diff --git a/src/dspeed/processors/__init__.py b/src/dspeed/processors/__init__.py
index 26644d7..971acc4 100644
--- a/src/dspeed/processors/__init__.py
+++ b/src/dspeed/processors/__init__.py
@@ -97,6 +97,7 @@
 from .optimize import optimize_1pz, optimize_2pz
 from .param_lookup import param_lookup
 from .peak_snr_threshold import peak_snr_threshold
+from .pmt_pulse_injector import inject_general_logistic, inject_gumbel
 from .pole_zero import double_pole_zero, pole_zero
 from .poly_fit import poly_diff, poly_exp_rms, poly_fit
 from .presum import presum
@@ -193,4 +194,6 @@
     "classification_layer_no_bias",
     "classification_layer_with_bias",
     "normalisation_layer",
+    "inject_general_logistic",
+    "inject_gumbel",
 ]
diff --git a/src/dspeed/processors/pmt_pulse_injector.py b/src/dspeed/processors/pmt_pulse_injector.py
new file mode 100644
index 0000000..7c875f6
--- /dev/null
+++ b/src/dspeed/processors/pmt_pulse_injector.py
@@ -0,0 +1,123 @@
+from __future__ import annotations
+
+import numpy as np
+from numba import guvectorize
+
+from ..utils import numba_defaults_kwargs as nb_kwargs
+
+
+@guvectorize(
+    [
+        "void(float32[:], float32, float32, float32, float32[:])",
+        "void(float64[:], float64, float64, float64, float64[:])",
+    ],
+    "(n),(),(),()->(n)",
+    **nb_kwargs,
+)
+def inject_gumbel(
+    wf_in: np.ndarray, a: float, t0: float, beta: float, wf_out: np.ndarray
+) -> None:
+    """
+    Injects a Gumbel distribution into the waveform `wf_in`, modifying it in place in `wf_out`.
+
+    Parameters:
+    - wf_in: Input waveform (1D array).
+    - a: Amplitude of the Gumbel distribution.
+    - t0: Temporal centroid of the Gumbel distribution.
+    - beta: Scale parameter (controls spread of the Gumbel distribution).
+    - wf_out: Output waveform (1D array), modified by adding the Gumbel distribution.
+    """
+
+    wf_out[:] = np.nan
+
+    # Early exit if any of the inputs contain NaN values (invalid inputs).
+    if np.isnan(wf_in).any() or np.isnan(a) or np.isnan(t0) or np.isnan(beta):
+        return
+
+    wf_out[:] = wf_in[:]
+
+    # Define the range of indices over which the Gumbel distribution will be applied.
+    # Start injecting the distribution at 2 beta below the centroid (t0).
+    start = t0
+    mu = t0 + (2 * beta)
+    end = mu + (8 * beta)
+
+    # Ensure the range is within valid waveform boundaries.
+    if start < 0:
+        start = 0
+    if end > len(wf_in):
+        end = len(wf_in)
+
+    # Loop through the specified range and add the Gumbel distribution to wf_out.
+    for i in range(start, end):
+
+        z = (i - mu) / beta
+        wf_out[i] += (a / beta) * np.exp(-(z + np.exp(-z)))
+
+
+@guvectorize(
+    [
+        "void(float32[:], float32, float32, float32, float32, float32, float32, float32[:])",
+        "void(float64[:], float64, float64, float64, float64, float64, float64, float64[:])",
+    ],
+    "(n),(),(),(),(),(),()->(n)",
+    **nb_kwargs,
+)
+def inject_general_logistic(
+    wf_in: np.ndarray,
+    a: float,
+    t0: float,
+    rt: float,
+    q: float,
+    v: float,
+    decay: float,
+    wf_out: np.ndarray,
+) -> None:
+    r"""Inject sigmoid pulse into existing waveform to simulate pileup.
+
+    .. math::
+
+        s(t) = \frac{A}{(1 + q \exp[-4 \log(99) (t - t_0 - t_r/2) / t_r])^{1/v}}
+                e^{-(t-t_0)/\tau}
+
+    Parameters
+    ----------
+    wf_in
+        the input waveform.
+    a
+        the amplitude :math:`A` of the injected waveform.
+    t0
+        the position :math:`t_0` of the injected waveform.
+    rt
+        the rise time :math:`t_r` of the injected waveform.
+    q
+        shaping parameter of the logistic function.
+    v
+        shaping parameter of the logistic function.
+    decay
+        the decay parameter :math:`\tau` of the injected waveform.
+    wf_out
+        the output waveform.
+    """
+
+    wf_out[:] = np.nan
+
+    # Early exit if any of the inputs contain NaN values (invalid inputs).
+    if (
+        np.isnan(wf_in).any()
+        or np.isnan(a)
+        or np.isnan(t0)
+        or np.isnan(rt)
+        or np.isnan(q)
+        or np.isnan(v)
+        or np.isnan(decay)
+    ):
+        return
+
+    wf_out[:] = wf_in[:]
+    rise = 4 * np.log(99) / rt
+
+    for t in range(len(wf_out)):
+        wf_out[t] = wf_out[t] + a / (
+            (1 + q * np.exp(-rise * (t - t0 - rt / 2))) ** (1 / v)
+        ) * np.exp(-(1 / decay) * (t - t0))