diff --git a/Jlqcd.hpp b/Jlqcd.hpp
new file mode 100644
index 0000000..ffd5bb6
--- /dev/null
+++ b/Jlqcd.hpp
@@ -0,0 +1,206 @@
+/*
+ * Copyright (C) 2026
+ *
+ * Hadrons presets for the JLQCD scaled-domain-wall ensembles used by iblep.
+ */
+
+#pragma once
+
+#include <Hadrons/Application.hpp>
+#include <Hadrons/Modules.hpp>
+
+#include <array>
+#include <stdexcept>
+#include <string>
+#include <string_view>
+
+namespace hadpresets
+{
+using namespace Grid::Hadrons;
+
+struct Jlqcd
+{
+  struct EnsembleParameters
+  {
+    double ml, ms, M5, scale;
+    unsigned int L, T, Ls;
+  };
+
+  inline static constexpr EnsembleParameters fUd3SaPar{0.003, 0.015, 1., 2., 64, 128, 8};
+  inline static constexpr EnsembleParameters mUd3SaPar{0.0042, 0.025, 1., 2., 48, 96, 8};
+  inline static constexpr EnsembleParameters mUd3SbPar{0.0042, 0.018, 1., 2., 48, 96, 8};
+  inline static constexpr EnsembleParameters cUd2SaPar{0.0035, 0.040, 1., 2., 32, 64, 12};
+  inline static constexpr EnsembleParameters cUd2SaLPar{0.0035, 0.040, 1., 2., 48, 96, 12};
+  inline static constexpr EnsembleParameters cUd3SaPar{0.007, 0.040, 1., 2., 32, 64, 12};
+  inline static constexpr EnsembleParameters cUd3SbPar{0.007, 0.030, 1., 2., 32, 64, 12};
+  inline static constexpr EnsembleParameters testPar{0.010, 0.030, 1., 2., 8, 16, 8};
+
+  static inline const EnsembleParameters &ensemble(const std::string &name);
+
+  static inline void addMixedPrecisionSolver(Application &app, const EnsembleParameters &par,
+                                             const std::string &solverName,
+                                             const std::string &gaugeName, const double mass,
+                                             const std::string &twist,
+                                             const std::string &boundary = "1 1 1 -1",
+                                             const double residual = 1.0e-8);
+
+  static inline void addNoFailSolver(Application &app, const EnsembleParameters &par,
+                                     const std::string &solverName, const std::string &gaugeName,
+                                     const double mass, const std::string &twist,
+                                     const std::string &boundary = "1 1 1 -1",
+                                     const double residual = 1.0e-20);
+
+  static inline void addLightSolver(Application &app, const EnsembleParameters &par,
+                                    const std::string &solverName, const std::string &gaugeName,
+                                    const double mass, const std::string &twist,
+                                    const std::string &boundary = "1 1 1 -1",
+                                    const double residual = 1.0e-8);
+
+  static inline void addLightSolver(Application &app, const EnsembleParameters &par,
+                                    const std::string &solverName, const std::string &gaugeName,
+                                    const std::string &twist = "0. 0. 0. 0.",
+                                    const std::string &boundary = "1 1 1 -1",
+                                    const double residual = 1.0e-8);
+
+  static inline void addStrangeSolver(Application &app, const EnsembleParameters &par,
+                                      const std::string &solverName, const std::string &gaugeName,
+                                      const double mass, const std::string &twist,
+                                      const std::string &boundary = "1 1 1 -1",
+                                      const double residual = 1.0e-8);
+
+  static inline void addStrangeSolver(Application &app, const EnsembleParameters &par,
+                                      const std::string &solverName, const std::string &gaugeName,
+                                      const std::string &twist = "0. 0. 0. 0.",
+                                      const std::string &boundary = "1 1 1 -1",
+                                      const double residual = 1.0e-8);
+
+  static inline void addHeavySolver(Application &app, const EnsembleParameters &par,
+                                    const std::string &solverName, const std::string &gaugeName,
+                                    const double mass, const std::string &twist,
+                                    const std::string &boundary = "1 1 1 -1",
+                                    const double residual = 1.0e-20);
+};
+
+inline const Jlqcd::EnsembleParameters &Jlqcd::ensemble(const std::string &name)
+{
+  if (name == "fUd3Sa")
+    return fUd3SaPar;
+  if (name == "mUd3Sa")
+    return mUd3SaPar;
+  if (name == "mUd3Sb")
+    return mUd3SbPar;
+  if (name == "cUd2Sa")
+    return cUd2SaPar;
+  if (name == "cUd2SaL")
+    return cUd2SaLPar;
+  if (name == "cUd3Sa")
+    return cUd3SaPar;
+  if (name == "cUd3Sb")
+    return cUd3SbPar;
+  if (name == "test")
+    return testPar;
+
+  throw std::invalid_argument("unknown JLQCD ensemble preset '" + std::string(name) + "'");
+}
+
+inline void Jlqcd::addMixedPrecisionSolver(Application &app, const EnsembleParameters &par,
+                                           const std::string &solverName,
+                                           const std::string &gaugeName, const double mass,
+                                           const std::string &twist, const std::string &boundary,
+                                           const double residual)
+{
+  const std::string prefix = solverName;
+
+  MUtilities::GaugeSinglePrecisionCast::Par gaugeCastPar;
+  gaugeCastPar.field = gaugeName;
+  app.createModule<MUtilities::GaugeSinglePrecisionCast>(prefix + "_gauge_fp32", gaugeCastPar);
+
+  MAction::ScaledDWF::Par actionPar;
+  actionPar.gauge = gaugeName;
+  actionPar.Ls = par.Ls;
+  actionPar.M5 = par.M5;
+  actionPar.mass = mass;
+  actionPar.scale = par.scale;
+  actionPar.boundary = boundary;
+  actionPar.twist = twist;
+  app.createModule<MAction::ScaledDWF>(prefix + "_dwf", actionPar);
+
+  actionPar.gauge = prefix + "_gauge_fp32";
+  app.createModule<MAction::ScaledDWFF>(prefix + "_dwf_fp32", actionPar);
+
+  MSolver::MixedPrecisionRBPrecCG::Par solverPar;
+  solverPar.innerAction = prefix + "_dwf_fp32";
+  solverPar.outerAction = prefix + "_dwf";
+  solverPar.maxInnerIteration = 10000;
+  solverPar.maxOuterIteration = 100;
+  solverPar.residual = residual;
+  solverPar.innerGuesser = "";
+  solverPar.outerGuesser = "";
+  app.createModule<MSolver::MixedPrecisionRBPrecCG>(solverName, solverPar);
+}
+
+inline void Jlqcd::addNoFailSolver(Application &app, const EnsembleParameters &par,
+                                   const std::string &solverName, const std::string &gaugeName,
+                                   const double mass, const std::string &twist,
+                                   const std::string &boundary, const double residual)
+{
+  const std::string prefix = solverName;
+
+  MAction::ScaledDWF::Par actionPar;
+  actionPar.gauge = gaugeName;
+  actionPar.Ls = par.Ls;
+  actionPar.M5 = par.M5;
+  actionPar.mass = mass;
+  actionPar.scale = par.scale;
+  actionPar.boundary = boundary;
+  actionPar.twist = twist;
+  app.createModule<MAction::ScaledDWF>(prefix + "_dwf", actionPar);
+
+  MSolver::RBPrecCGNoFail::Par solverPar;
+  solverPar.action = prefix + "_dwf";
+  solverPar.maxIteration = 30000;
+  solverPar.residual = residual;
+  solverPar.guesser = "";
+  app.createModule<MSolver::RBPrecCGNoFail>(solverName, solverPar);
+}
+
+inline void Jlqcd::addLightSolver(Application &app, const EnsembleParameters &par,
+                                  const std::string &solverName, const std::string &gaugeName,
+                                  const double mass, const std::string &twist,
+                                  const std::string &boundary, const double residual)
+{
+  addMixedPrecisionSolver(app, par, solverName, gaugeName, mass, twist, boundary, residual);
+}
+
+inline void Jlqcd::addLightSolver(Application &app, const EnsembleParameters &par,
+                                  const std::string &solverName, const std::string &gaugeName,
+                                  const std::string &twist, const std::string &boundary,
+                                  const double residual)
+{
+  addLightSolver(app, par, solverName, gaugeName, par.ml, twist, boundary, residual);
+}
+
+inline void Jlqcd::addStrangeSolver(Application &app, const EnsembleParameters &par,
+                                    const std::string &solverName, const std::string &gaugeName,
+                                    const double mass, const std::string &twist,
+                                    const std::string &boundary, const double residual)
+{
+  addMixedPrecisionSolver(app, par, solverName, gaugeName, mass, twist, boundary, residual);
+}
+
+inline void Jlqcd::addStrangeSolver(Application &app, const EnsembleParameters &par,
+                                    const std::string &solverName, const std::string &gaugeName,
+                                    const std::string &twist, const std::string &boundary,
+                                    const double residual)
+{
+  addStrangeSolver(app, par, solverName, gaugeName, par.ms, twist, boundary, residual);
+}
+
+inline void Jlqcd::addHeavySolver(Application &app, const EnsembleParameters &par,
+                                  const std::string &solverName, const std::string &gaugeName,
+                                  const double mass, const std::string &twist,
+                                  const std::string &boundary, const double residual)
+{
+  addNoFailSolver(app, par, solverName, gaugeName, mass, twist, boundary, residual);
+}
+} // namespace hadpresets