diff --git a/internal/ceres/callbacks.cc b/internal/ceres/callbacks.cc
new file mode 100644
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--- /dev/null
+++ b/internal/ceres/callbacks.cc
@@ -0,0 +1,107 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2014 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+//   this list of conditions and the following disclaimer in the documentation
+//   and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+//   used to endorse or promote products derived from this software without
+//   specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: sameeragarwal@google.com (Sameer Agarwal)
+
+#include <iostream>  // NO LINT
+#include "ceres/callbacks.h"
+#include "ceres/program.h"
+#include "ceres/stringprintf.h"
+#include "glog/logging.h"
+
+namespace ceres {
+namespace internal {
+
+StateUpdatingCallback::StateUpdatingCallback(Program* program,
+                                             double* parameters)
+    : program_(program), parameters_(parameters) {}
+
+StateUpdatingCallback::~StateUpdatingCallback() {}
+
+CallbackReturnType StateUpdatingCallback::operator()(
+    const IterationSummary& summary) {
+  if (summary.step_is_successful) {
+    program_->StateVectorToParameterBlocks(parameters_);
+    program_->CopyParameterBlockStateToUserState();
+  }
+  return SOLVER_CONTINUE;
+}
+
+LoggingCallback::LoggingCallback(const MinimizerType minimizer_type,
+                                 const bool log_to_stdout)
+    : minimizer_type(minimizer_type),
+      log_to_stdout_(log_to_stdout) {}
+
+LoggingCallback::~LoggingCallback() {}
+
+CallbackReturnType LoggingCallback::operator()(
+    const IterationSummary& summary) {
+  string output;
+  if (minimizer_type == LINE_SEARCH) {
+    const char* kReportRowFormat =
+        "% 4d: f:% 8e d:% 3.2e g:% 3.2e h:% 3.2e "
+        "s:% 3.2e e:% 3d it:% 3.2e tt:% 3.2e";
+    output = StringPrintf(kReportRowFormat,
+                          summary.iteration,
+                          summary.cost,
+                          summary.cost_change,
+                          summary.gradient_max_norm,
+                          summary.step_norm,
+                          summary.step_size,
+                          summary.line_search_function_evaluations,
+                          summary.iteration_time_in_seconds,
+                          summary.cumulative_time_in_seconds);
+  } else if (minimizer_type == TRUST_REGION) {
+    const char* kReportRowFormat =
+        "% 4d: f:% 8e d:% 3.2e g:% 3.2e h:% 3.2e "
+        "rho:% 3.2e mu:% 3.2e li:% 3d it:% 3.2e tt:% 3.2e";
+    output = StringPrintf(kReportRowFormat,
+                          summary.iteration,
+                          summary.cost,
+                          summary.cost_change,
+                          summary.gradient_max_norm,
+                          summary.step_norm,
+                          summary.relative_decrease,
+                          summary.trust_region_radius,
+                          summary.linear_solver_iterations,
+                          summary.iteration_time_in_seconds,
+                          summary.cumulative_time_in_seconds);
+  } else {
+    LOG(FATAL) << "Unknown minimizer type.";
+  }
+
+  if (log_to_stdout_) {
+    cout << output << endl;
+  } else {
+    VLOG(1) << output;
+  }
+  return SOLVER_CONTINUE;
+}
+
+}  // namespace internal
+}  // namespace ceres