diff --git a/documentation/project-layout.md b/documentation/project-layout.md
index ec652e3..ae336e3 100644
--- a/documentation/project-layout.md
+++ b/documentation/project-layout.md
@@ -98,8 +98,8 @@ spikeforge/
     cli.py                   save / list / compare CLI (spikeforge-benchmark)
     __main__.py              python -m spikeforge.benchmark
   observability/             Opt-in structured logging + metrics
-    logging_setup.py         configure_logging / reset_logging (reversible)
-    json_formatter.py        JsonFormatter: one JSON object per log line
+    logging_setup.py         configure_logging / reset_logging (reversible);
+                             JSON shape via capsize_commons.logging.JsonFormatter
     registry.py              MetricsRegistry: counters/gauges/timers
     timer.py                 Context-manager timer recording into a registry
     metrics.py               Shared registry + snapshot/JSON helpers
diff --git a/packages/spikeforge/pyproject.toml b/packages/spikeforge/pyproject.toml
index c7d4f34..f3bbafc 100644
--- a/packages/spikeforge/pyproject.toml
+++ b/packages/spikeforge/pyproject.toml
@@ -56,6 +56,10 @@ classifiers = [
     "Typing :: Typed",
 ]
 dependencies = [
+    # Shared §14 JSON logging. Logging is part of the capsize-commons base
+    # install — 0.1.1 defines no separate "logging" extra — so the dependency
+    # carries no bracket.
+    "capsize-commons>=0.1.1",
     "torch>=2.5",
     "torchvision>=0.20",
     "snntorch>=1.0",
diff --git a/spikeforge/__init__.py b/spikeforge/__init__.py
index befadc9..6da94e2 100644
--- a/spikeforge/__init__.py
+++ b/spikeforge/__init__.py
@@ -6,19 +6,33 @@
 older, narrower helper that loads an MNIST subset and rate-codes it -- it
 backs the tutorial demo and the animation walkthroughs, and it is not the
 class to reach for when training a network.
+
+The ML exports are resolved on first access (PEP 562) rather than at import
+time, so ``import spikeforge`` no longer pulls ``torch`` / ``snntorch`` /
+``torchvision``. That is what lets the non-ML surfaces —
+``spikeforge.observability`` and ``spikeforge.config`` — be imported and
+tested without the ML stack. ``from spikeforge import TrainingEngine`` and the
+attribute names below are unchanged.
 """
 
-from spikeforge.encoding.delta_trainer import DeltaTrainer
-from spikeforge.encoding.latency_trainer import (
-    LatencyTrainer,
-    convert_to_time,
-)
-from spikeforge.encoding.random_spikegen import RandomSpikeGenerator
-from spikeforge.training.logger import SNNTrainerLogger
-from spikeforge.training.trainer import SNNTrainer
-from spikeforge.training.training_engine import TrainingEngine
+from __future__ import annotations
+
+from importlib import import_module
+from typing import TYPE_CHECKING, Any
+
 from spikeforge.version import __version__
 
+if TYPE_CHECKING:
+    from spikeforge.encoding.delta_trainer import DeltaTrainer
+    from spikeforge.encoding.latency_trainer import (
+        LatencyTrainer,
+        convert_to_time,
+    )
+    from spikeforge.encoding.random_spikegen import RandomSpikeGenerator
+    from spikeforge.training.logger import SNNTrainerLogger
+    from spikeforge.training.trainer import SNNTrainer
+    from spikeforge.training.training_engine import TrainingEngine
+
 __all__ = [
     "__version__",
     "TrainingEngine",
@@ -29,3 +43,27 @@ class to reach for when training a network.
     "RandomSpikeGenerator",
     "convert_to_time",
 ]
+
+#: Public export -> defining module, resolved on first attribute access.
+_EXPORTS = {
+    "DeltaTrainer": "spikeforge.encoding.delta_trainer",
+    "LatencyTrainer": "spikeforge.encoding.latency_trainer",
+    "convert_to_time": "spikeforge.encoding.latency_trainer",
+    "RandomSpikeGenerator": "spikeforge.encoding.random_spikegen",
+    "SNNTrainerLogger": "spikeforge.training.logger",
+    "SNNTrainer": "spikeforge.training.trainer",
+    "TrainingEngine": "spikeforge.training.training_engine",
+}
+
+
+def __getattr__(name: str) -> Any:
+    """Resolve a public ML export on first access (PEP 562)."""
+    try:
+        module_name = _EXPORTS[name]
+    except KeyError:
+        raise AttributeError(
+            f"module {__name__!r} has no attribute {name!r}"
+        ) from None
+    value = getattr(import_module(module_name), name)
+    globals()[name] = value
+    return value
diff --git a/spikeforge/observability/__init__.py b/spikeforge/observability/__init__.py
index 11c69e0..d060834 100644
--- a/spikeforge/observability/__init__.py
+++ b/spikeforge/observability/__init__.py
@@ -5,9 +5,19 @@
 ``force=True``), and the metrics registry is a plain in-process object whose
 :meth:`~spikeforge.observability.registry.MetricsRegistry.snapshot`
 returns JSON-able data for the dashboard.
+
+``metrics`` / ``persistence`` / ``prometheus`` are resolved on first access
+(PEP 562) instead of at import time, so the logging surface — and the
+:class:`~spikeforge.observability.logging_setup.configure_logging` entry point
+that uses the shared ``capsize_commons`` formatter — is importable without
+dragging in the metrics stack.
 """
 
-from spikeforge.observability import metrics, persistence, prometheus
+from __future__ import annotations
+
+from importlib import import_module
+from typing import TYPE_CHECKING, Any
+
 from spikeforge.observability.logging_setup import (
     configure_logging,
     logging_enabled,
@@ -15,6 +25,9 @@
 )
 from spikeforge.observability.registry import MetricsRegistry
 
+if TYPE_CHECKING:
+    from spikeforge.observability import metrics, persistence, prometheus
+
 __all__ = [
     "MetricsRegistry",
     "configure_logging",
@@ -24,3 +37,23 @@
     "prometheus",
     "reset_logging",
 ]
+
+#: Submodule name -> import path, resolved on first attribute access.
+_LAZY_SUBMODULES = {
+    "metrics": "spikeforge.observability.metrics",
+    "persistence": "spikeforge.observability.persistence",
+    "prometheus": "spikeforge.observability.prometheus",
+}
+
+
+def __getattr__(name: str) -> Any:
+    """Import a lazier observability submodule on first access (PEP 562)."""
+    try:
+        module_name = _LAZY_SUBMODULES[name]
+    except KeyError:
+        raise AttributeError(
+            f"module {__name__!r} has no attribute {name!r}"
+        ) from None
+    module = import_module(module_name)
+    globals()[name] = module
+    return module
diff --git a/spikeforge/observability/json_formatter.py b/spikeforge/observability/json_formatter.py
deleted file mode 100644
index 30520a9..0000000
--- a/spikeforge/observability/json_formatter.py
+++ /dev/null
@@ -1,36 +0,0 @@
-"""A logging formatter that renders each record as one JSON line."""
-
-import json
-import logging
-from datetime import datetime, timezone
-from typing import Any, Dict
-
-#: Record attributes copied into the payload when the caller supplies them.
-_IDENTIFIERS = ("run_id", "config_id", "config_hash")
-
-
-class JsonFormatter(logging.Formatter):
-    """Format a log record as a single JSON object on one line."""
-
-    def format(self, record: logging.LogRecord) -> str:
-        """Return the record as compact, parseable JSON."""
-        return json.dumps(self._payload(record), default=str)
-
-    def _payload(self, record: logging.LogRecord) -> Dict[str, Any]:
-        """Assemble the timestamp/level/event and identifier fields."""
-        payload: Dict[str, Any] = {
-            "timestamp": datetime.fromtimestamp(
-                record.created, timezone.utc
-            ).isoformat(),
-            "level": record.levelname,
-            "event": record.getMessage(),
-            "logger": record.name,
-        }
-        for key in _IDENTIFIERS:
-            value = getattr(record, key, None)
-            if value is not None:
-                payload[key] = value
-        fields = getattr(record, "fields", None)
-        if fields:
-            payload["fields"] = fields
-        return payload
diff --git a/spikeforge/observability/logging_setup.py b/spikeforge/observability/logging_setup.py
index 7f6660a..7a0f585 100644
--- a/spikeforge/observability/logging_setup.py
+++ b/spikeforge/observability/logging_setup.py
@@ -12,7 +12,10 @@
 import os
 from typing import Any, Optional, Tuple
 
-from spikeforge.observability.json_formatter import JsonFormatter
+# The §14 JSON shape is owned by capsize-commons. ``message_key`` and
+# ``identifier_fields`` reproduce spikeforge's established payload — the
+# ``event`` key plus the three correlation fields — without a private copy.
+from capsize_commons.logging import JsonFormatter
 
 #: Package logger structured logging attaches to (never the root logger).
 LOGGER_NAME = "spikeforge"
@@ -21,6 +24,9 @@
 #: Values that turn an environment flag off.
 _FALSEY = ("", "0", "false", "no", "off")
 _HUMAN_FORMAT = "%(asctime)s %(levelname)s %(name)s %(message)s"
+#: Field names preserving spikeforge's JSON payload shape (see module note).
+_MESSAGE_KEY = "event"
+_IDENTIFIER_FIELDS = ("run_id", "config_id", "config_hash")
 
 _logger = logging.getLogger(LOGGER_NAME)
 _handler: Optional[logging.Handler] = None
@@ -51,7 +57,11 @@ def _handler_for(use_json: bool, stream: Any) -> logging.Handler:
     """Return a stream handler carrying the JSON or human formatter."""
     handler = logging.StreamHandler(stream)
     formatter = (
-        JsonFormatter() if use_json else logging.Formatter(_HUMAN_FORMAT)
+        JsonFormatter(
+            message_key=_MESSAGE_KEY, identifier_fields=_IDENTIFIER_FIELDS
+        )
+        if use_json
+        else logging.Formatter(_HUMAN_FORMAT)
     )
     handler.setFormatter(formatter)
     return handler
diff --git a/tests/test_packaging_profiles.py b/tests/test_packaging_profiles.py
index ec1e97c..7dc94fb 100644
--- a/tests/test_packaging_profiles.py
+++ b/tests/test_packaging_profiles.py
@@ -41,6 +41,7 @@
     "docs",
 }
 _EXPECTED_CORE_DEPS = {
+    "capsize-commons>=0.1.1",
     "torch>=2.5",
     "torchvision>=0.20",
     "snntorch>=1.0",