diff --git a/README.md b/README.md
index 917c588..afef92c 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 Device manifests for the A-Team Jenkins build pipelines.
 
-Each build job clones this repo, drops one device XML into `.repo/local_manifests/` of a warm source tree, syncs only the projects listed in it, and reads the device info from its annotations.
+Each base branch has one Jenkins job (named after the branch) running the shared `Jenkinsfile` from `main`. It rolls the base's warm source tree back to `@warm`, drops one device XML into `.repo/local_manifests/`, syncs only the projects listed in it, reads the device info from its annotations and the base settings from the branch's `build.toml`.
 
 ## Layout
 
@@ -85,8 +85,16 @@ plus a `.sha256` for each, e.g. `OFRP-12.1_A-Team_genevn_XT2315-261009.zip`.
    ```
 2. Copy an existing XML to `<codename>.xml` and edit the projects and annotations.
 3. Commit and push.
-4. Create the Jenkins job (`<RECOVERY>-<codename>`, e.g. `OFRP-genevn`) pointing at the branch and file.
+4. That's it: the branch's Jenkins job (named after the branch, e.g. `ofrp-12.1`) lists the new XML in its
+   `DEVICE` dropdown, and the portal picks it up on its next device sync.
 
 ## Adding a base
 
-Create a new branch named `<base>-<version>` (e.g. `shrp-12.1`) and add a device XML for each device built on it. Each base has its own copy of a device's XML, so update model or name changes on every branch that has that device.
+1. Create a new branch named `<base>-<version>` (e.g. `shrp-12.1`) and add a device XML for each device built on it.
+   Each base has its own copy of a device's XML, so update model or name changes on every branch that has that device.
+2. Add a `build.toml` (see the README on `main`) describing the base: portal project, release naming, ZFS dataset,
+   lunch target and release files.
+3. Prepare the warm source tree on buildBox and snapshot it as `<dataset>@warm`.
+4. Create a Jenkins job named exactly like the branch, using *Pipeline script from SCM* on `build_manifests`
+   branch `main`, script path `Jenkinsfile`.
+5. Map the portal project to the job in the portal admin.
diff --git a/build.toml b/build.toml
new file mode 100644
index 0000000..76a9b8f
--- /dev/null
+++ b/build.toml
@@ -0,0 +1,32 @@
+# Build settings for the ofrp-12.1 base, read by the shared Jenkinsfile on main.
+# Data only: unknown keys or wrong types stop the build.
+
+[base]
+project      = "orangefox"           # portal project slug
+project_name = "OrangeFox"
+version      = "R12.1"               # version shown in the portal
+release_tag  = "OFRP"                # <release_tag>-<release_ver>_A-Team_<codename>_<model>-<YYMMDD>
+release_ver  = "12.1"
+source_root  = "/build/ofox-12.1"    # mountpoint of zfs_dataset; out/ lives inside it
+zfs_dataset  = "build/ofox-12.1"     # rolled back to @warm before and after every build
+warm_check   = ["vendor/recovery"]   # must exist in the warm base
+lunch_target = "twrp_{codename}-eng"
+make_extra   = ["adbd"]              # built together with the ateam.partition target
+changelog    = "Automated OrangeFox testing build."
+
+[base.env]                           # extra environment for lunch and the build
+FOX_BUILD_DEVICE = "{codename}"      # everything else (OF_* / FOX_*) comes from the tree's OFRP.mk
+
+# Release files, picked from out/target/product/<codename>/ (exactly one match each)
+[outputs.img]
+glob     = "OrangeFox-*.img"
+checksum = "md5"                     # native sidecar to verify: md5 | sha256 | none
+
+[outputs.zip]
+glob     = "OrangeFox-*.zip"
+checksum = "md5"
+test_zip = true
+
+# Per-device overrides (lunch_target, make_extra, env, outputs), for example:
+# [devices.sycamore_row_5G]
+# lunch_target = "twrp_sycamore_row_5G-eng"