName : buildSpec.getExtending()) {
-            final var ancestor = allBuildSpecs.stream()
-                    .filter(bs -> extendingName.equals(bs.getName()))
-                    .findAny()
-                    .orElseThrow(() -> new IllegalStateException(
-                            "Could not find ancestor " + extendingName + " for buildSpec " + buildSpec.getName() + "."
-                    ));
-            graph.addEdge(ancestor, buildSpec);
-            addAncestorEdges(graph, ancestor, allBuildSpecs);
-        }
-    }
-
-    private final Graph<BuildSpec, DefaultEdge> graph;
-
-    public BuildGraph(Collection<BuildSpec> buildSpecs) {
-        this.graph = new DirectedAcyclicGraph<>(DefaultEdge.class);
-        for (final var buildSpec : buildSpecs) {
-            if (!this.graph.containsVertex(buildSpec)) {
-                this.graph.addVertex(buildSpec);
-            }
-            addAncestorEdges(this.graph, buildSpec, buildSpecs);
-        }
-    }
-
-    public List<BuildSpec> getParents(BuildSpec start) {
-        return this.graph.incomingEdgesOf(start).stream()
-                .map(this.graph::getEdgeSource)
-                .toList();
-    }
-
-    @Deprecated(forRemoval = true)
-    public BuildIntermediate toIntermediate(
-            BuildSpec rootSpec,
-            Monoid<BuildIntermediate> buildIntermediateMonoid,
-            BiFunction<BuildIntermediate, BuildSpec, BuildIntermediate> parentAndSpecToIntermediate
-    ) {
-        final List<BuildSpec> parents = this.getParents(rootSpec);
-        if (parents.size() == 0) {
-            return parentAndSpecToIntermediate.apply(buildIntermediateMonoid.getZero(), rootSpec);
-        } else {
-            final List<BuildIntermediate> parentIntermediates = parents.stream()
-                    .map(parent -> this.toIntermediate(parent, buildIntermediateMonoid, parentAndSpecToIntermediate))
-                    .toList();
-            final BuildIntermediate parentsReduced = parentIntermediates.stream()
-                    .reduce(buildIntermediateMonoid.getZero(), (bi0, bi1) ->
-                            buildIntermediateMonoid.getConcat().apply(bi0, bi1)
-                    );
-            return parentAndSpecToIntermediate.apply(parentsReduced, rootSpec);
-        }
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildIntermediate.java b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildIntermediate.java
deleted file mode 100644
index cbb1ae1..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildIntermediate.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.jessebrault.ssg.buildscript;
-
-import com.jessebrault.ssg.SiteSpec;
-import com.jessebrault.ssg.task.TaskFactory;
-import com.jessebrault.ssg.task.TaskFactorySpec;
-
-import java.util.Collection;
-import java.util.Map;
-import java.util.function.Function;
-
-public interface BuildIntermediate {
-    BuildSpec getBuildSpec();
-    Function<Build, OutputDir> getOutputDirFunction();
-    SiteSpec getSiteSpec();
-    Map<String, Object> getGlobals();
-    TypesContainer getTypes();
-    SourceProviders getSources();
-    Collection<TaskFactorySpec<TaskFactory>> getTaskFactorySpecs();
-    Collection<String> getIncludedBuilds();
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildMonoids.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildMonoids.groovy
deleted file mode 100644
index df933fe..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildMonoids.groovy
+++ /dev/null
@@ -1,48 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.SiteSpec
-import com.jessebrault.ssg.task.TaskFactory
-import com.jessebrault.ssg.task.TaskFactorySpec
-import com.jessebrault.ssg.util.Monoid
-import com.jessebrault.ssg.util.Monoids
-
-import java.util.function.Function
-
-final class BuildMonoids {
-
-    static final Monoid<Function<Build, OutputDir>> outputDirFunctionMonoid = OutputDirFunctions.DEFAULT_MONOID
-    static final Monoid<SiteSpec> siteSpecMonoid = SiteSpec.DEFAULT_MONOID
-    static final Monoid<Map<String, Object>> globalsMonoid = Monoids.getMapMonoid()
-    static final Monoid<TypesContainer> typesMonoid = TypesContainer.DEFAULT_MONOID
-    static final Monoid<SourceProviders> sourcesMonoid = SourceProviders.DEFAULT_MONOID
-
-    static final Monoid<Collection<TaskFactorySpec<TaskFactory>>> taskFactoriesMonoid =
-            Monoids.getMergeCollectionMonoid(
-                    TaskFactorySpec.SAME_NAME_AND_SUPPLIER_EQ,
-                    TaskFactorySpec.DEFAULT_SEMIGROUP
-            )
-
-    static final Monoid<Collection<String>> includedBuildsMonoid = Monoids.getCollectionMonoid()
-
-    static Monoid<BuildIntermediate> buildIntermediateMonoid = Monoids.of(SyntheticBuildIntermediate.getEmpty())
-            { bi0, bi1 ->
-                new SyntheticBuildIntermediate(
-                        BuildSpec.get(
-                                name: "SyntheticBuildSpec(${ bi0.buildSpec.name }, ${ bi1.buildSpec.name })",
-                                isAbstract: true,
-                                extending: [],
-                                buildClosure: { }
-                        ),
-                        outputDirFunctionMonoid.concat.apply(bi0.outputDirFunction, bi1.outputDirFunction),
-                        siteSpecMonoid.concat.apply(bi0.siteSpec, bi1.siteSpec),
-                        globalsMonoid.concat.apply(bi0.globals, bi1.globals),
-                        typesMonoid.concat.apply(bi0.types, bi1.types),
-                        sourcesMonoid.concat.apply(bi0.sources, bi1.sources),
-                        taskFactoriesMonoid.concat.apply(bi0.taskFactorySpecs, bi1.taskFactorySpecs),
-                        includedBuildsMonoid.concat.apply(bi0.includedBuilds, bi1.includedBuilds)
-                )
-            }
-
-    private BuildMonoids() {}
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptBase.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptBase.groovy
index cee595e..e76e1e1 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptBase.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptBase.groovy
@@ -1,7 +1,8 @@
 package com.jessebrault.ssg.buildscript
 
 import com.jessebrault.ssg.buildscript.delegates.BuildDelegate
-import groovy.transform.PackageScope
+import org.jetbrains.annotations.ApiStatus
+import org.jetbrains.annotations.Nullable
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 import org.slf4j.Marker
@@ -9,70 +10,47 @@ import org.slf4j.MarkerFactory
 
 import static java.util.Objects.requireNonNull
 
+@SuppressWarnings('unused')
 abstract class BuildScriptBase extends Script {
 
-    protected static final Logger logger = LoggerFactory.getLogger(BuildScriptBase)
-    protected static final Marker enter = MarkerFactory.getMarker('ENTER')
-    protected static final Marker exit = MarkerFactory.getMarker('EXIT')
+    static final Logger logger = LoggerFactory.getLogger(BuildScriptBase)
+    static final Marker enter = MarkerFactory.getMarker('ENTER')
+    static final Marker exit = MarkerFactory.getMarker('EXIT')
 
-    private static Collection<String> convertExtendingArg(Object arg) {
-        arg instanceof Collection<String> ? arg as Collection<String>
-                : arg instanceof String ? [arg] as Collection<String> : []
+    private String extending
+    private Closure buildClosure
+    private File projectRoot
+
+    File getProjectRoot() {
+        requireNonNull(this.projectRoot)
     }
 
-    protected final Collection<BuildSpec> buildSpecs = []
-
-    /**
-     * args keys and values:
-     * <ul>
-     *     <li><code>name: String<code></li>
-     *     <li><code>extending?: String | Collection&lt;String&gt;</code></li>
-     * </ul>
-     *
-     * @param args
-     * @param buildClosure
-     */
-    void abstractBuild(
-            Map<String, Object> args,
-            @DelegatesTo(value = BuildDelegate, strategy = Closure.DELEGATE_FIRST)
-            Closure<?> buildClosure
-    ) {
-        final Collection<String> extending = convertExtendingArg(args.extending)
-        this.buildSpecs << BuildSpec.get(
-                name: requireNonNull(args.name as String),
-                isAbstract:  true,
-                extending:  extending,
-                buildClosure: buildClosure
-        )
+    void setProjectRoot(File projectRoot) {
+        this.projectRoot = requireNonNull(projectRoot)
     }
 
-    /**
-     * args keys and values:
-     * <ul>
-     *     <li><code>name: String<code></li>
-     *     <li><code>extending?: String | Collection&lt;String&gt;</code></li>
-     * </ul>
-     *
-     * @param args
-     * @param buildClosure
-     */
-    void build(
-            Map<String, Object> args,
-            @DelegatesTo(value = BuildDelegate, strategy = Closure.DELEGATE_FIRST)
-            Closure<?> buildClosure
-    ) {
-        final Collection<String> extending = convertExtendingArg(args.extending)
-        this.buildSpecs << BuildSpec.get(
-                name: requireNonNull(args.name as String),
-                isAbstract:  false,
-                extending:  extending,
-                buildClosure: buildClosure
-        )
+    File file(String name) {
+        new File(this.projectRoot, name)
     }
 
-    @PackageScope
-    Collection<BuildSpec> getBuildSpecs() {
-        this.buildSpecs
+    void build(@Nullable String extending, @DelegatesTo(value = BuildDelegate) Closure buildClosure) {
+        this.extending = extending
+        this.buildClosure = buildClosure
+    }
+
+    void build(@DelegatesTo(value = BuildDelegate) Closure buildClosure) {
+        this.extending = null
+        this.buildClosure = buildClosure
+    }
+
+    @ApiStatus.Internal
+    @Nullable String getExtending() {
+        this.extending
+    }
+
+    @ApiStatus.Internal
+    Closure getBuildClosure() {
+        this.buildClosure
     }
 
 }
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptConfiguratorFactory.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptConfiguratorFactory.groovy
deleted file mode 100644
index 72029d4..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptConfiguratorFactory.groovy
+++ /dev/null
@@ -1,7 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import java.util.function.Consumer
-
-interface BuildScriptConfiguratorFactory {
-    Consumer<BuildScriptBase> get()
-}
\ No newline at end of file
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptRunner.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptRunner.groovy
deleted file mode 100644
index 0109b7d..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildScriptRunner.groovy
+++ /dev/null
@@ -1,77 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.util.ExtensionUtil
-import groovy.transform.NullCheck
-import groovy.transform.stc.ClosureParams
-import groovy.transform.stc.SimpleType
-import org.codehaus.groovy.control.CompilerConfiguration
-import org.slf4j.Logger
-import org.slf4j.LoggerFactory
-import org.slf4j.Marker
-import org.slf4j.MarkerFactory
-
-import java.util.function.Consumer
-
-@NullCheck
-final class BuildScriptRunner {
-
-    private static final Logger logger = LoggerFactory.getLogger(BuildScriptRunner)
-    private static final Marker enter = MarkerFactory.getMarker('ENTER')
-    private static final Marker exit = MarkerFactory.getMarker('EXIT')
-
-    private static Collection<Build> runBase(BuildScriptBase base) {
-        base.run()
-        BuildSpecUtil.getBuilds(base.getBuildSpecs())
-    }
-
-    static Collection<Build> runClosureScript(
-            @DelegatesTo(value = BuildScriptBase, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(value = SimpleType, options = 'com.jessebrault.ssg.buildscript.BuildScriptBase')
-            Closure<?> scriptBody
-    ) {
-        def base = new BuildScriptBase() {
-
-            @Override
-            Object run() {
-                scriptBody.delegate = this
-                scriptBody.resolveStrategy = Closure.DELEGATE_FIRST
-                scriptBody.call(this)
-            }
-
-        }
-        runBase(base)
-    }
-
-    private final GroovyClassLoader buildScriptClassLoader
-
-    BuildScriptRunner(Collection<URL> classLoaderUrls) {
-        this.buildScriptClassLoader = new GroovyClassLoader(
-                Thread.currentThread().contextClassLoader,
-                new CompilerConfiguration().tap {
-                    scriptBaseClass = BuildScriptBase.name
-                }
-        )
-        classLoaderUrls.each(this.buildScriptClassLoader::addURL)
-    }
-
-    GroovyClassLoader getBuildScriptClassLoader() {
-        this.buildScriptClassLoader
-    }
-
-    Collection<Build> runBuildScript(
-            String scriptName,
-            Map<String, Object> binding,
-            Consumer<BuildScriptBase> configureBuildScript
-    ) {
-        logger.trace(enter, 'scriptName: {}, binding: {}', scriptName, binding)
-        Class<?> scriptClass = this.buildScriptClassLoader.loadClass(ExtensionUtil.stripExtension(scriptName))
-        def scriptObject = scriptClass.getConstructor().newInstance()
-        assert scriptObject instanceof BuildScriptBase
-        scriptObject.setBinding(new Binding(binding))
-        configureBuildScript.accept(scriptObject)
-        def result = runBase(scriptObject)
-        logger.trace(exit, 'result: {}', result)
-        result
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildSpec.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildSpec.groovy
deleted file mode 100644
index 94d5bb5..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildSpec.groovy
+++ /dev/null
@@ -1,57 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.buildscript.delegates.BuildDelegate
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-
-@NullCheck
-@EqualsAndHashCode(excludes = 'buildClosure')
-final class BuildSpec {
-
-    static BuildSpec getEmpty() {
-        new BuildSpec('', false, [], { })
-    }
-
-    static BuildSpec get(Map<String, Object> args) {
-        new BuildSpec(
-                args.name as String ?: '',
-                args.isAbstract as boolean ?: false,
-                args.extending as Collection<String> ?: [],
-                args.buildClosure as Closure<?> ?: { }
-        )
-    }
-
-    static BuildSpec get(
-            String name,
-            boolean isAbstract,
-            Collection<String> extending,
-            @DelegatesTo(value = BuildDelegate, strategy = Closure.DELEGATE_FIRST)
-            Closure<?> buildClosure
-    ) {
-        new BuildSpec(name, isAbstract, extending, buildClosure)
-    }
-
-    final String name
-    final boolean isAbstract
-    final Collection<String> extending
-    final Closure<?> buildClosure
-
-    private BuildSpec(
-            String name,
-            boolean isAbstract,
-            Collection<String> extending,
-            @DelegatesTo(value = BuildDelegate, strategy = Closure.DELEGATE_FIRST)
-            Closure<?> buildClosure
-    ) {
-        this.name = name
-        this.isAbstract = isAbstract
-        this.extending = extending
-        this.buildClosure = buildClosure
-    }
-
-    @Override
-    String toString() {
-        "BuildSpec(name: ${ this.name }, isAbstract: ${ this.isAbstract }, extending: ${ this.extending })"
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildSpecUtil.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildSpecUtil.groovy
deleted file mode 100644
index 2543a4c..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildSpecUtil.groovy
+++ /dev/null
@@ -1,90 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.buildscript.delegates.BuildDelegate
-import com.jessebrault.ssg.util.Monoid
-import groovy.transform.NullCheck
-import org.slf4j.Logger
-import org.slf4j.LoggerFactory
-import org.slf4j.Marker
-import org.slf4j.MarkerFactory
-
-import java.util.function.BiFunction
-
-@NullCheck
-final class BuildSpecUtil {
-
-    private static final Logger logger = LoggerFactory.getLogger(BuildSpecUtil)
-    private static final Marker enter = MarkerFactory.getMarker('ENTER')
-    private static final Marker exit = MarkerFactory.getMarker('EXIT')
-
-    private static Build intermediateToBuild(BuildIntermediate intermediate) {
-        Build.get(
-                name: intermediate.buildSpec.name,
-                outputDirFunction: intermediate.outputDirFunction,
-                siteSpec: intermediate.siteSpec,
-                globals: intermediate.globals,
-                taskFactorySpecs: intermediate.taskFactorySpecs,
-                includedBuilds: intermediate.includedBuilds
-        )
-    }
-
-    private static BuildIntermediate specToIntermediate(BuildSpec buildSpec, BuildIntermediate parent) {
-        def d = new BuildDelegate()
-        buildSpec.buildClosure.delegate = d
-        buildSpec.buildClosure.resolveStrategy = Closure.DELEGATE_FIRST
-        buildSpec.buildClosure()
-        new BuildDelegate.BuildDelegateBuildIntermediate(
-                buildSpec,
-                d,
-                parent,
-                BuildMonoids.siteSpecMonoid,
-                BuildMonoids.globalsMonoid,
-                BuildMonoids.typesMonoid,
-                BuildMonoids.sourcesMonoid,
-                BuildMonoids.taskFactoriesMonoid,
-                BuildMonoids.includedBuildsMonoid
-        )
-    }
-
-    private static BuildIntermediate reduceWithParents(
-            BuildSpec rootSpec,
-            BuildGraph buildGraph,
-            Monoid<BuildIntermediate> buildIntermediateMonoid,
-            BiFunction<BuildIntermediate, BuildSpec, BuildIntermediate> parentAndSpecToIntermediate
-    ) {
-        final List<BuildSpec> parents = buildGraph.getParents(rootSpec)
-        if (parents.size() == 0) {
-            parentAndSpecToIntermediate.apply(buildIntermediateMonoid.zero, rootSpec)
-        } else {
-            final List<BuildIntermediate> parentIntermediates = parents.collect {
-                reduceWithParents(it, buildGraph, buildIntermediateMonoid, parentAndSpecToIntermediate)
-            }
-            final BuildIntermediate parentsReduced = parentIntermediates.inject(buildIntermediateMonoid.zero)
-                    { acc, bi ->
-                        buildIntermediateMonoid.concat.apply(acc, bi)
-                    }
-            parentAndSpecToIntermediate.apply(parentsReduced, rootSpec)
-        }
-    }
-
-    static Collection<Build> getBuilds(Collection<BuildSpec> buildSpecs) {
-        logger.trace(enter, 'buildSpecs: {}', buildSpecs)
-        def graph = new BuildGraph(buildSpecs)
-        def intermediates = buildSpecs.findResults {
-            if (it.isAbstract) {
-                null
-            } else {
-                reduceWithParents(it, graph, BuildMonoids.buildIntermediateMonoid)
-                        { parent, spec ->
-                            specToIntermediate(spec, parent)
-                        }
-            }
-        }
-        def builds = intermediates.collect { intermediateToBuild(it) }
-        logger.trace(exit, 'builds: {}', builds)
-        builds
-    }
-
-    private BuildSpecUtil() {}
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildUtil.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildUtil.groovy
deleted file mode 100644
index ea026cd..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/BuildUtil.groovy
+++ /dev/null
@@ -1,24 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.util.Diagnostic
-
-final class BuildUtil {
-
-    static Collection<Diagnostic> diagnoseIncludedBuilds(Collection<Build> allBuilds) {
-        allBuilds.inject([] as Collection<Diagnostic>) { allDiagnostics, build ->
-            allDiagnostics + build.includedBuilds.inject([] as Collection<Diagnostic>) { buildDiagnostics, includedBuildName ->
-                def includedBuild = allBuilds.find { it.name == includedBuildName }
-                if (includedBuild == null) {
-                    buildDiagnostics + new Diagnostic(
-                            "The includedBuild ${ includedBuildName } is not in the collection of allBuilds"
-                    )
-                } else {
-                    buildDiagnostics
-                }
-            }
-        }
-    }
-
-    private BuildUtil() {}
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/DefaultBuildScriptConfiguratorFactory.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/DefaultBuildScriptConfiguratorFactory.groovy
deleted file mode 100644
index 23cae26..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/DefaultBuildScriptConfiguratorFactory.groovy
+++ /dev/null
@@ -1,71 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.html.PageToHtmlSpecProviders
-import com.jessebrault.ssg.html.PageToHtmlTaskFactory
-import com.jessebrault.ssg.html.TextToHtmlSpecProviders
-import com.jessebrault.ssg.html.TextToHtmlTaskFactory
-import com.jessebrault.ssg.page.PageTypes
-import com.jessebrault.ssg.page.PagesProviders
-import com.jessebrault.ssg.part.PartTypes
-import com.jessebrault.ssg.part.PartsProviders
-import com.jessebrault.ssg.template.TemplateTypes
-import com.jessebrault.ssg.template.TemplatesProviders
-import com.jessebrault.ssg.text.TextTypes
-import com.jessebrault.ssg.text.TextsProviders
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-import groovy.transform.TupleConstructor
-
-import java.util.function.Consumer
-import java.util.function.Supplier
-
-@TupleConstructor(includeFields = true, defaults = false)
-@NullCheck(includeGenerated = true)
-@EqualsAndHashCode(includeFields = true)
-final class DefaultBuildScriptConfiguratorFactory implements BuildScriptConfiguratorFactory {
-
-    private final File baseDir
-    private final Supplier<ClassLoader> classLoaderSupplier
-
-    @Override
-    Consumer<BuildScriptBase> get() {
-        return {
-            it.build(name: 'default') {
-                outputDirFunction = { Build build ->
-                    new OutputDir(new File(this.baseDir, build.name == 'default' ? 'build' : build.name))
-                }
-
-                types {
-                    textTypes << TextTypes.MARKDOWN
-                    pageTypes << PageTypes.getGsp(['.gsp', '.ssg.gst'], this.classLoaderSupplier.get())
-                    templateTypes << TemplateTypes.getGsp(['.gsp', '.ssg.gst'], this.classLoaderSupplier.get())
-                    partTypes << PartTypes.getGsp(['.gsp', '.ssg.gst'], this.classLoaderSupplier.get())
-                }
-
-                sources { base, types ->
-                    texts TextsProviders.from(new File(this.baseDir, 'texts'), types.textTypes)
-                    pages PagesProviders.from(new File(this.baseDir, 'pages'), types.pageTypes)
-                    templates TemplatesProviders.from(new File(this.baseDir, 'templates'), types.templateTypes)
-                    parts PartsProviders.from(new File(this.baseDir, 'parts'), types.partTypes)
-                }
-
-                taskFactories { base, sources ->
-                    register('textToHtml', TextToHtmlTaskFactory::new) {
-                        it.specsProvider += TextToHtmlSpecProviders.from(sources)
-                        it.allTextsProvider += sources.textsProvider
-                        it.allPartsProvider += sources.partsProvider
-                        it.allModelsProvider += sources.modelsProvider
-                    }
-
-                    register('pageToHtml', PageToHtmlTaskFactory::new) {
-                        it.specsProvider += PageToHtmlSpecProviders.from(sources.pagesProvider)
-                        it.allTextsProvider += sources.textsProvider
-                        it.allPartsProvider += sources.partsProvider
-                        it.allModelsProvider += sources.modelsProvider
-                    }
-                }
-            }
-        }
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/FileBuildScriptGetter.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/FileBuildScriptGetter.groovy
new file mode 100644
index 0000000..bc88b4d
--- /dev/null
+++ b/api/src/main/groovy/com/jessebrault/ssg/buildscript/FileBuildScriptGetter.groovy
@@ -0,0 +1,20 @@
+package com.jessebrault.ssg.buildscript
+
+import groovy.transform.NullCheck
+import groovy.transform.TupleConstructor
+
+@NullCheck
+@TupleConstructor(includeFields = true)
+final class FileBuildScriptGetter {
+
+    private final File projectRoot
+    private final GroovyClassLoader gcl
+
+    BuildScriptBase getBuildInfo(String name) {
+        Class<?> scriptClass = this.gcl.loadClass(name, true, false)
+        def scriptObject = scriptClass.getConstructor().newInstance()
+        assert scriptObject instanceof BuildScriptBase
+        scriptObject
+    }
+
+}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/OutputDir.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/OutputDir.groovy
deleted file mode 100644
index 40a7917..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/OutputDir.groovy
+++ /dev/null
@@ -1,41 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-
-@NullCheck
-@EqualsAndHashCode
-final class OutputDir {
-
-    private final String path
-
-    OutputDir(String path) {
-        this.path = path
-    }
-
-    OutputDir(File file) {
-        this(file.path)
-    }
-
-    File asFile() {
-        new File(this.path)
-    }
-
-    String asString() {
-        this.path
-    }
-
-    Object asType(Class<?> clazz) {
-        switch (clazz) {
-            case File -> this.asFile()
-            case String -> this.asString()
-            default -> throw new IllegalArgumentException('cannot cast to a class other than File or String')
-        }
-    }
-
-    @Override
-    String toString() {
-        "OutputDir(path: ${ this.path })"
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/OutputDirFunctions.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/OutputDirFunctions.groovy
deleted file mode 100644
index f6e33ba..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/OutputDirFunctions.groovy
+++ /dev/null
@@ -1,31 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.util.Monoid
-import com.jessebrault.ssg.util.Monoids
-
-import java.util.function.Function
-
-final class OutputDirFunctions {
-
-    static final Function<Build, OutputDir> DEFAULT = { Build build -> new OutputDir(build.name) }
-
-    static final Monoid<Function<Build, OutputDir>> DEFAULT_MONOID = Monoids.of(DEFAULT, OutputDirFunctions::concat)
-
-    static Function<Build, OutputDir> concat(
-            Function<Build, OutputDir> f0,
-            Function<Build, OutputDir> f1
-    ) {
-        f0 == OutputDirFunctions.DEFAULT ? f1 : f0
-    }
-
-    static Function<Build, OutputDir> of(File dir) {
-        return { new OutputDir(dir) }
-    }
-
-    static Function<Build, OutputDir> of(String path) {
-        return { new OutputDir(path) }
-    }
-
-    private OutputDirFunctions() {}
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/SourceProviders.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/SourceProviders.groovy
deleted file mode 100644
index 9c85e65..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/SourceProviders.groovy
+++ /dev/null
@@ -1,107 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.model.Model
-import com.jessebrault.ssg.page.Page
-import com.jessebrault.ssg.part.Part
-import com.jessebrault.ssg.provider.CollectionProvider
-import com.jessebrault.ssg.provider.CollectionProviders
-import com.jessebrault.ssg.template.Template
-import com.jessebrault.ssg.text.Text
-import com.jessebrault.ssg.util.Monoid
-import com.jessebrault.ssg.util.Monoids
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-import groovy.transform.TupleConstructor
-
-@NullCheck
-@EqualsAndHashCode
-final class SourceProviders {
-
-    static final Monoid<SourceProviders> DEFAULT_MONOID = Monoids.of(getEmpty(), SourceProviders::concat)
-
-    static SourceProviders concat(SourceProviders sp0, SourceProviders sp1) {
-        new SourceProviders(
-                sp0.textsProvider + sp1.textsProvider,
-                sp0.modelsProvider + sp1.modelsProvider,
-                sp0.pagesProvider + sp1.pagesProvider,
-                sp0.templatesProvider + sp1.templatesProvider,
-                sp0.partsProvider + sp1.partsProvider,
-                sp0.custom + sp1.custom
-        )
-    }
-
-    static SourceProviders get(Map<String, Object> args) {
-        new SourceProviders(
-                args.textsProvider as CollectionProvider<Text>
-                        ?: CollectionProviders.getEmpty() as CollectionProvider<Text>,
-                args.modelsProvider as CollectionProvider<Model<Object>>
-                        ?: CollectionProviders.getEmpty() as CollectionProvider<Model<Object>>,
-                args.pagesProvider as CollectionProvider<Page>
-                        ?: CollectionProviders.getEmpty() as CollectionProvider<Page>,
-                args.templatesProvider as CollectionProvider<Template>
-                        ?: CollectionProviders.getEmpty() as CollectionProvider<Template>,
-                args.partsProvider as CollectionProvider<Part>
-                        ?: CollectionProviders.getEmpty() as CollectionProvider<Part>,
-                args.custom as Map<String, CollectionProvider<?>> ?: [:]
-        )
-    }
-
-    static SourceProviders getEmpty() {
-        new SourceProviders(
-                CollectionProviders.getEmpty(),
-                CollectionProviders.getEmpty(),
-                CollectionProviders.getEmpty(),
-                CollectionProviders.getEmpty(),
-                CollectionProviders.getEmpty(),
-                [:]
-        )
-    }
-
-    final CollectionProvider<Text> textsProvider
-    final CollectionProvider<Model<Object>> modelsProvider
-    final CollectionProvider<Page> pagesProvider
-    final CollectionProvider<Template> templatesProvider
-    final CollectionProvider<Part> partsProvider
-
-    private final Map<String, CollectionProvider<Object>> custom
-
-    SourceProviders(
-            CollectionProvider<Text> textsProvider,
-            CollectionProvider<Model<Object>> modelsProvider,
-            CollectionProvider<Page> pagesProvider,
-            CollectionProvider<Template> templatesProvider,
-            CollectionProvider<Part> partsProvider,
-            Map<String, CollectionProvider<Object>> custom
-    ) {
-        this.textsProvider = textsProvider
-        this.modelsProvider = modelsProvider
-        this.pagesProvider = pagesProvider
-        this.templatesProvider = templatesProvider
-        this.partsProvider = partsProvider
-        this.custom = custom
-    }
-
-    SourceProviders plus(SourceProviders other) {
-        concat(this, other)
-    }
-
-    def <T> CollectionProvider<T> getCustom(String name, Class<T> tClass) {
-        this.custom.get(name) as CollectionProvider<T>
-    }
-
-    void putCustom(String name, CollectionProvider<?> customProvider) {
-        this.custom.put(name, customProvider as CollectionProvider<Object>)
-    }
-
-    Map<String, CollectionProvider<Object>> getAllCustom() {
-        this.custom
-    }
-
-    @Override
-    String toString() {
-        "SourceProviders(textsProvider: ${ this.textsProvider }, modelsProvider: ${ this.modelsProvider }, " +
-                "pagesProvider: ${ this.pagesProvider }, templatesProvider: ${ this.templatesProvider }, " +
-                "partsProvider: ${ this.partsProvider })"
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/SyntheticBuildIntermediate.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/SyntheticBuildIntermediate.groovy
deleted file mode 100644
index ed77a60..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/SyntheticBuildIntermediate.groovy
+++ /dev/null
@@ -1,74 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.SiteSpec
-import com.jessebrault.ssg.task.TaskFactory
-import com.jessebrault.ssg.task.TaskFactorySpec
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-import groovy.transform.TupleConstructor
-
-import java.util.function.Function
-
-@TupleConstructor(defaults = false)
-@NullCheck(includeGenerated = true)
-@EqualsAndHashCode
-final class SyntheticBuildIntermediate implements BuildIntermediate {
-
-    static BuildIntermediate getEmpty() {
-        new SyntheticBuildIntermediate(
-                BuildSpec.getEmpty(),
-                OutputDirFunctions.DEFAULT,
-                SiteSpec.getBlank(),
-                [:],
-                TypesContainer.getEmpty(),
-                SourceProviders.getEmpty(),
-                [],
-                []
-        )
-    }
-
-    static BuildIntermediate get(Map<String, Object> args) {
-        new SyntheticBuildIntermediate(
-                args.buildSpec as BuildSpec ?: BuildSpec.getEmpty(),
-                args.outputDirFunction as Function<Build, OutputDir> ?: OutputDirFunctions.DEFAULT,
-                args.siteSpec as SiteSpec ?: SiteSpec.getBlank(),
-                args.globals as Map<String, Object> ?: [:],
-                args.types as TypesContainer ?: TypesContainer.getEmpty(),
-                args.sources as SourceProviders ?: SourceProviders.getEmpty(),
-                args.taskFactorySpecs as Collection<TaskFactorySpec<TaskFactory>> ?: [],
-                args.includedBuilds as Collection<String> ?: []
-        )
-    }
-
-    static BuildIntermediate get(
-            BuildSpec buildSpec,
-            Function<Build, OutputDir> outputDirFunction,
-            SiteSpec siteSpec,
-            Map<String, Object> globals,
-            TypesContainer types,
-            SourceProviders sources,
-            Collection<TaskFactorySpec<TaskFactory>> taskFactorySpecs,
-            Collection<String> includedBuilds
-    ) {
-        new SyntheticBuildIntermediate(
-                buildSpec,
-                outputDirFunction,
-                siteSpec,
-                globals,
-                types,
-                sources,
-                taskFactorySpecs,
-                includedBuilds
-        )
-    }
-
-    final BuildSpec buildSpec
-    final Function<Build, OutputDir> outputDirFunction
-    final SiteSpec siteSpec
-    final Map<String, Object> globals
-    final TypesContainer types
-    final SourceProviders sources
-    final Collection<TaskFactorySpec<TaskFactory>> taskFactorySpecs
-    final Collection<String> includedBuilds
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/TypesContainer.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/TypesContainer.groovy
deleted file mode 100644
index c5bd6c3..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/TypesContainer.groovy
+++ /dev/null
@@ -1,57 +0,0 @@
-package com.jessebrault.ssg.buildscript
-
-import com.jessebrault.ssg.page.PageType
-import com.jessebrault.ssg.part.PartType
-import com.jessebrault.ssg.template.TemplateType
-import com.jessebrault.ssg.text.TextType
-import com.jessebrault.ssg.util.Monoid
-import com.jessebrault.ssg.util.Monoids
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-import groovy.transform.TupleConstructor
-
-@TupleConstructor(defaults = false)
-@NullCheck(includeGenerated = true)
-@EqualsAndHashCode
-final class TypesContainer {
-
-    static final Monoid<TypesContainer> DEFAULT_MONOID = Monoids.of(getEmpty(), TypesContainer::concat)
-
-    static TypesContainer getEmpty() {
-        new TypesContainer([], [], [], [])
-    }
-
-    static TypesContainer get(Map<String, Object> args) {
-        new TypesContainer(
-                args.textTypes ? args.textTypes as Collection<TextType> : [],
-                args.pageTypes ? args.pageTypes as Collection<PageType> : [],
-                args.templateTypes ? args.templateTypes as Collection<TemplateType> : [],
-                args.partTypes ? args.partTypes as Collection<PartType> : []
-        )
-    }
-
-    static TypesContainer concat(TypesContainer tc0, TypesContainer tc1) {
-        new TypesContainer(
-                tc0.textTypes + tc1.textTypes,
-                tc0.pageTypes + tc1.pageTypes,
-                tc0.templateTypes + tc1.templateTypes,
-                tc0.partTypes + tc1.partTypes
-        )
-    }
-
-    final Collection<TextType> textTypes
-    final Collection<PageType> pageTypes
-    final Collection<TemplateType> templateTypes
-    final Collection<PartType> partTypes
-
-    TypesContainer plus(TypesContainer other) {
-        concat(this, other)
-    }
-
-    @Override
-    String toString() {
-        "TypesContainer(textTypes: ${ this.textTypes }, pageTypes: ${ this.pageTypes }, " +
-                "templateTypes: ${ this.templateTypes }, partTypes: ${ this.partTypes })"
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/BuildDelegate.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/BuildDelegate.groovy
index d375364..4af5aac 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/BuildDelegate.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/BuildDelegate.groovy
@@ -1,283 +1,103 @@
 package com.jessebrault.ssg.buildscript.delegates
 
-import com.jessebrault.ssg.SiteSpec
-import com.jessebrault.ssg.buildscript.*
-import com.jessebrault.ssg.mutable.Mutable
-import com.jessebrault.ssg.mutable.Mutables
-import com.jessebrault.ssg.task.TaskFactory
-import com.jessebrault.ssg.task.TaskFactorySpec
-import com.jessebrault.ssg.util.Monoid
+import com.jessebrault.ssg.model.Model
 import groovy.transform.EqualsAndHashCode
 import groovy.transform.NullCheck
-import groovy.transform.TupleConstructor
-import groovy.transform.stc.ClosureParams
-import groovy.transform.stc.FromString
-import groovy.transform.stc.SimpleType
-
-import java.util.function.Function
-import java.util.function.UnaryOperator
+import groowt.util.fp.property.Property
+import groowt.util.fp.provider.DefaultNamedProvider
+import groowt.util.fp.provider.DefaultNamedSetProvider
+import groowt.util.fp.provider.DefaultSetProvider
+import groowt.util.fp.provider.NamedProvider
+import groowt.util.fp.provider.NamedSetProvider
+import groowt.util.fp.provider.Provider
+import groowt.util.fp.provider.SetProvider
 
 @NullCheck(includeGenerated = true)
 @EqualsAndHashCode(includeFields = true)
 final class BuildDelegate {
 
-    @TupleConstructor(includeFields = true, defaults = false)
-    @NullCheck(includeGenerated = true)
-    @EqualsAndHashCode(includeFields = true)
-    static final class BuildDelegateBuildIntermediate implements BuildIntermediate {
+    final Property<String> siteName = Property.empty().tap {
+        convention = 'An Ssg Site'
+    }
 
-        private final BuildSpec buildSpec
-        private final BuildDelegate delegate
-        private final BuildIntermediate parent
+    final Property<String> baseUrl = Property.empty().tap {
+        convention = ''
+    }
 
-        private final Monoid<SiteSpec> siteSpecMonoid
-        private final Monoid<Map<String, Object>> globalsMonoid
-        private final Monoid<TypesContainer> typesMonoid
-        private final Monoid<SourceProviders> sourcesMonoid
-        private final Monoid<Collection<TaskFactorySpec<TaskFactory>>> taskFactoriesMonoid
-        private final Monoid<Collection<String>> includedBuildsMonoid
+    final Property<File> outputDir = Property.empty().tap {
+        convention = siteName.map { it.replace(' ', '-').toLowerCase() + '-build' }
+    }
 
-        @Override
-        BuildSpec getBuildSpec() {
-            this.buildSpec
+    final Property<Map<String, Object>> globals = Property.empty().tap {
+        convention = [:]
+    }
+
+    private final Set<Provider<File>> textsDirs = []
+    private final Set<NamedProvider<Model>> models = []
+
+    void siteName(String siteName) {
+        this.siteName.set(siteName)
+    }
+
+    void siteName(Provider<String> siteNameProvider) {
+        this.siteName.set(siteNameProvider)
+    }
+
+    void baseUrl(String baseUrl) {
+        this.baseUrl.set(baseUrl)
+    }
+
+    void baseUrl(Provider<String> baseUrlProvider) {
+        this.baseUrl.set(baseUrlProvider)
+    }
+
+    void outputDir(File outputDir) {
+        this.outputDir.set(outputDir)
+    }
+
+    void outputDir(Provider<File> outputDirProvider) {
+        this.outputDir.set(outputDirProvider)
+    }
+
+    void globals(@DelegatesTo(value = GlobalsDelegate, strategy = Closure.DELEGATE_FIRST) Closure<?> globalsClosure) {
+        def globalsDelegate = new GlobalsDelegate()
+        globalsClosure.delegate = globalsDelegate
+        globalsClosure.resolveStrategy = Closure.DELEGATE_FIRST
+        globalsClosure()
+        this.globals.set {
+            this.globals.get() + globalsDelegate
         }
-
-        @Override
-        Function<Build, OutputDir> getOutputDirFunction() {
-            this.delegate.outputDirFunction.getOrElse {
-                this.delegate.outputDirFunctionMapper.match({ parent.outputDirFunction }) {
-                    it.apply(this.parent.outputDirFunction)
-                }
-            }
-        }
-
-        @Override
-        SiteSpec getSiteSpec() {
-            def siteSpecClosure = this.delegate.siteSpecClosure.getOrElse { return { } }
-            def d = new SiteSpecDelegate(this.siteSpecMonoid)
-            siteSpecClosure.delegate = d
-            siteSpecClosure.resolveStrategy = Closure.DELEGATE_FIRST
-            siteSpecClosure(this.parent.siteSpec)
-            if (this.delegate.siteSpecConcatBase.getOrElse { true }) {
-                this.siteSpecMonoid.concat.apply(this.parent.siteSpec, d.result)
-            } else {
-                d.result
-            }
-        }
-
-        @Override
-        Map<String, Object> getGlobals() {
-            def globalsClosure = this.delegate.globalsClosure.getOrElse { return { } }
-            def d = new GlobalsDelegate()
-            globalsClosure.delegate = d
-            globalsClosure.resolveStrategy = Closure.DELEGATE_FIRST
-            globalsClosure(this.parent.globals)
-            if (this.delegate.globalsConcatBase.getOrElse { true }) {
-                this.globalsMonoid.concat.apply(this.parent.globals, d.getResult())
-            } else {
-                d.getResult()
-            }
-        }
-
-        @Override
-        TypesContainer getTypes() {
-            def typesClosure = this.delegate.typesClosure.getOrElse { return { } }
-            def d = new TypesDelegate()
-            typesClosure.delegate = d
-            typesClosure.resolveStrategy = Closure.DELEGATE_FIRST
-            typesClosure(this.parent.types)
-            if (this.delegate.typesConcatBase.getOrElse { true }) {
-                this.typesMonoid.concat.apply(this.parent.types, d.result)
-            } else {
-                d.result
-            }
-        }
-
-        @Override
-        SourceProviders getSources() {
-            def sourcesClosure = this.delegate.sourcesClosure.getOrElse { return { base, types -> } }
-            def d = new SourceProvidersDelegate()
-            sourcesClosure.delegate = d
-            sourcesClosure.resolveStrategy = Closure.DELEGATE_FIRST
-            sourcesClosure(this.parent.sources, this.types)
-            if (this.delegate.sourcesConcatBase.getOrElse { true }) {
-                this.sourcesMonoid.concat.apply(this.parent.sources, d.result)
-            } else {
-                d.result
-            }
-        }
-
-        @Override
-        Collection<TaskFactorySpec<TaskFactory>> getTaskFactorySpecs() {
-            def taskFactoriesClosure = this.delegate.taskFactoriesClosure.getOrElse { return { base, sources -> } }
-            def d = new TaskFactoriesDelegate()
-            taskFactoriesClosure.delegate = d
-            taskFactoriesClosure.resolveStrategy = Closure.DELEGATE_FIRST
-            taskFactoriesClosure(this.parent.taskFactorySpecs, this.sources)
-            if (this.delegate.taskFactoriesConcatBase.getOrElse { true }) {
-                this.taskFactoriesMonoid.concat.apply(this.parent.taskFactorySpecs, d.result)
-            } else {
-                d.result
-            }
-        }
-
-        @Override
-        Collection<String> getIncludedBuilds() {
-            if (this.delegate.includedBuildsConcatBase.getOrElse { true }) {
-                this.includedBuildsMonoid.concat.apply(this.parent.includedBuilds, this.delegate.includedBuilds)
-            } else {
-                this.delegate.includedBuilds
-            }
-        }
-
     }
 
-    private final Mutable<Function<Build, OutputDir>> outputDirFunction = Mutables.getEmpty()
-    private final Mutable<UnaryOperator<Function<Build, OutputDir>>> outputDirFunctionMapper = Mutables.getEmpty()
-
-    private final Mutable<Boolean> siteSpecConcatBase = Mutables.getEmpty()
-    private final Mutable<Closure<?>> siteSpecClosure = Mutables.getEmpty()
-
-    private final Mutable<Boolean> globalsConcatBase = Mutables.getEmpty()
-    private final Mutable<Closure<?>> globalsClosure = Mutables.getEmpty()
-
-    private final Mutable<Boolean> typesConcatBase = Mutables.getEmpty()
-    private final Mutable<Closure<?>> typesClosure = Mutables.getEmpty()
-
-    private final Mutable<Boolean> sourcesConcatBase = Mutables.getEmpty()
-    private final Mutable<Closure<?>> sourcesClosure = Mutables.getEmpty()
-
-    private final Mutable<Boolean> taskFactoriesConcatBase = Mutables.getEmpty()
-    private final Mutable<Closure<?>> taskFactoriesClosure = Mutables.getEmpty()
-
-    private final Mutable<Boolean> includedBuildsConcatBase = Mutables.getEmpty()
-    private final Collection<String> includedBuilds = []
-
-    void setOutputDirFunction(Function<Build, OutputDir> outputDirFunction) {
-        this.outputDirFunction.set(outputDirFunction)
+    void textsDir(File textsDir) {
+        this.textsDirs.add { textsDir }
     }
 
-    void setOutputDir(File file) {
-        this.outputDirFunction.set { new OutputDir(file) }
+    void textsDir(Provider<File> textsDirProvider) {
+        this.textsDirs << textsDirProvider
     }
 
-    void setOutputDir(String path) {
-        this.outputDirFunction.set { new OutputDir(path) }
+    void textsDirs(Set<Provider<File>> textsDirProviders) {
+        textsDirProviders.each { this.textsDir(it) }
     }
 
-    // Maps the *base*
-    void outputDirFunction(UnaryOperator<Function<Build, OutputDir>> mapper) {
-        this.outputDirFunctionMapper.set(mapper)
+    SetProvider<File> getTextsDirs() {
+        new DefaultSetProvider(this.textsDirs)
     }
 
-    void siteSpec(
-            @DelegatesTo(value = SiteSpecDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(value = SimpleType, options = 'com.jessebrault.ssg.SiteSpec')
-            Closure<?> siteSpecClosure
-    ) {
-        this.siteSpec(true, siteSpecClosure)
+    void models(@DelegatesTo(ModelsDelegate) Closure modelsClosure) {
+        def modelsDelegate = new ModelsDelegate()
+        modelsClosure.delegate = modelsDelegate
+        modelsClosure()
+        models.addAll(modelsDelegate.result)
     }
 
-    void siteSpec(
-            boolean concatWithBase,
-            @DelegatesTo(value = SiteSpecDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(value = SimpleType, options = 'com.jessebrault.ssg.SiteSpec')
-            Closure<?> siteSpecClosure
-    ) {
-        this.siteSpecConcatBase.set(concatWithBase)
-        this.siteSpecClosure.set(siteSpecClosure)
+    void models(Set<NamedProvider<Model>> models) {
+        this.models.addAll(models)
     }
 
-    void globals(
-            @DelegatesTo(value = GlobalsDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(value = FromString, options = 'Map<String, Object>')
-            Closure<?> globalsClosure
-    ) {
-        this.globals(true, globalsClosure)
-    }
-
-    void globals(
-            boolean concatWithBase,
-            @DelegatesTo(value = GlobalsDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(value = FromString, options = 'Map<String, Object>')
-            Closure<?> globalsClosure
-    ) {
-        this.globalsConcatBase.set(concatWithBase)
-        this.globalsClosure.set(globalsClosure)
-    }
-
-    void types(
-            @DelegatesTo(value = TypesDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(value = SimpleType, options = 'com.jessebrault.ssg.buildscript.TypesContainer')
-            Closure<?> typesClosure
-    ) {
-        this.types(true, typesClosure)
-    }
-
-    void types(
-            boolean concatWithBase,
-            @DelegatesTo(value = TypesDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(value = SimpleType, options = 'com.jessebrault.ssg.buildscript.TypesContainer')
-            Closure<?> typesClosure
-    ) {
-        this.typesConcatBase.set(concatWithBase)
-        this.typesClosure.set(typesClosure)
-    }
-
-    void sources(
-            @DelegatesTo(value = SourceProvidersDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(
-                    value = FromString,
-                    options = 'com.jessebrault.ssg.buildscript.SourceProviders, com.jessebrault.ssg.buildscript.TypesContainer'
-            )
-            Closure<?> sourcesClosure
-    ) {
-        this.sources(true, sourcesClosure)
-    }
-
-    void sources(
-            boolean concatWithBase,
-            @DelegatesTo(value = SourceProvidersDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(
-                    value = FromString,
-                    options = 'com.jessebrault.ssg.buildscript.SourceProviders, com.jessebrault.ssg.buildscript.TypesContainer'
-            )
-            Closure<?> sourcesClosure
-    ) {
-        this.sourcesConcatBase.set(concatWithBase)
-        this.sourcesClosure.set(sourcesClosure)
-    }
-
-    void taskFactories(
-            @DelegatesTo(value = TaskFactoriesDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(
-                    value = FromString,
-                    options = 'java.util.Collection<com.jessebrault.ssg.task.TaskFactorySpec<com.jessebrault.ssg.task.TaskFactory>>, com.jessebrault.ssg.buildscript.SourceProviders'
-            )
-            Closure<?> taskFactoriesClosure
-    ) {
-        this.taskFactories(true, taskFactoriesClosure)
-    }
-
-    void taskFactories(
-            boolean concatWithBase,
-            @DelegatesTo(value = TaskFactoriesDelegate, strategy = Closure.DELEGATE_FIRST)
-            @ClosureParams(
-                    value = FromString,
-                    options = 'java.util.Collection<com.jessebrault.ssg.task.TaskFactorySpec<com.jessebrault.ssg.task.TaskFactory>>, com.jessebrault.ssg.buildscript.SourceProviders'
-            )
-            Closure<?> taskFactoriesClosure
-    ) {
-        this.taskFactoriesConcatBase.set(concatWithBase)
-        this.taskFactoriesClosure.set(taskFactoriesClosure)
-    }
-
-    void setConcatIncludedBuildsWithBase(boolean value) {
-        this.includedBuildsConcatBase.set(value)
-    }
-
-    void includeBuild(String buildName) {
-        this.includedBuilds << buildName
+    NamedSetProvider<Model> getModels() {
+        new DefaultNamedSetProvider(this.models)
     }
 
 }
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/ModelsDelegate.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/ModelsDelegate.groovy
new file mode 100644
index 0000000..e7c6d23
--- /dev/null
+++ b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/ModelsDelegate.groovy
@@ -0,0 +1,49 @@
+package com.jessebrault.ssg.buildscript.delegates
+
+import com.jessebrault.ssg.model.Model
+import com.jessebrault.ssg.model.Models
+import groowt.util.fp.provider.DefaultNamedProvider
+import groowt.util.fp.provider.NamedProvider
+import groowt.util.fp.provider.Provider
+import org.jetbrains.annotations.ApiStatus
+
+import java.util.function.Supplier
+
+final class ModelsDelegate {
+
+    private final Map<String, Provider<Model>> modelsMap = [:]
+
+    void add(String name, Object modelObject) {
+        this.modelsMap.put(name) { Models.of(name, modelObject ) }
+    }
+
+    void add(Model model) {
+        this.modelsMap.put(model.name) { model }
+    }
+
+    void add(NamedProvider<Model> namedModelProvider) {
+        this.modelsMap.put(namedModelProvider.name, namedModelProvider)
+    }
+
+    void add(String name, Provider<Model> modelProvider) {
+        this.modelsMap.put(name, modelProvider)
+    }
+
+    void add(String name, Supplier objectSupplier) {
+        this.modelsMap.put(name) { Models.ofSupplier(name, objectSupplier) }
+    }
+    
+    void addAll(Map<String, Object> namesAndModels) {
+        namesAndModels.each { name, modelObject ->
+            this.add(name, modelObject)
+        }
+    }
+
+    @ApiStatus.Internal
+    Set<NamedProvider<Model>> getResult() {
+        this.modelsMap.inject([] as Set<NamedProvider<Model>>) { acc, name, modelProvider ->
+            acc << new DefaultNamedProvider(name, modelProvider)
+        }
+    }
+
+}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/SiteSpecDelegate.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/SiteSpecDelegate.groovy
deleted file mode 100644
index 3f3ce0c..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/SiteSpecDelegate.groovy
+++ /dev/null
@@ -1,38 +0,0 @@
-package com.jessebrault.ssg.buildscript.delegates
-
-import com.jessebrault.ssg.SiteSpec
-import com.jessebrault.ssg.util.Zero
-
-import static java.util.Objects.requireNonNull
-
-final class SiteSpecDelegate {
-
-    private String name
-    private String baseUrl
-
-    SiteSpecDelegate(Zero<SiteSpec> siteSpecZero) {
-        this.name = siteSpecZero.zero.name
-        this.baseUrl = siteSpecZero.zero.baseUrl
-    }
-
-    String getName() {
-        return this.name
-    }
-
-    void setName(String name) {
-        this.name = requireNonNull(name)
-    }
-
-    String getBaseUrl() {
-        return this.baseUrl
-    }
-
-    void setBaseUrl(String baseUrl) {
-        this.baseUrl = requireNonNull(baseUrl)
-    }
-
-    SiteSpec getResult() {
-        new SiteSpec(this.name, this.baseUrl)
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/SourceProvidersDelegate.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/SourceProvidersDelegate.groovy
deleted file mode 100644
index 3764ce9..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/SourceProvidersDelegate.groovy
+++ /dev/null
@@ -1,61 +0,0 @@
-package com.jessebrault.ssg.buildscript.delegates
-
-import com.jessebrault.ssg.buildscript.SourceProviders
-import com.jessebrault.ssg.model.Model
-import com.jessebrault.ssg.page.Page
-import com.jessebrault.ssg.part.Part
-import com.jessebrault.ssg.provider.CollectionProvider
-import com.jessebrault.ssg.provider.CollectionProviders
-import com.jessebrault.ssg.template.Template
-import com.jessebrault.ssg.text.Text
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-
-@NullCheck
-@EqualsAndHashCode
-final class SourceProvidersDelegate {
-
-    private CollectionProvider<Text> textsProvider = CollectionProviders.getEmpty()
-    private CollectionProvider<Model<Object>> modelsProvider = CollectionProviders.getEmpty()
-    private CollectionProvider<Page> pagesProvider = CollectionProviders.getEmpty()
-    private CollectionProvider<Template> templatesProvider = CollectionProviders.getEmpty()
-    private CollectionProvider<Part> partsProvider = CollectionProviders.getEmpty()
-
-    private final Map<String, CollectionProvider<Object>> custom = [:]
-
-    void texts(CollectionProvider<Text> textsProvider) {
-        this.textsProvider += textsProvider
-    }
-
-    void models(CollectionProvider<Model<?>> modelsProvider) {
-        this.modelsProvider += modelsProvider
-    }
-
-    void pages(CollectionProvider<Page> pagesProvider) {
-        this.pagesProvider += pagesProvider
-    }
-
-    void templates(CollectionProvider<Template> templatesProvider) {
-        this.templatesProvider += templatesProvider
-    }
-
-    void parts(CollectionProvider<Part> partsProvider) {
-        this.partsProvider += partsProvider
-    }
-
-    void custom(String name, CollectionProvider<?> customProvider) {
-        this.custom.put(name, customProvider as CollectionProvider<Object>)
-    }
-
-    SourceProviders getResult() {
-        new SourceProviders(
-                this.textsProvider,
-                this.modelsProvider,
-                this.pagesProvider,
-                this.templatesProvider,
-                this.partsProvider,
-                this.custom
-        )
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/TaskFactoriesDelegate.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/TaskFactoriesDelegate.groovy
deleted file mode 100644
index 5f68554..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/TaskFactoriesDelegate.groovy
+++ /dev/null
@@ -1,66 +0,0 @@
-package com.jessebrault.ssg.buildscript.delegates
-
-import com.jessebrault.ssg.task.TaskFactory
-import com.jessebrault.ssg.task.TaskFactorySpec
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-
-import java.util.function.Consumer
-import java.util.function.Supplier
-
-@NullCheck
-@EqualsAndHashCode(includeFields = true)
-final class TaskFactoriesDelegate {
-
-    private final Collection<TaskFactorySpec<TaskFactory>> specs = []
-
-    private boolean isRegistered(String name) {
-        this.specs.find { it.name == name } != null
-    }
-
-    private void checkNotRegistered(String name) {
-        if (this.isRegistered(name)) {
-            throw new IllegalArgumentException("a TaskFactory is already registered by the name ${ name }")
-        }
-    }
-
-    void register(String name, Supplier<? extends TaskFactory> factorySupplier) {
-        this.checkNotRegistered(name)
-        this.specs << new TaskFactorySpec<>(name, factorySupplier, [])
-    }
-
-    def <T extends TaskFactory> void register(
-            String name,
-            Supplier<T> factorySupplier,
-            Consumer<T> factoryConfigurator
-    ) {
-        this.checkNotRegistered(name)
-        this.specs << new TaskFactorySpec<>(name, factorySupplier, [factoryConfigurator])
-    }
-
-    void register(TaskFactorySpec<TaskFactory> spec) {
-        this.specs << spec
-    }
-
-    void registerAll(Collection<TaskFactorySpec<TaskFactory>> specs) {
-        this.specs.addAll(specs)
-    }
-
-    def <T extends TaskFactory> void configure(
-            String name,
-            Class<T> factoryClass, // Dummy so we get better auto-complete
-            Consumer<T> factoryConfigurator
-    ) {
-        if (!this.isRegistered(name)) {
-            throw new IllegalArgumentException("there is no TaskFactory registered by name ${ name }")
-        }
-        def spec = this.specs.find { it.name == name }
-        // Potentially dangerous, but the configurators Collection *should* only contain the correct types.
-        spec.configurators << (factoryConfigurator as Consumer<TaskFactory>)
-    }
-
-    Collection<TaskFactorySpec<TaskFactory>> getResult() {
-        this.specs
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/TypesDelegate.groovy b/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/TypesDelegate.groovy
deleted file mode 100644
index adb4d46..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/buildscript/delegates/TypesDelegate.groovy
+++ /dev/null
@@ -1,24 +0,0 @@
-package com.jessebrault.ssg.buildscript.delegates
-
-import com.jessebrault.ssg.buildscript.TypesContainer
-import com.jessebrault.ssg.page.PageType
-import com.jessebrault.ssg.part.PartType
-import com.jessebrault.ssg.template.TemplateType
-import com.jessebrault.ssg.text.TextType
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-
-@NullCheck
-@EqualsAndHashCode
-final class TypesDelegate {
-
-    final Collection<TextType> textTypes = []
-    final Collection<PageType> pageTypes = []
-    final Collection<TemplateType> templateTypes = []
-    final Collection<PartType> partTypes = []
-
-    TypesContainer getResult() {
-        new TypesContainer(this.textTypes, this.pageTypes, this.templateTypes, this.partTypes)
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/model/Models.groovy b/api/src/main/groovy/com/jessebrault/ssg/model/Models.groovy
index e5997e9..eef541a 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/model/Models.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/model/Models.groovy
@@ -1,5 +1,8 @@
 package com.jessebrault.ssg.model
 
+import groowt.util.fp.provider.NamedProvider
+import groowt.util.fp.provider.Provider
+
 import java.util.function.Supplier
 
 final class Models {
@@ -8,10 +11,18 @@ final class Models {
         new SimpleModel<>(name, t)
     }
 
-    static <T> Model<T> fromSupplier(String name, Supplier<T> tClosure) {
+    static <T> Model<T> ofSupplier(String name, Supplier<? extends T> tClosure) {
         new SupplierBasedModel<>(name, tClosure)
     }
 
+    static <T> Model<T> ofProvider(String name, Provider<? extends T> modelProvider) {
+        new ProviderModel<T>(name, modelProvider)
+    }
+
+    static <T> Model<T> ofNamedProvider(NamedProvider<? extends T> namedModelProvider) {
+        new ProviderModel<T>(namedModelProvider.name, namedModelProvider)
+    }
+
     private Models() {}
 
 }
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/SupplierBasedProvider.groovy b/api/src/main/groovy/com/jessebrault/ssg/model/ProviderModel.groovy
similarity index 50%
rename from api/src/main/groovy/com/jessebrault/ssg/provider/SupplierBasedProvider.groovy
rename to api/src/main/groovy/com/jessebrault/ssg/model/ProviderModel.groovy
index 9f6c61c..7cedbad 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/SupplierBasedProvider.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/model/ProviderModel.groovy
@@ -1,28 +1,27 @@
-package com.jessebrault.ssg.provider
+package com.jessebrault.ssg.model
 
 import groovy.transform.EqualsAndHashCode
 import groovy.transform.NullCheck
 import groovy.transform.PackageScope
 import groovy.transform.TupleConstructor
-
-import java.util.function.Supplier
+import groowt.util.fp.provider.Provider
 
 @PackageScope
 @TupleConstructor(includeFields = true, defaults = false)
 @NullCheck(includeGenerated = true)
-@EqualsAndHashCode(includeFields = true)
-final class SupplierBasedProvider<T> extends AbstractProvider<T> {
+@EqualsAndHashCode
+class ProviderModel<T> implements Model<T> {
 
-    private final Supplier<T> supplier
+    final String name
+    private final Provider<T> modelProvider
 
     @Override
-    T provide() {
-        this.supplier.get()
+    T get() {
+        this.modelProvider.get()
     }
 
     @Override
     String toString() {
-        "SupplierBasedProvider(supplier: ${ this.supplier })"
+        "ProviderModel($this.name)"
     }
-
 }
diff --git a/api/src/main/groovy/com/jessebrault/ssg/model/SupplierBasedModel.groovy b/api/src/main/groovy/com/jessebrault/ssg/model/SupplierBasedModel.groovy
index 3b6a9d1..b65bc6b 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/model/SupplierBasedModel.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/model/SupplierBasedModel.groovy
@@ -8,13 +8,17 @@ import groovy.transform.TupleConstructor
 import java.util.function.Supplier
 
 @PackageScope
-@TupleConstructor(includeFields = true, defaults = false)
 @NullCheck(includeGenerated = true)
 @EqualsAndHashCode(includeFields = true)
 final class SupplierBasedModel<T> implements Model<T> {
 
     final String name
-    private final Supplier<T> supplier
+    private final Supplier<? extends T> supplier
+
+    SupplierBasedModel(String name, Supplier<? extends T> supplier) {
+        this.name = name
+        this.supplier = supplier
+    }
 
     @Override
     T get() {
diff --git a/api/src/main/groovy/com/jessebrault/ssg/mutable/Mutable.java b/api/src/main/groovy/com/jessebrault/ssg/mutable/Mutable.java
index f029a24..218b70b 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/mutable/Mutable.java
+++ b/api/src/main/groovy/com/jessebrault/ssg/mutable/Mutable.java
@@ -6,6 +6,7 @@ import java.util.Optional;
 import java.util.function.*;
 
 @ApiStatus.Experimental
+@Deprecated
 public interface Mutable<T> {
     T get();
     void set(T t);
diff --git a/api/src/main/groovy/com/jessebrault/ssg/property/Properties.groovy b/api/src/main/groovy/com/jessebrault/ssg/property/Properties.groovy
deleted file mode 100644
index 19f9ec9..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/property/Properties.groovy
+++ /dev/null
@@ -1,11 +0,0 @@
-package com.jessebrault.ssg.property
-
-final class Properties {
-
-    static <T> Property<T> get() {
-        new SimpleProperty<>()
-    }
-
-    private Properties() {}
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/property/Property.groovy b/api/src/main/groovy/com/jessebrault/ssg/property/Property.groovy
deleted file mode 100644
index 48574d1..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/property/Property.groovy
+++ /dev/null
@@ -1,38 +0,0 @@
-package com.jessebrault.ssg.property
-
-import com.jessebrault.ssg.provider.Provider
-
-import java.util.function.Function
-import java.util.function.UnaryOperator
-
-interface Property<T> extends Provider<T> {
-
-    void set(T t)
-    void set(Provider<T> provider)
-    void unset()
-
-    default void leftShift(T t) {
-        this.set(t)
-    }
-
-    default void leftShift(Provider<T> provider) {
-        this.set(provider)
-    }
-
-    T getConvention()
-    void setConvention(T t)
-    void setConvention(Provider<T> provider)
-    void unsetConvention()
-
-    void map(UnaryOperator<T> operator)
-    void flatMap(Function<T, Provider<T>> function)
-
-    default void rightShift(UnaryOperator<T> operator) {
-        this.map(operator)
-    }
-
-    default void rightShift(Function<T, Provider<T>> function) {
-        this.flatMap(function)
-    }
-
-}
\ No newline at end of file
diff --git a/api/src/main/groovy/com/jessebrault/ssg/property/SimpleProperty.groovy b/api/src/main/groovy/com/jessebrault/ssg/property/SimpleProperty.groovy
deleted file mode 100644
index 09f3f03..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/property/SimpleProperty.groovy
+++ /dev/null
@@ -1,82 +0,0 @@
-package com.jessebrault.ssg.property
-
-import com.jessebrault.ssg.provider.AbstractProvider
-import com.jessebrault.ssg.provider.Provider
-import com.jessebrault.ssg.provider.Providers
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-import groovy.transform.PackageScope
-
-import java.util.function.Function
-import java.util.function.UnaryOperator
-
-@PackageScope
-@NullCheck
-@EqualsAndHashCode(includeFields = true)
-final class SimpleProperty<T> extends AbstractProvider<T> implements Property<T> {
-
-    private Provider<T> convention = Providers.getEmpty()
-    private Provider<T> tProvider = Providers.getEmpty()
-
-    @Override
-    T provide() {
-        this.tProvider.present ? this.tProvider.provide() : this.convention.provide()
-    }
-
-    @Override
-    void set(T t) {
-        this.tProvider = Providers.of(t)
-    }
-
-    @Override
-    void set(Provider<T> provider) {
-        this.tProvider = provider
-    }
-
-    @Override
-    void unset() {
-        this.tProvider = Providers.getEmpty()
-    }
-
-    @Override
-    T getConvention() {
-        this.convention.provide()
-    }
-
-    @Override
-    void setConvention(T t) {
-        this.convention = Providers.of(t)
-    }
-
-    @Override
-    void setConvention(Provider<T> provider) {
-        this.convention = provider
-    }
-
-    @Override
-    void unsetConvention() {
-        this.convention = Providers.getEmpty()
-    }
-
-    @Override
-    void map(UnaryOperator<T> operator) {
-        def oldTProvider = this.tProvider
-        this.tProvider = Providers.fromSupplier {
-            operator.apply(oldTProvider.provide())
-        }
-    }
-
-    @Override
-    void flatMap(Function<T, Provider<T>> function) {
-        def oldTProvider = this.tProvider
-        this.tProvider = Providers.fromSupplier {
-            function.apply(oldTProvider.provide()).provide()
-        }
-    }
-
-    @Override
-    String toString() {
-        "SimpleProperty(convention: ${ this.convention }, tProvider: ${ this.tProvider })"
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/AbstractCollectionProvider.groovy b/api/src/main/groovy/com/jessebrault/ssg/provider/AbstractCollectionProvider.groovy
index 3ac8267..9525c88 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/AbstractCollectionProvider.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/provider/AbstractCollectionProvider.groovy
@@ -9,31 +9,16 @@ import groovy.transform.TupleConstructor
 @EqualsAndHashCode(includeFields = true)
 abstract class AbstractCollectionProvider<T> implements CollectionProvider<T> {
 
-    static <T> CollectionProvider<T> concat(
-            CollectionProvider<T> cp,
-            Provider<T> p
-    ) {
-        new SupplierBasedCollectionProvider<>([cp], [p], {
-            [*cp.provide(), p.provide()]
-        })
-    }
-
     static <T> CollectionProvider<T> concat(
             CollectionProvider<T> cp0,
             CollectionProvider<T> cp1
     ) {
-        new SupplierBasedCollectionProvider<>([cp0, cp1], [], {
+        new SupplierBasedCollectionProvider<>([cp0, cp1], {
             cp0.provide() + cp1.provide()
         })
     }
 
     private final Collection<CollectionProvider<T>> collectionProviderChildren
-    private final Collection<Provider<T>> providerChildren
-
-    @Override
-    boolean contains(Provider<T> provider) {
-        provider in this
-    }
 
     @Override
     boolean contains(CollectionProvider<T> collectionProvider) {
@@ -68,36 +53,11 @@ abstract class AbstractCollectionProvider<T> implements CollectionProvider<T> {
         this.getChildrenOfType(DirectoryCollectionProvider)
     }
 
-    @Override
-    CollectionProvider<T> plus(Provider<T> other) {
-        concat(this, other)
-    }
-
     @Override
     CollectionProvider<T> plus(CollectionProvider<T> other) {
         concat(this, other)
     }
 
-    private boolean searchProviderChildrenFor(Provider<T> descendant) {
-        this.providerChildren.inject(false) { acc, childProvider ->
-            acc || descendant in childProvider
-        }
-    }
-
-    private boolean searchCollectionProviderChildrenFor(Provider<T> descendant) {
-        this.collectionProviderChildren.inject(false) { acc, childProvider ->
-            acc || descendant in childProvider
-        }
-    }
-
-    @Override
-    boolean isCase(Provider<T> provider) {
-        provider in this.providerChildren
-                || this.searchProviderChildrenFor(provider)
-                || this.searchCollectionProviderChildrenFor(provider)
-
-    }
-
     @Override
     boolean isCase(CollectionProvider<T> collectionProvider) {
         collectionProvider == this
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/AbstractProvider.groovy b/api/src/main/groovy/com/jessebrault/ssg/provider/AbstractProvider.groovy
deleted file mode 100644
index 680ba38..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/AbstractProvider.groovy
+++ /dev/null
@@ -1,40 +0,0 @@
-package com.jessebrault.ssg.provider
-
-abstract class AbstractProvider<T> implements Provider<T> {
-
-    static <T> CollectionProvider<T> concat(
-            Provider<T> p0,
-            Provider<T> p1
-    ) {
-        new SupplierBasedCollectionProvider<>([], [p0, p1], {
-            [p0.provide(), p1.provide()]
-        })
-    }
-
-    static <T> CollectionProvider<T> concat(
-            Provider<T> p0,
-            CollectionProvider<T> p1
-    ) {
-        new SupplierBasedCollectionProvider<>([p1], [p0], {
-            [p0.provide(), *p1.provide()]
-        })
-    }
-
-    @Override
-    CollectionProvider<T> plus(Provider<T> other) {
-        concat(this, other)
-    }
-
-    @Override
-    CollectionProvider<T> plus(CollectionProvider<T> other) {
-        concat(this, other)
-    }
-
-    @Override
-    CollectionProvider<T> asType(Class<CollectionProvider> collectionProviderClass) {
-        new SupplierBasedCollectionProvider<>({
-            [this.provide() as T]
-        })
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/CollectionProvider.java b/api/src/main/groovy/com/jessebrault/ssg/provider/CollectionProvider.java
index f278690..835bfcf 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/CollectionProvider.java
+++ b/api/src/main/groovy/com/jessebrault/ssg/provider/CollectionProvider.java
@@ -7,7 +7,6 @@ import java.util.Collection;
 public interface CollectionProvider<T> {
     Collection<T> provide();
 
-    boolean contains(Provider<T> provider);
     boolean contains(CollectionProvider<T> collectionProvider);
 
     @ApiStatus.Experimental
@@ -18,9 +17,7 @@ public interface CollectionProvider<T> {
 
     Collection<DirectoryCollectionProvider<T>> getDirectoryCollectionProviderChildren();
 
-    CollectionProvider<T> plus(Provider<T> other);
     CollectionProvider<T> plus(CollectionProvider<T> other);
 
-    boolean isCase(Provider<T> provider);
     boolean isCase(CollectionProvider<T> collectionProvider);
-}
\ No newline at end of file
+}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/EmptyProvider.groovy b/api/src/main/groovy/com/jessebrault/ssg/provider/EmptyProvider.groovy
deleted file mode 100644
index f3072cf..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/EmptyProvider.groovy
+++ /dev/null
@@ -1,41 +0,0 @@
-package com.jessebrault.ssg.provider
-
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-import groovy.transform.PackageScope
-
-@PackageScope
-@NullCheck
-@EqualsAndHashCode
-final class EmptyProvider<T> implements Provider<T> {
-
-    @Override
-    T provide() {
-        throw new NullPointerException('EmptyProvider cannot provide a value.')
-    }
-
-    @Override
-    CollectionProvider<T> plus(CollectionProvider<T> other) {
-        CollectionProviders.fromSupplier {
-            other.provide()
-        }
-    }
-
-    @Override
-    CollectionProvider<T> plus(Provider<T> other) {
-        CollectionProviders.fromSupplier {
-            [other.provide()] as Collection<T>
-        }
-    }
-
-    @Override
-    CollectionProvider<T> asType(Class<CollectionProvider> collectionProviderClass) {
-        CollectionProviders.fromCollection([]) as CollectionProvider<T>
-    }
-
-    @Override
-    String toString() {
-        "EmptyProvider()"
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/Provider.groovy b/api/src/main/groovy/com/jessebrault/ssg/provider/Provider.groovy
deleted file mode 100644
index 7a771a8..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/Provider.groovy
+++ /dev/null
@@ -1,8 +0,0 @@
-package com.jessebrault.ssg.provider
-
-interface Provider<T> {
-    T provide()
-    CollectionProvider<T> plus(Provider<T> other)
-    CollectionProvider<T> plus(CollectionProvider<T> other)
-    CollectionProvider<T> asType(Class<CollectionProvider> collectionProviderClass)
-}
\ No newline at end of file
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/Providers.groovy b/api/src/main/groovy/com/jessebrault/ssg/provider/Providers.groovy
deleted file mode 100644
index 8d62396..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/Providers.groovy
+++ /dev/null
@@ -1,34 +0,0 @@
-package com.jessebrault.ssg.provider
-
-import groovy.transform.NullCheck
-
-import java.util.function.Supplier
-
-@NullCheck
-final class Providers {
-
-    static <T> Provider<T> getEmpty() {
-        new EmptyProvider<>()
-    }
-
-    static <T> Provider<T> of(T t) {
-        new SimpleProvider<>(t)
-    }
-
-    static <T> Provider<T> fromSupplier(Supplier<T> supplier) {
-        new SupplierBasedProvider<>(supplier)
-    }
-
-    static <T> CollectionProvider<T> concat(Provider<T> ...providers) {
-        concat(List.of(providers))
-    }
-
-    static <T> CollectionProvider<T> concat(Collection<Provider<T>> providers) {
-        providers.inject(CollectionProviders.<T>getEmpty()) { acc, val ->
-            acc + val
-        }
-    }
-
-    private Providers() {}
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/SimpleProvider.groovy b/api/src/main/groovy/com/jessebrault/ssg/provider/SimpleProvider.groovy
deleted file mode 100644
index 2f7e661..0000000
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/SimpleProvider.groovy
+++ /dev/null
@@ -1,26 +0,0 @@
-package com.jessebrault.ssg.provider
-
-import groovy.transform.EqualsAndHashCode
-import groovy.transform.NullCheck
-import groovy.transform.PackageScope
-import groovy.transform.TupleConstructor
-
-@PackageScope
-@TupleConstructor(defaults = false, includeFields = true)
-@NullCheck(includeGenerated = true)
-@EqualsAndHashCode(includeFields = true)
-final class SimpleProvider<T> extends AbstractProvider<T> {
-
-    private final T t
-
-    @Override
-    T provide() {
-        this.t
-    }
-
-    @Override
-    String toString() {
-        "SimpleProvider(t: ${ this.t })"
-    }
-
-}
diff --git a/api/src/main/groovy/com/jessebrault/ssg/provider/SupplierBasedCollectionProvider.groovy b/api/src/main/groovy/com/jessebrault/ssg/provider/SupplierBasedCollectionProvider.groovy
index 5c2f0a0..aa22fee 100644
--- a/api/src/main/groovy/com/jessebrault/ssg/provider/SupplierBasedCollectionProvider.groovy
+++ b/api/src/main/groovy/com/jessebrault/ssg/provider/SupplierBasedCollectionProvider.groovy
@@ -15,15 +15,14 @@ final class SupplierBasedCollectionProvider<T> extends AbstractCollectionProvide
 
     SupplierBasedCollectionProvider(
             Collection<CollectionProvider<T>> collectionProviderChildren,
-            Collection<Provider<T>> providerChildren,
             Supplier<Collection<T>> supplier
     ) {
-        super(collectionProviderChildren, providerChildren)
+        super(collectionProviderChildren)
         this.supplier = supplier
     }
 
     SupplierBasedCollectionProvider(Supplier<Collection<T>> supplier) {
-        this([], [], supplier)
+        this([], supplier)
     }
 
     @Override
diff --git a/api/src/test/groovy/com/jessebrault/ssg/buildscript/BuildScriptsTests.groovy b/api/src/test/groovy/com/jessebrault/ssg/buildscript/BuildScriptsTests.groovy
index f6f5804..89cd393 100644
--- a/api/src/test/groovy/com/jessebrault/ssg/buildscript/BuildScriptsTests.groovy
+++ b/api/src/test/groovy/com/jessebrault/ssg/buildscript/BuildScriptsTests.groovy
@@ -2,6 +2,7 @@ package com.jessebrault.ssg.buildscript
 
 import com.jessebrault.ssg.SiteSpec
 import groovy.transform.NullCheck
+import org.junit.jupiter.api.Disabled
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
 import org.mockito.Mock
@@ -10,7 +11,6 @@ import org.mockito.junit.jupiter.MockitoExtension
 import java.util.function.Consumer
 import java.util.function.Function
 
-import static BuildScriptRunner.runClosureScript
 import static org.junit.jupiter.api.Assertions.assertEquals
 import static org.mockito.Mockito.verify
 
@@ -52,7 +52,7 @@ final class BuildScriptsTests {
             Map<String, Object> binding = [:],
             Consumer<BuildScriptBase> configureBase = { }
     ) {
-        new BuildScriptRunner(urls).runBuildScript(scriptName, binding, configureBase)
+        new FileBuildScriptGetter(urls).getBuildInfo(scriptName, binding, configureBase)
     }
 
     @Test
@@ -164,6 +164,8 @@ final class BuildScriptsTests {
     }
 
     @Test
+    @Disabled
+    @Deprecated(forRemoval = true)
     void oneBuildWithAbstractParent() {
         def r = runClosureScript {
             abstractBuild(name: 'parent') {
diff --git a/api/src/testFixtures/groovy/com/jessebrault/ssg/provider/AbstractCollectionProviderTests.groovy b/api/src/testFixtures/groovy/com/jessebrault/ssg/provider/AbstractCollectionProviderTests.groovy
index 3033aa7..9e64f55 100644
--- a/api/src/testFixtures/groovy/com/jessebrault/ssg/provider/AbstractCollectionProviderTests.groovy
+++ b/api/src/testFixtures/groovy/com/jessebrault/ssg/provider/AbstractCollectionProviderTests.groovy
@@ -20,11 +20,6 @@ abstract class AbstractCollectionProviderTests {
 
     protected static final Logger logger = LoggerFactory.getLogger(AbstractCollectionProviderTests)
 
-    @SuppressWarnings('GrMethodMayBeStatic')
-    protected Provider<Integer> getProvider(Integer t) {
-        Providers.of(t)
-    }
-
     protected abstract CollectionProvider<Integer> getCollectionProvider(Collection<Integer> ts)
 
     @Test
@@ -75,12 +70,10 @@ abstract class AbstractCollectionProviderTests {
 
     @TestFactory
     Collection<DynamicTest> containsAndIsCaseProviderChildren() {
-        def p0 = this.getProvider(0)
         def p1 = this.getCollectionProvider([])
         def sum = p0 + p1
         ([
                 contains: { CollectionProvider<Integer> p ->
-                    assertTrue(p.contains(p0))
                     assertTrue(p.contains(p1))
                 } as Consumer<CollectionProvider<Integer>>,
                 in: { CollectionProvider<Integer> p ->
diff --git a/cli/src/main/resources/com/jessebrault/ssg/default.groovy b/cli/src/main/resources/com/jessebrault/ssg/default.groovy
new file mode 100644
index 0000000..b4c9897
--- /dev/null
+++ b/cli/src/main/resources/com/jessebrault/ssg/default.groovy
@@ -0,0 +1,10 @@
+import com.jessebrault.ssg.buildscript.BuildScriptBase
+import groovy.transform.BaseScript
+
+@BaseScript
+BuildScriptBase base
+
+build {
+    siteName 'My Site'
+    baseUrl 'https://mysite.com'
+}
diff --git a/cli/src/main/resources/com/jessebrault/ssg/preview.groovy b/cli/src/main/resources/com/jessebrault/ssg/preview.groovy
new file mode 100644
index 0000000..175988f
--- /dev/null
+++ b/cli/src/main/resources/com/jessebrault/ssg/preview.groovy
@@ -0,0 +1,10 @@
+import com.jessebrault.ssg.buildscript.BuildScriptBase
+import groovy.transform.BaseScript
+
+@BaseScript
+BuildScriptBase base
+
+build {
+    extending 'default'
+    baseUrl baseUrl.map { defaultBaseUrl -> defaultBaseUrl + '/preview' }
+}
diff --git a/cli/src/main/resources/com/jessebrault/ssg/production.groovy b/cli/src/main/resources/com/jessebrault/ssg/production.groovy
new file mode 100644
index 0000000..a4e3ffd
--- /dev/null
+++ b/cli/src/main/resources/com/jessebrault/ssg/production.groovy
@@ -0,0 +1,9 @@
+import com.jessebrault.ssg.buildscript.BuildScriptBase
+import groovy.transform.BaseScript
+
+@BaseScript
+BuildScriptBase base
+
+build {
+    extending 'default'
+}
diff --git a/ssg-0.4.0.md b/ssg-0.4.0.md
index 43e5469..c9b664d 100644
--- a/ssg-0.4.0.md
+++ b/ssg-0.4.0.md
@@ -24,10 +24,43 @@ Have the following layout of dirs and files. It is a combined gradle/ssg project
   - production.ssg.groovy: a 'production' build
   - preview.ssg.groovy: a 'preview' build
 - texts: a general folder for texts and other textual data, can be .md, .txt, .html, etc.
-- build.gradle: the root project build.gradle 
+- build.gradle: the root project build.gradle
 - settings.gradle: the usual gradle settings
 
 ## Api TODO
 - [ ] Move from `Provider`/`Property` in `api` to `groowt.util.provider`.
 - [ ] Move from all the fp-util stuff to `groowt.util.fp`.
 - [ ] Get rid of graph-dependency.
+
+## New Build Script DSL
+
+Simple example:
+```groovy
+extendsFrom('default')
+
+// isAbstract = true
+
+siteName = 'Hello, World!'
+baseUrl = 'https://helloworld.com/'
+buildDir = new File('hello-world-build')
+
+globals {
+    someProp = 'Some property.'
+}
+
+includedBuilds << 'anotherBuild'
+```
+
+Example with models:
+```groovy
+Set<NamedModel> myModels = [
+        new NamedModel(name: 'thing0'),
+        new NamedModel(name: 'thing1')
+]
+
+models {
+    myModels.each {
+        add(it.name, it)
+    }
+}
+```