diff --git a/base/loading.jl b/base/loading.jl
index 986efc1e1e5fb..fd8eba6bed460 100644
--- a/base/loading.jl
+++ b/base/loading.jl
@@ -611,6 +611,23 @@ function env_project_file(env::String)::Union{Bool,String}
     end
 end
 
+function base_project(project_file)
+    base_dir = abspath(joinpath(dirname(project_file), ".."))
+    base_project_file = env_project_file(base_dir)
+    base_project_file isa String || return nothing
+    d = parsed_toml(base_project_file)
+    workspace = get(d, "workspace", nothing)::Union{Dict{String, Any}, Nothing}
+    if workspace === nothing
+        return nothing
+    end
+    projects = get(workspace, "projects", nothing)::Union{Vector{String}, Nothing, String}
+    projects === nothing && return nothing
+    if projects isa Vector && basename(dirname(project_file)) in projects
+        return base_project_file
+    end
+    return nothing
+end
+
 function project_deps_get(env::String, name::String)::Union{Nothing,PkgId}
     project_file = env_project_file(env)
     if project_file isa String
@@ -622,21 +639,27 @@ function project_deps_get(env::String, name::String)::Union{Nothing,PkgId}
     return nothing
 end
 
+function package_get(project_file, where::PkgId, name::String)
+    proj = project_file_name_uuid(project_file, where.name)
+    if proj == where
+        # if `where` matches the project, use [deps] section as manifest, and stop searching
+        pkg_uuid = explicit_project_deps_get(project_file, name)
+        return PkgId(pkg_uuid, name)
+    end
+    return nothing
+end
+
 function manifest_deps_get(env::String, where::PkgId, name::String)::Union{Nothing,PkgId}
     uuid = where.uuid
     @assert uuid !== nothing
     project_file = env_project_file(env)
     if project_file isa String
-        # first check if `where` names the Project itself
-        proj = project_file_name_uuid(project_file, where.name)
-        if proj == where
-            # if `where` matches the project, use [deps] section as manifest, and stop searching
-            pkg_uuid = explicit_project_deps_get(project_file, name)
-            return PkgId(pkg_uuid, name)
-        end
+        pkg = package_get(project_file, where, name)
+        pkg === nothing || return pkg
         d = parsed_toml(project_file)
         exts = get(d, "extensions", nothing)::Union{Dict{String, Any}, Nothing}
         if exts !== nothing
+            proj = project_file_name_uuid(project_file, where.name)
             # Check if `where` is an extension of the project
             if where.name in keys(exts) && where.uuid == uuid5(proj.uuid::UUID, where.name)
                 # Extensions can load weak deps...
@@ -726,6 +749,14 @@ function project_file_path(project_file::String)
     joinpath(dirname(project_file), get(d, "path", "")::String)
 end
 
+function workspace_manifest(project_file)
+    base = base_project(project_file)
+    if base !== nothing
+        return project_file_manifest_path(base)
+    end
+    return nothing
+end
+
 # find project file's corresponding manifest file
 function project_file_manifest_path(project_file::String)::Union{Nothing,String}
     @lock require_lock begin
@@ -736,6 +767,10 @@ function project_file_manifest_path(project_file::String)::Union{Nothing,String}
     end
     dir = abspath(dirname(project_file))
     d = parsed_toml(project_file)
+    base_manifest = workspace_manifest(project_file)
+    if base_manifest !== nothing
+        return base_manifest
+    end
     explicit_manifest = get(d, "manifest", nothing)::Union{String, Nothing}
     manifest_path = nothing
     if explicit_manifest !== nothing
@@ -3355,9 +3390,27 @@ function recursive_prefs_merge(base::Dict{String, Any}, overrides::Dict{String,
     return new_base
 end
 
+function get_projects_workspace_to_root(project_file)
+    projects = String[project_file]
+    while true
+        project_file = base_project(project_file)
+        if project_file === nothing
+            return projects
+        end
+        push!(projects, project_file)
+    end
+end
+
 function get_preferences(uuid::Union{UUID,Nothing} = nothing)
     merged_prefs = Dict{String,Any}()
-    for env in reverse(load_path())
+    loadpath = load_path()
+    projects_to_merge_prefs = String[]
+    append!(projects_to_merge_prefs, Iterators.drop(loadpath, 1))
+    if length(loadpath) >= 1
+        prepend!(projects_to_merge_prefs, get_projects_workspace_to_root(first(loadpath)))
+    end
+
+    for env in reverse(projects_to_merge_prefs)
         project_toml = env_project_file(env)
         if !isa(project_toml, String)
             continue
diff --git a/base/precompilation.jl b/base/precompilation.jl
index 50b84ad829d0a..a823b2b579852 100644
--- a/base/precompilation.jl
+++ b/base/precompilation.jl
@@ -1,7 +1,8 @@
 module Precompilation
 
 using Base: PkgId, UUID, SHA1, parsed_toml, project_file_name_uuid, project_names,
-            project_file_manifest_path, get_deps, preferences_names, isaccessibledir, isfile_casesensitive
+            project_file_manifest_path, get_deps, preferences_names, isaccessibledir, isfile_casesensitive,
+            base_project
 
 # This is currently only used for pkgprecompile but the plan is to use this in code loading in the future
 # see the `kc/codeloading2.0` branch
@@ -59,6 +60,19 @@ function ExplicitEnv(envpath::String=Base.active_project())
         delete!(project_deps, name)
     end
 
+    # This project might be a package, in that case, that is also a "dependency"
+    # of the project.
+    proj_name = get(project_d, "name", nothing)::Union{String, Nothing}
+    _proj_uuid = get(project_d, "uuid", nothing)::Union{String, Nothing}
+    proj_uuid = _proj_uuid === nothing ? nothing : UUID(_proj_uuid)
+
+    project_is_package = proj_name !== nothing && proj_uuid !== nothing
+    if project_is_package
+        # TODO: Error on missing uuid?
+        project_deps[proj_name] = UUID(proj_uuid)
+        names[UUID(proj_uuid)] = proj_name
+    end
+
     project_extensions = Dict{String, Vector{UUID}}()
     # Collect all extensions of the project
     for (name, triggers::Union{String, Vector{String}}) in get(Dict{String, Any}, project_d, "extensions")::Dict{String, Any}
@@ -76,18 +90,6 @@ function ExplicitEnv(envpath::String=Base.active_project())
         project_extensions[name] = uuids
     end
 
-    # This project might be a package, in that case, that is also a "dependency"
-    # of the project.
-    proj_name = get(project_d, "name", nothing)::Union{String, Nothing}
-    _proj_uuid = get(project_d, "uuid", nothing)::Union{String, Nothing}
-    proj_uuid = _proj_uuid === nothing ? nothing : UUID(_proj_uuid)
-
-    if proj_name !== nothing && proj_uuid !== nothing
-        # TODO: Error on missing uuid?
-        project_deps[proj_name] = UUID(proj_uuid)
-        names[UUID(proj_uuid)] = proj_name
-    end
-
     manifest = project_file_manifest_path(envpath)
     manifest_d = manifest === nothing ? Dict{String, Any}() : parsed_toml(manifest)
 
@@ -355,8 +357,8 @@ function precompilepkgs(pkgs::Vector{String}=String[];
                         configs::Union{Config,Vector{Config}}=(``=>Base.CacheFlags()),
                         io::IO=stderr,
                         # asking for timing disables fancy mode, as timing is shown in non-fancy mode
-                        fancyprint::Bool = can_fancyprint(io) && !timing
-                    )
+                        fancyprint::Bool = can_fancyprint(io) && !timing,
+                        manifest::Bool=false,)
 
     configs = configs isa Config ? [configs] : configs
 
@@ -512,9 +514,15 @@ function precompilepkgs(pkgs::Vector{String}=String[];
     end
     @debug "precompile: circular dep check done"
 
-    # if a list of packages is given, restrict to dependencies of given packages
-    if !isempty(pkgs)
-         function collect_all_deps(depsmap, dep, alldeps=Set{Base.PkgId}())
+    if !manifest
+        if isempty(pkgs)
+            pkgs = [pkg.name for pkg in direct_deps]
+            target = "all packages"
+        else
+            target = join(pkgs, ", ")
+        end
+        # restrict to dependencies of given packages
+        function collect_all_deps(depsmap, dep, alldeps=Set{Base.PkgId}())
             for _dep in depsmap[dep]
                 if !(_dep in alldeps)
                     push!(alldeps, _dep)
@@ -544,13 +552,13 @@ function precompilepkgs(pkgs::Vector{String}=String[];
                 # TODO: actually handle packages from other envs in the stack
                 return
             else
-                error("No direct dependencies outside of the sysimage found matching $(repr(pkgs))")
+                return
             end
         end
-        target = join(pkgs, ", ")
     else
-        target = "project"
+        target = "manifest"
     end
+
     nconfigs = length(configs)
     if nconfigs == 1
         if !isempty(only(configs)[1])
diff --git a/doc/src/manual/code-loading.md b/doc/src/manual/code-loading.md
index 25ebf3475f34c..9e753d2a7de33 100644
--- a/doc/src/manual/code-loading.md
+++ b/doc/src/manual/code-loading.md
@@ -394,6 +394,28 @@ are stored in the manifest file in the section for that package. The dependency
 a package are the same as for its "parent" except that the listed extension dependencies are also considered as
 dependencies.
 
+### [Workspaces](@id workspaces)
+
+A project file can define a workspace by giving a set of projects that is part of that workspace:
+
+```toml
+[workspace]
+projects = ["test", "benchmarks", "docs", "SomePackage"]
+```
+
+Each subfolder contains its own `Project.toml` file, which may include additional dependencies and compatibility constraints. In such cases, the package manager gathers all dependency information from all the projects in the workspace generating a single manifest file that combines the versions of all dependencies.
+
+Furthermore, workspaces can be "nested", meaning a project defining a workspace can also be part of another workspace. In this scenario, a single manifest file is still utilized, stored alongside the "root project" (the project that doesn't have another workspace including it). An example file structure could look like this:
+
+```
+Project.toml # projects = ["MyPackage"]
+Manifest.toml
+MyPackage/
+    Project.toml # projects = ["test"]
+    test/
+        Project.toml
+```
+
 ### [Package/Environment Preferences](@id preferences)
 
 Preferences are dictionaries of metadata that influence package behavior within an environment.
diff --git a/test/loading.jl b/test/loading.jl
index 8ba2cf3026120..872ccd197f0f8 100644
--- a/test/loading.jl
+++ b/test/loading.jl
@@ -1550,3 +1550,61 @@ end
     rot13proj = joinpath(@__DIR__, "project", "Rot13")
     @test readchomp(`$(Base.julia_cmd()) --startup-file=no --project=$rot13proj -m Rot13 --project nowhere ABJURER`) == "--cebwrpg abjurer NOWHERE "
 end
+
+@testset "workspace loading" begin
+   old_load_path = copy(LOAD_PATH)
+   try
+       empty!(LOAD_PATH)
+       push!(LOAD_PATH, joinpath(@__DIR__, "project", "SubProject"))
+       @test Base.get_preferences()["value"] == 1
+       @test Base.get_preferences()["x"] == 1
+
+       empty!(LOAD_PATH)
+       push!(LOAD_PATH, joinpath(@__DIR__, "project", "SubProject", "sub"))
+       id = Base.identify_package("Devved")
+       @test isfile(Base.locate_package(id))
+       @test Base.identify_package("Devved2") === nothing
+       id3 = Base.identify_package("MyPkg")
+       @test isfile(Base.locate_package(id3))
+
+       empty!(LOAD_PATH)
+       push!(LOAD_PATH, joinpath(@__DIR__, "project", "SubProject", "PackageThatIsSub"))
+       id_pkg = Base.identify_package("PackageThatIsSub")
+       @test Base.identify_package(id_pkg, "Devved") === nothing
+       id_dev2 = Base.identify_package(id_pkg, "Devved2")
+       @test isfile(Base.locate_package(id_dev2))
+       id_mypkg = Base.identify_package("MyPkg")
+       @test isfile(Base.locate_package(id_mypkg))
+       id_dev = Base.identify_package(id_mypkg, "Devved")
+       @test isfile(Base.locate_package(id_dev))
+       @test Base.get_preferences()["value"] == 2
+       @test Base.get_preferences()["x"] == 1
+       @test Base.get_preferences()["y"] == 2
+
+       empty!(LOAD_PATH)
+       push!(LOAD_PATH, joinpath(@__DIR__, "project", "SubProject", "PackageThatIsSub", "test"))
+       id_pkg = Base.identify_package("PackageThatIsSub")
+       @test isfile(Base.locate_package(id_pkg))
+       @test Base.identify_package(id_pkg, "Devved") === nothing
+       id_dev2 = Base.identify_package(id_pkg, "Devved2")
+       @test isfile(Base.locate_package(id_dev2))
+       id_mypkg = Base.identify_package("MyPkg")
+       @test isfile(Base.locate_package(id_mypkg))
+       id_dev = Base.identify_package(id_mypkg, "Devved")
+       @test isfile(Base.locate_package(id_dev))
+       @test Base.get_preferences()["value"] == 3
+       @test Base.get_preferences()["x"] == 1
+       @test Base.get_preferences()["y"] == 2
+       @test Base.get_preferences()["z"] == 3
+
+       empty!(LOAD_PATH)
+       push!(LOAD_PATH, joinpath(@__DIR__, "project", "SubProject", "test"))
+       id_mypkg = Base.identify_package("MyPkg")
+       id_dev = Base.identify_package(id_mypkg, "Devved")
+       @test isfile(Base.locate_package(id_dev))
+       @test Base.identify_package("Devved2") === nothing
+
+    finally
+       copy!(LOAD_PATH, old_load_path)
+   end
+end
diff --git a/test/project/SubProject/Devved/Project.toml b/test/project/SubProject/Devved/Project.toml
new file mode 100644
index 0000000000000..63088a132cb77
--- /dev/null
+++ b/test/project/SubProject/Devved/Project.toml
@@ -0,0 +1,3 @@
+name = "Devved"
+uuid = "cbce3a6e-7a3d-4e84-8e6d-b87208df7599"
+version = "0.1.0"
diff --git a/test/project/SubProject/Devved/src/Devved.jl b/test/project/SubProject/Devved/src/Devved.jl
new file mode 100644
index 0000000000000..f3eb267409ece
--- /dev/null
+++ b/test/project/SubProject/Devved/src/Devved.jl
@@ -0,0 +1,5 @@
+module Devved
+
+greet() = print("Hello World!")
+
+end # module Devved
diff --git a/test/project/SubProject/Devved2/Project.toml b/test/project/SubProject/Devved2/Project.toml
new file mode 100644
index 0000000000000..c761630566116
--- /dev/null
+++ b/test/project/SubProject/Devved2/Project.toml
@@ -0,0 +1,3 @@
+name = "Devved2"
+uuid = "08f74b90-50f5-462f-80b9-a72b1258a17b"
+version = "0.1.0"
diff --git a/test/project/SubProject/Devved2/src/Devved2.jl b/test/project/SubProject/Devved2/src/Devved2.jl
new file mode 100644
index 0000000000000..9bd5df2793671
--- /dev/null
+++ b/test/project/SubProject/Devved2/src/Devved2.jl
@@ -0,0 +1,5 @@
+module Devved2
+
+greet() = print("Hello World!")
+
+end # module Devved2
diff --git a/test/project/SubProject/Manifest.toml b/test/project/SubProject/Manifest.toml
new file mode 100644
index 0000000000000..5d791a74652d4
--- /dev/null
+++ b/test/project/SubProject/Manifest.toml
@@ -0,0 +1,68 @@
+# This file is machine-generated - editing it directly is not advised
+
+julia_version = "1.12.0-DEV"
+manifest_format = "2.0"
+project_hash = "620b9377bc807ff657e6618c8ccc24887eb40285"
+
+[[deps.Base64]]
+uuid = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"
+version = "1.11.0"
+
+[[deps.Devved]]
+path = "Devved"
+uuid = "cbce3a6e-7a3d-4e84-8e6d-b87208df7599"
+version = "0.1.0"
+
+[[deps.Devved2]]
+path = "Devved2"
+uuid = "08f74b90-50f5-462f-80b9-a72b1258a17b"
+version = "0.1.0"
+
+[[deps.InteractiveUtils]]
+deps = ["Markdown"]
+uuid = "b77e0a4c-d291-57a0-90e8-8db25a27a240"
+version = "1.11.0"
+
+[[deps.Logging]]
+deps = ["StyledStrings"]
+uuid = "56ddb016-857b-54e1-b83d-db4d58db5568"
+version = "1.11.0"
+
+[[deps.Markdown]]
+deps = ["Base64"]
+uuid = "d6f4376e-aef5-505a-96c1-9c027394607a"
+version = "1.11.0"
+
+[[deps.MyPkg]]
+deps = ["Devved", "Devved2"]
+path = "."
+uuid = "0cafdeb2-d7a2-40d0-8d22-4411fcc2c4ee"
+version = "0.0.0"
+
+[[deps.PackageThatIsSub]]
+deps = ["Devved2", "MyPkg"]
+path = "PackageThatIsSub"
+uuid = "1efb588c-9412-4e40-90a4-710420bd84aa"
+version = "0.1.0"
+
+[[deps.Random]]
+deps = ["SHA"]
+uuid = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
+version = "1.11.0"
+
+[[deps.SHA]]
+uuid = "ea8e919c-243c-51af-8825-aaa63cd721ce"
+version = "0.7.0"
+
+[[deps.Serialization]]
+uuid = "9e88b42a-f829-5b0c-bbe9-9e923198166b"
+version = "1.11.0"
+
+[[deps.StyledStrings]]
+uuid = "f489334b-da3d-4c2e-b8f0-e476e12c162b"
+version = "1.11.0"
+
+[[deps.Test]]
+deps = ["InteractiveUtils", "Logging", "Random", "Serialization"]
+uuid = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+version = "1.11.0"
diff --git a/test/project/SubProject/PackageThatIsSub/Project.toml b/test/project/SubProject/PackageThatIsSub/Project.toml
new file mode 100644
index 0000000000000..e41dd998c5a1c
--- /dev/null
+++ b/test/project/SubProject/PackageThatIsSub/Project.toml
@@ -0,0 +1,14 @@
+name = "PackageThatIsSub"
+uuid = "1efb588c-9412-4e40-90a4-710420bd84aa"
+version = "0.1.0"
+
+[workspace]
+projects = ["test"]
+
+[deps]
+Devved2 = "08f74b90-50f5-462f-80b9-a72b1258a17b"
+MyPkg = "0cafdeb2-d7a2-40d0-8d22-4411fcc2c4ee"
+
+[preferences]
+value = 2
+y = 2
diff --git a/test/project/SubProject/PackageThatIsSub/src/PackageThatIsSub.jl b/test/project/SubProject/PackageThatIsSub/src/PackageThatIsSub.jl
new file mode 100644
index 0000000000000..7f9ea94ccb156
--- /dev/null
+++ b/test/project/SubProject/PackageThatIsSub/src/PackageThatIsSub.jl
@@ -0,0 +1,5 @@
+module PackageThatIsSub
+
+greet() = print("Hello World!")
+
+end # module PackageThatIsSub
diff --git a/test/project/SubProject/PackageThatIsSub/test/Project.toml b/test/project/SubProject/PackageThatIsSub/test/Project.toml
new file mode 100644
index 0000000000000..dc8186e2b735e
--- /dev/null
+++ b/test/project/SubProject/PackageThatIsSub/test/Project.toml
@@ -0,0 +1,8 @@
+[deps]
+MyPkg = "0cafdeb2-d7a2-40d0-8d22-4411fcc2c4ee"
+PackageThatIsSub = "1efb588c-9412-4e40-90a4-710420bd84aa"
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+
+[preferences]
+value = 3
+z = 3
diff --git a/test/project/SubProject/Project.toml b/test/project/SubProject/Project.toml
new file mode 100644
index 0000000000000..dcb84d865ac85
--- /dev/null
+++ b/test/project/SubProject/Project.toml
@@ -0,0 +1,13 @@
+name = "MyPkg"
+uuid = "0cafdeb2-d7a2-40d0-8d22-4411fcc2c4ee"
+
+[workspace]
+projects = ["sub", "PackageThatIsSub", "test"]
+
+[deps]
+Devved = "cbce3a6e-7a3d-4e84-8e6d-b87208df7599"
+Devved2 = "08f74b90-50f5-462f-80b9-a72b1258a17b"
+
+[preferences]
+value = 1
+x = 1
diff --git a/test/project/SubProject/src/MyPkg.jl b/test/project/SubProject/src/MyPkg.jl
new file mode 100644
index 0000000000000..6d84954645d55
--- /dev/null
+++ b/test/project/SubProject/src/MyPkg.jl
@@ -0,0 +1,3 @@
+module MyPkg
+
+end
diff --git a/test/project/SubProject/sub/Project.toml b/test/project/SubProject/sub/Project.toml
new file mode 100644
index 0000000000000..50aa238e91d57
--- /dev/null
+++ b/test/project/SubProject/sub/Project.toml
@@ -0,0 +1,3 @@
+[deps]
+Devved = "cbce3a6e-7a3d-4e84-8e6d-b87208df7599"
+MyPkg = "0cafdeb2-d7a2-40d0-8d22-4411fcc2c4ee"
diff --git a/test/project/SubProject/test/Project.toml b/test/project/SubProject/test/Project.toml
new file mode 100644
index 0000000000000..b64312e4b1ee2
--- /dev/null
+++ b/test/project/SubProject/test/Project.toml
@@ -0,0 +1,4 @@
+[deps]
+MyPkg = "0cafdeb2-d7a2-40d0-8d22-4411fcc2c4ee"
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+Devved = "cbce3a6e-7a3d-4e84-8e6d-b87208df7599"