refactor(runtime): split operator runtime into per-language crates

.claude/skills/adora-project/SKILL.md

@@ -181,7 +181,7 @@ Uses `goal_id` and `goal_status` metadata keys. Supports cancellation.
 cargo build --all --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python
 
 # Test (exclude Python + examples)
-cargo test --all --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python --exclude dora-cli-api-python --exclude dora-examples
+cargo test --all --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python --exclude dora-runtime-python --exclude dora-cli-api-python --exclude dora-examples
 
 # Single crate
 cargo test -p dora-core

.github/workflows/cargo-release.yml

@@ -110,7 +110,11 @@ jobs:
           publish_if_not_exists dora-coordinator
           publish_if_not_exists dora-daemon
           publish_if_not_exists dora-operator-api-python
-          publish_if_not_exists dora-runtime
+          # The former `dora-runtime`, split per language. `dora-cli` depends on
+          # `dora-runtime-shared-lib` (→ `-api`), so both must land first.
+          publish_if_not_exists dora-runtime-api
+          publish_if_not_exists dora-runtime-shared-lib
+          publish_if_not_exists dora-runtime-python
           publish_if_not_exists dora-cli
 
           # Publish ROS2 bridge (before the cxx APIs, which optionally

.github/workflows/ci.yml

@@ -177,7 +177,7 @@ jobs:
       - name: Check examples compile
         run: cargo check --examples
       # ...nor does it build test targets, so the `#[cfg(test)]` modules of
-      # the three PyO3 crates were type-checked nowhere: they're excluded
+      # the PyO3 crates were type-checked nowhere: they're excluded
       # from `cargo test` (see the `test` job) and from clippy above, and
       # `cargo check --all` only covers their lib targets. A syntax error in
       # one of those test modules could ship. This is rmeta-only and `Check`
@@ -189,6 +189,7 @@ jobs:
           -p dora-node-api-python
           -p dora-operator-api-python
           -p dora-ros2-bridge-python
+          -p dora-runtime-python
 
   test:
     # Linux-only on PR CI (#1716). macOS + Windows coverage runs in nightly.
@@ -239,13 +240,16 @@ jobs:
       # The PyO3 crates stay excluded here — their test binaries link
       # libpython, and this job sets up no interpreter. Their unit tests run
       # in `contract-tests`, which does; keep that step in sync if this list
-      # changes.
+      # changes. `dora-runtime-python` is one of them: it links pyo3 like the
+      # rest, and only its own targets are skipped — the lib still builds
+      # above, as a dependency of dora-cli-api-python.
       - name: Test
         run: >
           cargo test --all
           --exclude dora-node-api-python
           --exclude dora-operator-api-python
           --exclude dora-ros2-bridge-python
+          --exclude dora-runtime-python
           --exclude dora-cli-api-python
           --exclude dora-examples
 

.github/workflows/nightly.yml

@@ -1207,6 +1207,7 @@ jobs:
           --exclude dora-node-api-python
           --exclude dora-operator-api-python
           --exclude dora-ros2-bridge-python
+          --exclude dora-runtime-python
           --exclude dora-cli-api-python
           --exclude dora-examples
 
@@ -1847,6 +1848,7 @@ jobs:
           --exclude dora-node-api-python
           --exclude dora-operator-api-python
           --exclude dora-ros2-bridge-python
+          --exclude dora-runtime-python
           --exclude dora-cli-api-python
       - name: Check (cross)
         if: matrix.cross
@@ -1855,6 +1857,7 @@ jobs:
           --exclude dora-node-api-python
           --exclude dora-operator-api-python
           --exclude dora-ros2-bridge-python
+          --exclude dora-runtime-python
           --exclude dora-cli-api-python
 
   # ===== ROS2 bridge basic checks =====

.github/workflows/release.yml

@@ -86,7 +86,9 @@ jobs:
             dora-coordinator
             dora-daemon
             dora-operator-api-python
-            dora-runtime
+            dora-runtime-api
+            dora-runtime-shared-lib
+            dora-runtime-python
             dora-cli
             dora-ros2-bridge-msg-gen
             dora-ros2-bridge

.pr-bodies/2777.md

@@ -0,0 +1,15 @@
+Splits the monolithic `dora-runtime` into a language-neutral SDK plus per-language backend crates, and table-drives the daemon's runtime spawn logic. Behavior-preserving — no descriptor/YAML changes.
+
+- `dora-runtime-api` — the SDK: operator event loop, node harness, `RuntimeHandle`, and the `OperatorRunner` backend trait + `main(runner)` entry.
+- `dora-runtime-shared-lib` — libloading/C-ABI backend, shipped in the `dora` CLI (`dora runtime`).
+- `dora-runtime-python` — PyO3 backend, the only crate linking pyo3, shipped in the wheel (`dora.start_runtime()`).
+
+The `python` cargo feature and all `#[cfg(feature = "python")]` dispatch are gone; adding a language is now one crate implementing `OperatorRunner`. `dora-cli` no longer pulls pyo3 into its tree at all. The daemon's python/shared-library selection moves to `spawn/runtime_registry.rs`, keyed on the new `OperatorSource::runtime_name()` helper, reproducing the existing launch commands verbatim (incl. the #1797/#1805 fixes). The registry is the seam where a follow-up can add third-party runtimes via an explicit `runtimes:` map.
+
+`dora-runtime-python` also hosts shared-library operators, by delegating to `SharedLibRunner`. That arm is load-bearing: when the daemon is itself an embedded Python process (`current_exe` ends in `python`/`python3`), `native_runtime_command` routes *native* runtime nodes to `python -uc "import dora; dora.start_runtime()"`, and the pre-split `dora-runtime` served them because it compiled the shared-library backend in unconditionally.
+
+Publishing: both release workflows drop the now-gone `dora-runtime` for `dora-runtime-api` + `dora-runtime-shared-lib` + `dora-runtime-python`, ordered before `dora-cli` (which depends on the shared-lib backend).
+
+`dora-runtime-python` is excluded from `cargo test --all` alongside `dora-cli-api-python` — it is a plain rlib, so unlike the `extension-module` cdylibs its test binary links libpython, and the CI test job runs without `setup-python`. Its lib still builds there, as a dependency of `dora-cli-api-python`.
+
+Verified: `cargo test --all` (only the two known container-local `rmw_zenoh_pubsub` failures, which need multicast), `clippy --all -D warnings`, `fmt --check`, `cargo check --examples`, `make qa-fast`, and an end-to-end shared-library operator dataflow (daemon → runtime → dlopen'd operator → sink, all green).

AGENTS.md

@@ -38,7 +38,9 @@ Important packages:
 - `binaries/cli`: `dora` CLI
 - `binaries/daemon`: local process manager and transport bridge
 - `binaries/coordinator`: distributed orchestration
-- `binaries/runtime`: in-process operator runtime
+- `binaries/runtime-api`: language-neutral operator runtime SDK (`OperatorRunner` trait + event loop)
+- `binaries/runtime-shared-lib`: shared-library (C ABI) operator runtime backend (in the `dora` CLI)
+- `binaries/runtime-python`: Python (PyO3) operator runtime backend (in the Python wheel)
 - `libraries/core`: descriptor parsing and shared build/runtime utilities
 - `libraries/message`: protocol and message definitions
 - `apis/rust/node`: Rust node API
@@ -74,6 +76,7 @@ cargo test --all \
   --exclude dora-node-api-python \
   --exclude dora-operator-api-python \
   --exclude dora-ros2-bridge-python \
+  --exclude dora-runtime-python \
   --exclude dora-cli-api-python \
   --exclude dora-examples
 
@@ -153,6 +156,7 @@ cargo test --all \
   --exclude dora-node-api-python \
   --exclude dora-operator-api-python \
   --exclude dora-ros2-bridge-python \
+  --exclude dora-runtime-python \
   --exclude dora-cli-api-python \
   --exclude dora-examples
 ```

CLAUDE.md

@@ -20,7 +20,7 @@ cargo build -p dora-daemon
 cargo check --all
 
 # Test all (excluding Python)
-cargo test --all --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python
+cargo test --all --exclude dora-runtime-python --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python
 
 # Test single package
 cargo test -p dora-core
@@ -58,7 +58,9 @@ dora run examples/python-dataflow/dataflow.yml --uv --stop-after 10s
 | `binaries/cli` | dora-cli | CLI binary (`dora` command) - build, run, stop dataflows |
 | `binaries/daemon` | dora-daemon | Spawns nodes, manages local shared-memory/TCP communication |
 | `binaries/coordinator` | dora-coordinator | Orchestrates distributed multi-daemon deployments |
-| `binaries/runtime` | dora-runtime | In-process operator execution runtime |
+| `binaries/runtime-api` | dora-runtime-api | Language-neutral operator runtime SDK (event loop, node harness, `OperatorRunner` trait) |
+| `binaries/runtime-shared-lib` | dora-runtime-shared-lib | Shared-library (C ABI) operator runtime backend; shipped in the `dora` CLI (`dora runtime`) |
+| `binaries/runtime-python` | dora-runtime-python | Python (PyO3) operator runtime backend; shipped in the Python wheel (`dora.start_runtime()`) |
 | `libraries/message` | dora-message | All inter-component message types and protocol definitions |
 | `libraries/core` | dora-core | Dataflow descriptor parsing, build utilities, Zenoh config |
 | `apis/rust/node` | dora-node-api | Rust API for writing custom nodes |
@@ -133,6 +135,7 @@ cargo test --all \
   --exclude dora-node-api-python \
   --exclude dora-operator-api-python \
   --exclude dora-ros2-bridge-python \
+  --exclude dora-runtime-python \
   --exclude dora-cli-api-python \
   --exclude dora-examples
 
@@ -142,9 +145,10 @@ cargo test --all \
 cargo check --examples
 
 # 5. Only if you touched a PyO3 crate (apis/python/node, apis/python/operator,
-# libraries/extensions/ros2-bridge/python): their unit tests are excluded from
-# the `cargo test --all` above because the test binaries link libpython, so run
-# them explicitly. CI runs the same command in ci.yml's `contract-tests` job.
+# libraries/extensions/ros2-bridge/python, binaries/runtime-python): their unit
+# tests are excluded from the `cargo test --all` above because the test binaries
+# link libpython, so run them explicitly. CI runs the same command in ci.yml's
+# `contract-tests` job.
 make qa-test-python
 
 # Quick single-crate check while iterating:

CONTRIBUTING.md

@@ -17,7 +17,7 @@ Running a command for the whole workspace is possible by passing `--workspace`.
 cargo build --all --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python
 
 # Test all
-cargo test --all --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python
+cargo test --all --exclude dora-runtime-python --exclude dora-node-api-python --exclude dora-operator-api-python --exclude dora-ros2-bridge-python
 
 # Lint
 cargo clippy --all -- -D warnings

Cargo.toml

@@ -14,7 +14,9 @@ members = [
     "binaries/cli",
     "binaries/coordinator",
     "binaries/daemon",
-    "binaries/runtime",
+    "binaries/runtime-api",
+    "binaries/runtime-shared-lib",
+    "binaries/runtime-python",
     "binaries/mavlink2-bridge-node",
     "binaries/ros2-bridge-node",
     "examples/rust-dataflow/node",
@@ -123,7 +125,9 @@ dora-download = { version = "1.0.0-rc.4", path = "libraries/extensions/download"
 dora-log-utils = { version = "1.0.0-rc.4", path = "libraries/log-utils" }
 dora-coordinator-store = { version = "1.0.0-rc.4", path = "libraries/coordinator-store" }
 dora-cli = { version = "1.0.0-rc.4", path = "binaries/cli" }
-dora-runtime = { version = "1.0.0-rc.4", path = "binaries/runtime" }
+dora-runtime-api = { version = "1.0.0-rc.4", path = "binaries/runtime-api" }
+dora-runtime-shared-lib = { version = "1.0.0-rc.4", path = "binaries/runtime-shared-lib" }
+dora-runtime-python = { version = "1.0.0-rc.4", path = "binaries/runtime-python" }
 dora-daemon = { version = "1.0.0-rc.4", path = "binaries/daemon" }
 dora-coordinator = { version = "1.0.0-rc.4", path = "binaries/coordinator" }
 dora-ros2-bridge = { version = "1.0.0-rc.4", path = "libraries/extensions/ros2-bridge" }

Makefile

@@ -145,21 +145,29 @@ qa-test:
 		--exclude dora-node-api-python \
 		--exclude dora-operator-api-python \
 		--exclude dora-ros2-bridge-python \
+		--exclude dora-runtime-python \
 		--exclude dora-cli-api-python \
 		--exclude dora-examples
 
-# The unit tests of the three PyO3 crates `qa-test` excludes. Kept a separate
+# The unit tests of the PyO3 crates `qa-test` excludes. Kept a separate
 # target, not folded into `qa-test`: cargo builds these crates without
 # `pyo3/extension-module` (unlike the maturin wheel), so the test binaries
 # link libpython directly and need an interpreter >= 3.11 with a shared
 # library — a machine set up only for Rust work would start failing the
 # everyday gate. CI runs this same target in ci.yml's `contract-tests` job,
 # which sets Python up explicitly.
+#
+# `dora-runtime-python` is the operator runtime's Python backend. Its tests
+# cover the cross-language arms of the runtime split — above all that a
+# shared-library operator reaching the Python runtime is *delegated* to the
+# shared-lib backend rather than rejected, which is what keeps native
+# operators working under an embedded-Python daemon.
 qa-test-python:
 	@cargo test --lib \
 		-p dora-node-api-python \
 		-p dora-operator-api-python \
-		-p dora-ros2-bridge-python
+		-p dora-ros2-bridge-python \
+		-p dora-runtime-python
 
 qa-coverage:
 	@scripts/qa/coverage.sh

README.md

@@ -592,6 +592,7 @@ cargo build -p dora-cli
 ```bash
 # Run all tests
 cargo test --all \
+  --exclude dora-runtime-python \
   --exclude dora-node-api-python \
   --exclude dora-operator-api-python \
   --exclude dora-ros2-bridge-python

README.zh-CN.md

@@ -479,6 +479,7 @@ cargo build -p dora-cli
 ```bash
 # 运行所有测试
 cargo test --all \
+  --exclude dora-runtime-python \
   --exclude dora-node-api-python \
   --exclude dora-operator-api-python \
   --exclude dora-ros2-bridge-python

apis/python/cli/Cargo.toml

@@ -12,11 +12,11 @@ publish = false  # PyO3 cdylib, shipped via PyPI as `dora-rs-cli`, not crates.io
 
 [features]
 default = ["telemetry"]
-telemetry = ["dora-runtime/telemetry"]
+telemetry = ["dora-runtime-python/telemetry"]
 
 [dependencies]
 dora-cli = { workspace = true, features = ["python"] }
-dora-runtime = { workspace = true, features = ["tracing", "metrics", "python"] }
+dora-runtime-python = { workspace = true, features = ["tracing", "metrics"] }
 dora-download = { workspace = true }
 dora-node-api = { workspace = true }
 eyre = { workspace = true }

apis/python/cli/src/lib.rs

@@ -6,7 +6,7 @@ use pyo3::prelude::*;
 /// :rtype: None
 #[pyfunction]
 pub fn start_runtime() -> eyre::Result<()> {
-    dora_runtime::main().wrap_err("Dora Runtime raised an error.")
+    dora_runtime_python::main().wrap_err("Dora Runtime raised an error.")
 }
 
 /// Build a Dataflow, exactly the same way as `dora build` command line tool.

apis/python/node/Cargo.toml

@@ -22,7 +22,7 @@ async = ["pyo3/experimental-async"]
 dora-node-api = { workspace = true }
 dora-message = { workspace = true }
 dora-operator-api-python = { workspace = true }
-dora-runtime = { workspace = true, features = ["python"] }
+dora-runtime-python = { workspace = true }
 dora-cli = { workspace = true, features = ["python"] }
 chrono = { version = "0.4", features = ["serde"] }
 pyo3.workspace = true

apis/python/node/src/lib.rs

@@ -3884,7 +3884,7 @@ impl Node {
 /// :rtype: None
 #[pyfunction]
 pub fn start_runtime() -> eyre::Result<()> {
-    dora_runtime::main().wrap_err("Dora Runtime raised an error.")
+    dora_runtime_python::main().wrap_err("Dora Runtime raised an error.")
 }
 
 /// Build a Dataflow, exactly the same way as `dora build` command line tool.