diff --git a/config b/config
index f7f2910..53a80d6 100644
--- a/config
+++ b/config
@@ -33,4 +33,5 @@ source "scripts/paths"
 
 # Project-specific variables below.
 [ -z "${CC}" ] && CC="gcc"
+[ -z "${CXX}" ] && CXX="g++"
 [ -z "${CFLAGS}" ] && CFLAGS="-g -O2 -W -Wall"
diff --git a/src/libiir++/.params b/src/libiir++/.params
new file mode 100644
index 0000000..7397660
--- /dev/null
+++ b/src/libiir++/.params
@@ -0,0 +1 @@
+lib c++ libiir++ iir++.h
diff --git a/src/libiir++/000_TopHeader.h b/src/libiir++/000_TopHeader.h
new file mode 100644
index 0000000..7f4e712
--- /dev/null
+++ b/src/libiir++/000_TopHeader.h
@@ -0,0 +1,32 @@
+/* libiir/src/libiir++/000_TopHeader.h
+ * 
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+#ifndef HEADER_libiirpp
+#define HEADER_libiirpp
+
+// standard includes, or includes needed for type declarations
+#include <complex>
+#include <vector>
+
+// forward declares of opaque C structures (to avoid pulling in header)
+extern "C" {
+struct iir_coeff_t;
+struct iir_filter_t;
+}
+
+/*! \defgroup libiirpp C++ library */
+
+/*! \brief All %IIR library functions and classes.
+
+\ingroup libiirpp
+
+*/
+namespace IIR {
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/000_TopSource.cc b/src/libiir++/000_TopSource.cc
new file mode 100644
index 0000000..621942d
--- /dev/null
+++ b/src/libiir++/000_TopSource.cc
@@ -0,0 +1,21 @@
+/* libiir/src/libiir++/000_TopSource.cc
+ *
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+#include "iir++.h"
+#include "iir.h"
+
+// iir.h includes <complex.h>, which #defines complex to _Complex. That's fine
+// for the C header above, but will mess with our code definitions below.
+#undef complex
+
+// Below are all the includes used throughout the library.
+
+namespace IIR {
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4
+*/
diff --git a/src/libiir++/100_Coeff.cc b/src/libiir++/100_Coeff.cc
new file mode 100644
index 0000000..1b58089
--- /dev/null
+++ b/src/libiir++/100_Coeff.cc
@@ -0,0 +1,80 @@
+/* libiir/src/libiir++/100_Coeff.cc
+ * 
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+
+
+Coeff::Coeff(int nc, const double* c, int nd, const double* d)
+{
+    cc_ = iir_coeff_new(nc, c, nd, d);
+}
+
+
+
+Coeff::Coeff(const struct iir_coeff_t* cc)
+{
+    cc_ = iir_coeff_copy(cc);
+}
+
+
+
+Coeff::Coeff(const Coeff& other)
+{
+    cc_ = iir_coeff_copy(other.cc_);
+}
+
+
+
+Coeff::~Coeff()
+{
+    iir_coeff_free(cc_);
+}
+
+
+
+int
+Coeff::nc() const
+{
+    return iir_coeff_get_nc(cc_);
+}
+
+
+
+double
+Coeff::c(int idx) const
+{
+    return iir_coeff_get_c(cc_, idx);
+}
+
+
+
+int
+Coeff::nd() const
+{
+    return iir_coeff_get_nd(cc_);
+}
+
+
+
+double
+Coeff::d(int idx) const
+{
+    return iir_coeff_get_d(cc_, idx);
+}
+
+
+
+std::complex<double>
+Coeff::response(double freq) const
+{
+    return std::complex<double>(iir_response_c(cc_, freq));
+}
+
+
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/100_Coeff.h b/src/libiir++/100_Coeff.h
new file mode 100644
index 0000000..64f37d5
--- /dev/null
+++ b/src/libiir++/100_Coeff.h
@@ -0,0 +1,122 @@
+/* libiir/src/libiir++/100_Coeff.h
+ * 
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+
+
+/*! \defgroup libiirpp_coeff Coefficient handling
+
+\ingroup libiirpp
+
+A set of coefficients for a single stage %IIR filter is represented by an
+instance of the \ref Coeff class. This class is often instantiated through
+one of the common filter generator functions (see \ref libiirpp_common_filters).
+
+*/
+
+
+
+/*! \brief %IIR filter coefficient set
+
+\ingroup libiirpp_coeff
+
+An instance of this class represents the set of coefficients used to implement
+a single-phase %IIR filter. See \ref iir_structure for more information.
+
+*/
+class Coeff {
+public:
+    /*! \brief Constructor with raw coefficients.
+
+    \param nc Number of \a c coefficients, ≥ 1.
+    \param c Array of \a c coefficients.
+    \param nd Number of \a d coefficients, ≥ 1.
+    \param d Array of \a d coefficients.
+
+    */
+    Coeff(int nc, const double* c, int nd, const double* d);
+
+    /*! \brief Constructor from C library object.
+
+    \param cc Pointer to existing coefficient object.
+
+    */
+    Coeff(const struct iir_coeff_t* cc);
+
+    /*! \brief Copy constructor.
+
+    \param other Object to copy.
+
+    Performs a full deep copy of the set of coefficients from \a other.
+
+    */
+    Coeff(const Coeff& other);
+
+    /*! \brief Destructor. */
+    virtual ~Coeff();
+
+
+
+    /*! \brief Count number of \a c coefficients.
+
+    \returns Number of \a c coefficients, ≥ 1.
+
+    */
+    int nc() const;
+
+    /*! \brief Retrieve \a c coefficient by index.
+
+    \param idx Index of coefficient (0 ≤ \a idx < \ref nc()).
+    \returns Value of \a c coefficient at index \a idx.
+
+    */
+    double c(int idx) const;
+
+    /*! \brief Count number of \a d coefficients.
+
+    \returns Number of \a d coefficients, ≥ 1.
+
+    */
+    int nd() const;
+
+    /*! \brief Retrieve \a d coefficient by index.
+
+    \param idx Index of coefficient (0 ≤ \a idx < \ref nd()).
+    \returns Value of \a d coefficient at index \a idx.
+
+    */
+    double d(int idx) const;
+
+
+
+    /*! \brief Evaluate response of filter at given frequency.
+
+    \param freq Frequency (0 ≤ \a freq ≤ 1).
+    \returns Complex response of filter at given frequency.
+
+    Returns the steady-state response of the filter to a pure input signal of
+    the given frequency. \a freq is expressed as a fraction of the intended
+    sampling rate (with 0.5 being the Nyquist frequency).
+
+    */
+    std::complex<double> response(double freq) const;
+
+private:
+    // allow the Filter class to access cc_ directly
+    friend class Filter;
+
+    // our internal representation is the C object
+    struct iir_coeff_t* cc_;
+
+    // disallow assignment; object is immutable
+    Coeff& operator=(const Coeff& other);
+};
+
+
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/200_Filter.cc b/src/libiir++/200_Filter.cc
new file mode 100644
index 0000000..027b0de
--- /dev/null
+++ b/src/libiir++/200_Filter.cc
@@ -0,0 +1,104 @@
+/* libiir/src/libiir++/200_Filter.cc
+ * 
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+
+
+Filter::Filter(const Coeff& coeff)
+{
+    coeff_.push_back(new Coeff(coeff));
+    fi_ = iir_filter_new(coeff.cc_);
+}
+
+
+
+Filter::Filter(const Filter& other)
+{
+    for(int pos = 0, max = other.coeff_.size(); pos < max; ++pos) {
+        Coeff* cc = new Coeff(*other.coeff_[pos]);
+        coeff_.push_back(cc);
+
+        if(!pos) fi_ = iir_filter_new(cc->cc_);
+        else iir_filter_chain(fi_, cc->cc_);
+    }
+}
+
+
+
+Filter::Filter(const char* desc)
+{
+    fi_ = iir_parse(desc);
+    if(!fi_) return;
+
+    for(int pos = 0, max = iir_filter_coeff_sets(fi_); pos < max; ++pos) {
+        struct iir_coeff_t* c = iir_filter_coeff_set(fi_, pos);
+        coeff_.push_back(new Coeff(c));
+        iir_coeff_free(c);
+    }
+}
+
+
+
+Filter::~Filter()
+{
+    for(int pos = 0, max = coeff_.size(); pos < max; ++pos) delete coeff_[pos];
+    iir_filter_free(fi_);
+}
+
+
+
+bool
+Filter::valid() const
+{
+    return fi_;
+}
+
+
+
+double
+Filter::f(double x)
+{
+    return iir_filter(fi_, x);
+}
+
+
+
+int
+Filter::numCoeffSet() const
+{
+    return coeff_.size();
+}
+
+
+
+const Coeff&
+Filter::getCoeffSet(int idx) const
+{
+    return *(coeff_[idx]);
+}
+
+
+
+void
+Filter::chainCoeffSet(const Coeff& coeff)
+{
+    coeff_.push_back(new Coeff(coeff));
+    iir_filter_chain(fi_, coeff.cc_);
+}
+
+
+
+std::complex<double>
+Filter::response(double freq) const
+{
+    return iir_response(fi_, freq);
+}
+
+
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/200_Filter.h b/src/libiir++/200_Filter.h
new file mode 100644
index 0000000..c073c4f
--- /dev/null
+++ b/src/libiir++/200_Filter.h
@@ -0,0 +1,152 @@
+/* libiir/src/libiir++/200_Filter.h
+ * 
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+
+
+/*! \defgroup libiirpp_filter Basic IIR filtering
+
+\ingroup libiirpp
+
+An instance of the \ref Filter class represents the structure and state of an
+%IIR filter. It may be built up with \ref Coeff instances or parsed from a
+user-supplied string (see \ref string_desc).
+
+*/
+
+
+
+/*! \brief %IIR filter coefficient set
+
+\ingroup libiirpp_filter
+
+An instance of this class contains both a copy of the set of coefficients used
+in each filter stage (of which there may be multiple), and all of the state
+(i.e.  previous inputs and outputs) associated with each stage.
+
+*/
+class Filter {
+public:
+    /*! \brief Construct from coefficient set.
+
+    \param coeff Coefficient set.
+
+    This constructor builds a filter chain with one stage. Additional stages may
+    be added via \ref chainCoeffSet(). This constructor will always result in a
+    valid object.
+
+    */
+    Filter(const Coeff& coeff);
+
+    /*! \brief Copy constructor.
+
+    \param other Filter to copy.
+
+    Copies the structure (but not the state) of the filter \a other. This
+    constructor will always result in a valid object.
+
+    */
+    Filter(const Filter& other);
+
+    /*! \brief Construct from filter description string.
+
+    \param desc Description string.
+
+    This constructor will parse the description string \a desc (see
+    \ref string_desc for details on what is accepted) and build up a filter
+    as described.
+
+    If the parsing step fails, then \ref valid() will return false and the
+    object must not be used (no other functions except the destructor will be
+    safe to call).
+
+    */
+    Filter(const char* desc);
+
+    /*! \brief Destructor. */
+    virtual ~Filter();
+
+
+
+    /*! \brief Determine whether object is valid.
+
+    \retval true if object is valid.
+    \retval false if object is not valid.
+
+    A Filter object might not be valid if it was constructed from a description
+    string that contained an error. In that case this function will return
+    \a false and the object should not be used (no other functions except the
+    destructor will be safe to call).
+
+    */
+    bool valid() const;
+
+
+
+    /*! \brief %Filter a sample.
+
+    \param x Sample.
+    \returns %Filter output.
+
+    Injects a single sample into the filter and returns the output value.
+
+    */
+    double f(double x);
+
+
+
+    /*! \brief Retrieve number of coefficient sets.
+
+    \returns Number of sets in use (≥1).
+
+    */
+    int numCoeffSet() const;
+
+    /*! \brief Retrieve coefficient set.
+
+    \param idx Index of set (0 ≤ \a idx < \ref numCoeffSet()).
+    \returns Reference to coefficient set.
+
+    */
+    const Coeff& getCoeffSet(int idx) const;
+
+    /*! \brief Add another set of coefficients to the filter chain.
+
+    \param coeff Coefficient set to add.
+
+    */
+    void chainCoeffSet(const Coeff& coeff);
+
+
+
+    /*! \brief Evaluate response of filter at given frequency.
+
+    \param freq Frequency (0 ≤ \a freq ≤ 1).
+    \returns Complex response of filter at given frequency.
+
+    Returns the steady-state response of the filter to a pure input signal of
+    the given frequency. \a freq is expressed as a fraction of the intended
+    sampling rate (with 0.5 being the Nyquist frequency).
+
+    */
+    std::complex<double> response(double freq) const;
+
+private:
+    // one entry per set of coefficients, in order of execution
+    std::vector<const Coeff*> coeff_;
+
+    // the C object has both state and its own copy of the coefficients
+    struct iir_filter_t* fi_;
+
+    // disallow assignment
+    Filter& operator=(const Filter& other);
+};
+
+
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/300_common_filters.cc b/src/libiir++/300_common_filters.cc
new file mode 100644
index 0000000..a2788ac
--- /dev/null
+++ b/src/libiir++/300_common_filters.cc
@@ -0,0 +1,58 @@
+/* libiir/src/libiir++/300_common_filters.cc
+ * 
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+
+
+Coeff
+ButterworthLowPass(int order, double gain, double corner)
+{
+    struct iir_coeff_t* cc = iir_butterworth_lowpass(order, gain, corner);
+    Coeff ret(cc);
+    iir_coeff_free(cc);
+    return ret;
+}
+
+
+
+Coeff
+ButterworthHighPass(int order, double gain, double corner)
+{
+    struct iir_coeff_t* cc = iir_butterworth_highpass(order, gain, corner);
+    Coeff ret(cc);
+    iir_coeff_free(cc);
+    return ret;
+}
+
+
+
+Coeff
+ButterworthBandPass(int order, double gain, double corner1, double corner2)
+{
+    struct iir_coeff_t* cc = iir_butterworth_bandpass(order, gain, corner1,
+        corner2);
+    Coeff ret(cc);
+    iir_coeff_free(cc);
+    return ret;
+}
+
+
+
+Coeff
+ButterworthBandStop(int order, double gain, double corner1, double corner2)
+{
+    struct iir_coeff_t* cc = iir_butterworth_bandstop(order, gain, corner1,
+        corner2);
+    Coeff ret(cc);
+    iir_coeff_free(cc);
+    return ret;
+}
+
+
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/300_common_filters.h b/src/libiir++/300_common_filters.h
new file mode 100644
index 0000000..ddc7c20
--- /dev/null
+++ b/src/libiir++/300_common_filters.h
@@ -0,0 +1,144 @@
+/* libiir/src/libiir++/300_common_filters.h
+ * 
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+
+
+/*! \defgroup libiirpp_common_filters Common types of IIR filter
+
+\ingroup libiirpp
+
+Routines in this section can be used to build a coefficient set that matches a
+common %IIR filter type. These can be passed to the \ref Filter class to build
+up an actual instance of a filter.
+
+\note It is common to build higher-order filters by chaining together several
+    lower-order filters. The functions in this section do not do that directly,
+    but are intended to build the individual components of a chain. See
+    \ref Filter::Filter(const char*) for an interface which performs this
+    automatically.
+
+*/
+/*!@{*/
+
+
+
+/*! \brief nth-order Butterworth low-pass
+
+\param order Order of filter (≥1).
+\param gain Linear gain of filter.
+\param corner Corner frequency expressed as a fraction of Nyquist
+    (0 ≤ \a corner ≤ 1).
+
+\returns %IIR filter coefficient set.
+
+Uses the Exstrom labs code to compute the coefficients of an nth-order (param
+\a order) Butterworth-type low pass filter with gain \a gain and corner
+frequency \a corner.
+
+Note it is recommended to chain multiple filters together to build anything
+greater than a 4th-order filter. This function won't do that directly for you.
+\a gain will usually be set to be 1.0.
+
+The corner frequency corner is expressed as a fraction of the sampling
+frequency (which is of course not known by the %IIR code). It should lie between
+0 (0Hz) and 1 (the Nyquist frequency, or ½ the sampling frequency). 
+
+*/
+Coeff ButterworthLowPass(int order, double gain, double corner);
+
+
+
+/*! \brief nth-order Butterworth high-pass
+
+\param order Order of filter (≥1).
+\param gain Linear gain of filter.
+\param corner Corner frequency expressed as a fraction of Nyquist
+    (0 ≤ \a corner ≤ 1).
+
+\returns %IIR filter coefficient set.
+
+Uses the Exstrom labs code to compute the coefficients of an nth-order (param
+\a order) Butterworth-type high pass filter with gain \a gain and corner
+frequency \a corner.
+
+Note it is recommended to chain multiple filters together to build anything
+greater than a 4th-order filter. This function won't do that directly for you.
+\a gain will usually be set to be 1.0.
+
+The corner frequency corner is expressed as a fraction of the sampling
+frequency (which is of course not known by the %IIR code). It should lie between
+0 (0Hz) and 1 (the Nyquist frequency, or ½ the sampling frequency). 
+
+*/
+Coeff ButterworthHighPass(int order, double gain, double corner);
+
+
+
+/*! \brief nth-order Butterworth band-pass
+
+\param order Order of filter (≥1).
+\param gain Linear gain of filter.
+\param corner1 Low corner frequency expressed as a fraction of Nyquist
+    (0 ≤ \a corner ≤ 1).
+\param corner2 High corner frequency expressed as a fraction of Nyquist
+    (0 ≤ \a corner ≤ 1).
+
+\returns %IIR filter coefficient set.
+
+Uses the Exstrom labs code to compute the coefficients of an nth-order (param
+\a order) Butterworth-type band pass filter with gain \a gain and corner
+frequencies \a corner1 and \a corner2.
+
+Note it is recommended to chain multiple filters together to build anything
+greater than a 4th-order filter. This function won't do that directly for you.
+\a gain will usually be set to be 1.0.
+
+The corner frequencies \a corner1 and \a corner2 are expressed as a fraction of
+the sampling frequency (which is of course not known by the %IIR code). They
+should lie between 0 (0Hz) and 1 (the Nyquist frequency, or ½ the sampling
+frequency), and \a corner2 should be greater than \a corner1.
+
+*/
+Coeff ButterworthBandPass(int order, double gain, double corner1,
+    double corner2);
+
+
+
+/*! \brief nth-order Butterworth band-stop
+
+\param order Order of filter (≥1).
+\param gain Linear gain of filter.
+\param corner1 Low corner frequency expressed as a fraction of Nyquist
+    (0 ≤ \a corner ≤ 1).
+\param corner2 High corner frequency expressed as a fraction of Nyquist
+    (0 ≤ \a corner ≤ 1).
+
+\returns %IIR filter coefficient set.
+
+Uses the Exstrom labs code to compute the coefficients of an nth-order (param
+\a order) Butterworth-type band stop filter with gain \a gain and corner
+frequencies \a corner1 and \a corner2.
+
+Note it is recommended to chain multiple filters together to build anything
+greater than a 4th-order filter. This function won't do that directly for you.
+\a gain will usually be set to be 1.0.
+
+The corner frequencies \a corner1 and \a corner2 are expressed as a fraction of
+the sampling frequency (which is of course not known by the %IIR code). They
+should lie between 0 (0Hz) and 1 (the Nyquist frequency, or ½ the sampling
+frequency), and \a corner2 should be greater than \a corner1.
+
+*/
+Coeff ButterworthBandStop(int order, double gain, double corner1,
+    double corner2);
+
+
+
+/*!@}*/
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/999_BottomHeader.h b/src/libiir++/999_BottomHeader.h
new file mode 100644
index 0000000..883d3b7
--- /dev/null
+++ b/src/libiir++/999_BottomHeader.h
@@ -0,0 +1,14 @@
+/* libiir/src/libiir++/999_BottomHeader.h
+ *
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+} // end namespace IIR
+
+#endif
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4:syntax=cpp.doxygen
+*/
diff --git a/src/libiir++/999_BottomSource.cc b/src/libiir++/999_BottomSource.cc
new file mode 100644
index 0000000..435f4d6
--- /dev/null
+++ b/src/libiir++/999_BottomSource.cc
@@ -0,0 +1,12 @@
+/* libiir/src/libiir++/999_BottomSource.cpp
+ *
+ *  Copyright: ©2014, Laurence Withers.
+ *  Author: Laurence Withers <l@lwithers.me.uk>
+ *  License: GPLv3
+ */
+
+} // end namspace IIR
+
+/* options for text editors
+vim: expandtab:ts=4:sw=4
+*/
diff --git a/src/libiir++/build.default b/src/libiir++/build.default
new file mode 100644
index 0000000..902b4ed
--- /dev/null
+++ b/src/libiir++/build.default
@@ -0,0 +1 @@
+source src/libiir++/build.lib
diff --git a/src/libiir++/build.install b/src/libiir++/build.install
new file mode 100644
index 0000000..e796001
--- /dev/null
+++ b/src/libiir++/build.install
@@ -0,0 +1 @@
+source src/libiir++/build.install-lib
diff --git a/src/libiir++/build.install-lib b/src/libiir++/build.install-lib
new file mode 100644
index 0000000..54af69b
--- /dev/null
+++ b/src/libiir++/build.install-lib
@@ -0,0 +1,35 @@
+build_target libiir++
+
+# make paths (this is for Gentoo in particular)
+build_dir_tree "${LIBDIR}" || return 1
+build_dir_tree "${BINDIR}" || return 1
+build_dir_tree "${INCLUDEDIR}" || return 1
+
+# install library
+echo "Installing libraries into '${LIBDIR}'"
+install_file ${libiirpp} ${LIBDIR} 0755 || return 1
+BASE="${libiirpp_BASE}.so"
+MAJOR="${BASE}.${SOMAJOR}"
+MICRO="${MAJOR}.${SOMICRO}"
+install_symlink "${BASE}" "${MICRO}" "${LIBDIR}"
+
+# install header
+echo "Installing header file '${libiirpp_HEADER}' into ${INCLUDEDIR}"
+install_header ${libiirpp_HEADER} ${INCLUDEDIR} 0644 || return 1
+
+# install config script
+echo "Installing config script into ${PKGCONFDIR}"
+CONFFILE="${INSTALL_PREFIX}${BINDIR}/libiir++-config"
+
+do_cmd rm -f "${CONFFILE}"
+do_cmd_redir "${CONFFILE}" sed \
+    -e "s,@VERSION@,${VERSION}," \
+    -e "s,@LIB_DIR@,${LIBDIR}," \
+    -e "s,@INCLUDE_DIR@,${INCLUDEDIR}," \
+    -e "s,@DEP_CFLAGS@,${libiirpp_DEP_CFLAGS}," \
+    -e "s,@DEP_LIBS@,${libiirpp_DEP_LIBS}," \
+    src/libiir++/config-script
+do_cmd chmod 0644 "${CONFFILE}"
+print_success "Done"
+
+# vim: syntax=sh:expandtab:ts=4:sw=4
diff --git a/src/libiir++/build.lib b/src/libiir++/build.lib
new file mode 100644
index 0000000..7ece41f
--- /dev/null
+++ b/src/libiir++/build.lib
@@ -0,0 +1,58 @@
+# These are external variables, and shouldn't clash with anything else
+#  libiirpp
+#  libiirpp_BUILT
+#  libiirpp_HEADER
+#  libiirpp_BASE
+#  libiirpp_DEP_CFLAGS
+#  libiirpp_DEP_LIBS
+
+build_target libiir
+
+if [ -z ${libiirpp_BUILT} ]
+then
+    libiirpp_BASE=libiir++
+    source src/libiir++/soversion
+
+    libiirpp="obj/${libiirpp_BASE}.so.${SOMAJOR}.${SOMICRO}"
+    libiirpp_DEP_CFLAGS=""
+    libiirpp_DEP_LIBS="${libiir}"
+    SO_EXTRA="${libiirpp_DEP_CFLAGS} ${libiirpp_DEP_LIBS} -lstdc++ -lc \
+        -D_GNU_SOURCE"
+
+    echo "Building library ${libiirpp}..."
+
+    do_cmd source src/libiir++/build.monolithic || return 1
+
+    MODIFIED=0
+    for test in ${MONOLITHIC_TESTS} ${HDR} ${SRC}
+    do
+        if [ ${test} -nt ${libiirpp} ]
+        then
+            MODIFIED=1
+            break
+        fi
+    done
+
+    if [ ${MODIFIED} -ne 0 ]
+    then
+        echo " Compiling"
+
+        SONAME="${libiirpp_BASE}.so.${SOMAJOR}"
+        do_cmd ${CXX} ${CFLAGS} -Iobj -shared -fpic -o "${libiirpp}" \
+            -Wl,-soname,${SONAME} \
+            ${SRC} ${SO_EXTRA} || return 1
+
+        # make tests work
+        do_cmd ln -sf $(basename ${libiirpp}) obj/${SONAME} || return 1
+
+        print_success "Library built"
+    else
+        print_success "Library up to date"
+    fi
+
+    libiirpp_BUILT=1
+    libiirpp_HEADER=${HDR}
+
+fi
+
+# vim: syntax=sh:expandtab:ts=4:sw=4
diff --git a/src/libiir++/build.monolithic b/src/libiir++/build.monolithic
new file mode 100644
index 0000000..f28385e
--- /dev/null
+++ b/src/libiir++/build.monolithic
@@ -0,0 +1,21 @@
+# These are external variables, and shouldn't clash with anything else
+#  libiirpp_MONOLITHIC
+
+SRC="obj/libiir++.cpp"
+HDR="obj/iir++.h"
+
+MONOLITHIC_TESTS="src/libiir++/build.lib src/libiir++/build.monolithic"
+
+if [ -z "${libiirpp_MONOLITHIC}" ]
+then
+    MONOLITHIC_SOURCE="$(find src/libiir++/ -name '*.h' | sort)"
+    make_monolithic ${HDR} Ch || return 1
+
+    MONOLITHIC_SOURCE="$(find src/libiir++/ -name '*.cc' | sort)"
+    make_monolithic ${SRC} C || return 1
+
+    libiirpp_MONOLITHIC=1
+    MONOLITHIC_DOC="${MONOLITHIC_DOC} ${HDR}"
+fi
+
+# vim: syntax=sh:expandtab:ts=4:sw=4
diff --git a/src/libiir++/config-script b/src/libiir++/config-script
new file mode 100644
index 0000000..be6f4e4
--- /dev/null
+++ b/src/libiir++/config-script
@@ -0,0 +1,97 @@
+#!/bin/bash
+# libiir/src/libiir++/config-script
+#
+# libiir++-config template. Variables are finalised at install time.
+#
+dep_cflags="@DEP_CFLAGS@"
+dep_libs="@DEP_LIBS@"
+include_dir="@INCLUDE_DIR@"
+include_dir_set="no"
+lib_dir="@LIB_DIR@"
+lib_dir_set="no"
+
+
+
+usage() {
+    cat <<EOF
+Usage: libiir++-config [options]
+Options:
+        [--version]
+        [--libs]
+        [--libdir[=DIR]]
+        [--cflags]
+        [--includedir[=DIR]]
+EOF
+    exit $1
+}
+
+
+
+[ $# -eq 0 ] && usage 1 1>&2
+
+
+
+while [ $# -gt 0 ]
+do
+    case "$1" in
+        -*=*) 
+            optarg="$(echo "$1" | sed 's/[-_a-zA-Z0-9]*=//')"
+        ;;
+
+        *)
+            optarg=""
+        ;;
+    esac
+
+    case "$1" in
+        --libdir=*)
+            lib_dir="${optarg}"
+            lib_dir_set="yes"
+        ;;
+
+        --libdir)
+            echo_lib_dir="yes"
+        ;;
+
+        --includedir=*)
+            include_dir="${optarg}"
+            include_dir_set="yes"
+        ;;
+
+        --includedir)
+            echo_include_dir="yes"
+        ;;
+
+        --version)
+            echo "@VERSION@"
+            exit 0
+        ;;
+
+        --cflags)
+            [ "${include_dir}" != "/usr/include" ] && includes="-I${include_dir}"
+            echo_cflags="yes"
+        ;;
+
+        --libs)
+            echo_libs="yes"
+        ;;
+
+        *)
+            usage 1 1>&2
+        ;;
+    esac
+
+    shift
+done
+
+
+
+[ "${echo_prefix}" == "yes" ] && echo "${prefix}"
+[ "${echo_exec_prefix}" == "yes" ] && echo "${exec_prefix}"
+[ "${echo_cflags}" == "yes" ] && echo "${dep_cflags} ${includes}"
+[ "${echo_libs}" == "yes" ] && echo "${dep_libs} -L${lib_dir} -liir++"
+true
+
+
+
+# kate: 
diff --git a/src/libiir++/soversion b/src/libiir++/soversion
new file mode 100644
index 0000000..216f81c
--- /dev/null
+++ b/src/libiir++/soversion
@@ -0,0 +1,15 @@
+# libiir/src/libiir++/soversion
+#
+#  Copyright: ©2014, Laurence Withers.
+#  Author: Laurence Withers <l@lwithers.me.uk>
+#  License: GPLv3
+#
+
+
+
+# SOMAJOR is included in the library's soname, and needs to be bumped
+# after a binary-incompatible release. It is a single integer.
+SOMAJOR=0
+
+# SOMICRO is bumped every time there is a binary-compatible release.
+SOMICRO=0