diff --git a/CHANGES.md b/CHANGES.md
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,7 @@
+## Version 0.4.5.1
+
+ * Restore GHC 7.4 support (#124)
+
 ## Version 0.4.5.0
 
  * Support for GHC 8.0 added; support for GHC 7.4 dropped
diff --git a/Data/Csv/Conversion.hs b/Data/Csv/Conversion.hs
--- a/Data/Csv/Conversion.hs
+++ b/Data/Csv/Conversion.hs
@@ -2,8 +2,6 @@
     BangPatterns,
     CPP,
     DefaultSignatures,
-    DataKinds,
-    PolyKinds,
     FlexibleContexts,
     FlexibleInstances,
     KindSignatures,
@@ -14,6 +12,11 @@
     TypeOperators,
     UndecidableInstances
     #-}
+
+#if __GLASGOW_HASKELL__ >= 800
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE PolyKinds #-}
+#endif
 
 module Data.Csv.Conversion
     (
diff --git a/benchmarks/presidents.csv b/benchmarks/presidents.csv
new file mode 100644
--- /dev/null
+++ b/benchmarks/presidents.csv
@@ -0,0 +1,44 @@
+1,George Washington,http://en.wikipedia.org/wiki/George_Washington,30/04/1789,04/03/1797,Independent,Virginia
+2,John Adams,http://en.wikipedia.org/wiki/John_Adams,04/03/1797,04/03/1801,Federalist,Massachusetts
+3,Thomas Jefferson,http://en.wikipedia.org/wiki/Thomas_Jefferson,04/03/1801,04/03/1809,Democratic-Republican,Virginia
+4,James Madison,http://en.wikipedia.org/wiki/James_Madison,04/03/1809,04/03/1817,Democratic-Republican,Virginia
+5,James Monroe,http://en.wikipedia.org/wiki/James_Monroe,04/03/1817,04/03/1825,Democratic-Republican,Virginia
+6,John Quincy Adams,http://en.wikipedia.org/wiki/John_Quincy_Adams,04/03/1825,04/03/1829,Democratic-Republican/National Republican,Massachusetts
+7,Andrew Jackson,http://en.wikipedia.org/wiki/Andrew_Jackson,04/03/1829,04/03/1837,Democratic,Tennessee
+8,Martin Van Buren,http://en.wikipedia.org/wiki/Martin_Van_Buren,04/03/1837,04/03/1841,Democratic,New York
+9,William Henry Harrison,http://en.wikipedia.org/wiki/William_Henry_Harrison,04/03/1841,04/04/1841,Whig,Ohio
+10,John Tyler,http://en.wikipedia.org/wiki/John_Tyler,04/04/1841,04/03/1845,Whig,Virginia
+11,James K. Polk,http://en.wikipedia.org/wiki/James_K._Polk,04/03/1845,04/03/1849,Democratic,Tennessee
+12,Zachary Taylor,http://en.wikipedia.org/wiki/Zachary_Taylor,04/03/1849,09/07/1850,Whig,Louisiana
+13,Millard Fillmore,http://en.wikipedia.org/wiki/Millard_Fillmore,09/07/1850,04/03/1853,Whig,New York
+14,Franklin Pierce,http://en.wikipedia.org/wiki/Franklin_Pierce,04/03/1853,04/03/1857,Democratic,New Hampshire
+15,James Buchanan,http://en.wikipedia.org/wiki/James_Buchanan,04/03/1857,04/03/1861,Democratic,Pennsylvania
+16,Abraham Lincoln,http://en.wikipedia.org/wiki/Abraham_Lincoln,04/03/1861,15/04/1865,Republican/National Union,Illinois
+17,Andrew Johnson,http://en.wikipedia.org/wiki/Andrew_Johnson,15/04/1865,04/03/1869,Democratic/National Union,Tennessee
+18,Ulysses S. Grant,http://en.wikipedia.org/wiki/Ulysses_S._Grant,04/03/1869,04/03/1877,Republican,Ohio
+19,Rutherford B. Hayes,http://en.wikipedia.org/wiki/Rutherford_B._Hayes,04/03/1877,04/03/1881,Republican,Ohio
+20,James A. Garfield,http://en.wikipedia.org/wiki/James_A._Garfield,04/03/1881,19/09/1881,Republican,Ohio
+21,Chester A. Arthur,http://en.wikipedia.org/wiki/Chester_A._Arthur,19/09/1881,04/03/1885,Republican,New York
+22,Grover Cleveland,http://en.wikipedia.org/wiki/Grover_Cleveland,04/03/1885,04/03/1889,Democratic,New York
+23,Benjamin Harrison,http://en.wikipedia.org/wiki/Benjamin_Harrison,04/03/1889,04/03/1893,Republican,Indiana
+24,Grover Cleveland (2nd term),http://en.wikipedia.org/wiki/Grover_Cleveland,04/03/1893,04/03/1897,Democratic,New York
+25,William McKinley,http://en.wikipedia.org/wiki/William_McKinley,04/03/1897,14/09/1901,Republican,Ohio
+26,Theodore Roosevelt,http://en.wikipedia.org/wiki/Theodore_Roosevelt,14/09/1901,04/03/1909,Republican,New York
+27,William Howard Taft,http://en.wikipedia.org/wiki/William_Howard_Taft,04/03/1909,04/03/1913,Republican,Ohio
+28,Woodrow Wilson,http://en.wikipedia.org/wiki/Woodrow_Wilson,04/03/1913,04/03/1921,Democratic,New Jersey
+29,Warren G. Harding,http://en.wikipedia.org/wiki/Warren_G._Harding,04/03/1921,02/08/1923,Republican,Ohio
+30,Calvin Coolidge,http://en.wikipedia.org/wiki/Calvin_Coolidge,02/08/1923,04/03/1929,Republican,Massachusetts
+31,Herbert Hoover,http://en.wikipedia.org/wiki/Herbert_Hoover,04/03/1929,04/03/1933,Republican,Iowa
+32,Franklin D. Roosevelt,http://en.wikipedia.org/wiki/Franklin_D._Roosevelt,04/03/1933,12/04/1945,Democratic,New York
+33,Harry S. Truman,http://en.wikipedia.org/wiki/Harry_S._Truman,12/04/1945,20/01/1953,Democratic,Missouri
+34,Dwight D. Eisenhower,http://en.wikipedia.org/wiki/Dwight_D._Eisenhower,20/01/1953,20/01/1961,Republican,Texas
+35,John F. Kennedy,http://en.wikipedia.org/wiki/John_F._Kennedy,20/01/1961,22/11/1963,Democratic,Massachusetts
+36,Lyndon B. Johnson,http://en.wikipedia.org/wiki/Lyndon_B._Johnson,22/11/1963,20/01/1969,Democratic,Texas
+37,Richard Nixon,http://en.wikipedia.org/wiki/Richard_Nixon,20/01/1969,09/08/1974,Republican,California
+38,Gerald Ford,http://en.wikipedia.org/wiki/Gerald_Ford,09/08/1974,20/01/1977,Republican,Michigan
+39,Jimmy Carter,http://en.wikipedia.org/wiki/Jimmy_Carter,20/01/1977,20/01/1981,Democratic,Georgia
+40,Ronald Reagan,http://en.wikipedia.org/wiki/Ronald_Reagan,20/01/1981,20/01/1989,Republican,California
+41,George H. W. Bush,http://en.wikipedia.org/wiki/George_H._W._Bush,20/01/1989,20/01/1993,Republican,Texas
+42,Bill Clinton,http://en.wikipedia.org/wiki/Bill_Clinton,20/01/1993,20/01/2001,Democratic,Arkansas
+43,George W. Bush,http://en.wikipedia.org/wiki/George_W._Bush,20/01/2001,20/01/2009,Republican,Texas
+44,Barack Obama,http://en.wikipedia.org/wiki/Barack_Obama,20/01/2009,Incumbent,  Democratic  ,Illinois
diff --git a/benchmarks/presidents_with_header.csv b/benchmarks/presidents_with_header.csv
new file mode 100644
--- /dev/null
+++ b/benchmarks/presidents_with_header.csv
@@ -0,0 +1,45 @@
+Presidency,President,Wikipedia Entry,Took office,Left office,Party,Home State
+1,George Washington,http://en.wikipedia.org/wiki/George_Washington,30/04/1789,04/03/1797,Independent,Virginia
+2,John Adams,http://en.wikipedia.org/wiki/John_Adams,04/03/1797,04/03/1801,Federalist,Massachusetts
+3,Thomas Jefferson,http://en.wikipedia.org/wiki/Thomas_Jefferson,04/03/1801,04/03/1809,Democratic-Republican,Virginia
+4,James Madison,http://en.wikipedia.org/wiki/James_Madison,04/03/1809,04/03/1817,Democratic-Republican,Virginia
+5,James Monroe,http://en.wikipedia.org/wiki/James_Monroe,04/03/1817,04/03/1825,Democratic-Republican,Virginia
+6,John Quincy Adams,http://en.wikipedia.org/wiki/John_Quincy_Adams,04/03/1825,04/03/1829,Democratic-Republican/National Republican,Massachusetts
+7,Andrew Jackson,http://en.wikipedia.org/wiki/Andrew_Jackson,04/03/1829,04/03/1837,Democratic,Tennessee
+8,Martin Van Buren,http://en.wikipedia.org/wiki/Martin_Van_Buren,04/03/1837,04/03/1841,Democratic,New York
+9,William Henry Harrison,http://en.wikipedia.org/wiki/William_Henry_Harrison,04/03/1841,04/04/1841,Whig,Ohio
+10,John Tyler,http://en.wikipedia.org/wiki/John_Tyler,04/04/1841,04/03/1845,Whig,Virginia
+11,James K. Polk,http://en.wikipedia.org/wiki/James_K._Polk,04/03/1845,04/03/1849,Democratic,Tennessee
+12,Zachary Taylor,http://en.wikipedia.org/wiki/Zachary_Taylor,04/03/1849,09/07/1850,Whig,Louisiana
+13,Millard Fillmore,http://en.wikipedia.org/wiki/Millard_Fillmore,09/07/1850,04/03/1853,Whig,New York
+14,Franklin Pierce,http://en.wikipedia.org/wiki/Franklin_Pierce,04/03/1853,04/03/1857,Democratic,New Hampshire
+15,James Buchanan,http://en.wikipedia.org/wiki/James_Buchanan,04/03/1857,04/03/1861,Democratic,Pennsylvania
+16,Abraham Lincoln,http://en.wikipedia.org/wiki/Abraham_Lincoln,04/03/1861,15/04/1865,Republican/National Union,Illinois
+17,Andrew Johnson,http://en.wikipedia.org/wiki/Andrew_Johnson,15/04/1865,04/03/1869,Democratic/National Union,Tennessee
+18,Ulysses S. Grant,http://en.wikipedia.org/wiki/Ulysses_S._Grant,04/03/1869,04/03/1877,Republican,Ohio
+19,Rutherford B. Hayes,http://en.wikipedia.org/wiki/Rutherford_B._Hayes,04/03/1877,04/03/1881,Republican,Ohio
+20,James A. Garfield,http://en.wikipedia.org/wiki/James_A._Garfield,04/03/1881,19/09/1881,Republican,Ohio
+21,Chester A. Arthur,http://en.wikipedia.org/wiki/Chester_A._Arthur,19/09/1881,04/03/1885,Republican,New York
+22,Grover Cleveland,http://en.wikipedia.org/wiki/Grover_Cleveland,04/03/1885,04/03/1889,Democratic,New York
+23,Benjamin Harrison,http://en.wikipedia.org/wiki/Benjamin_Harrison,04/03/1889,04/03/1893,Republican,Indiana
+24,Grover Cleveland (2nd term),http://en.wikipedia.org/wiki/Grover_Cleveland,04/03/1893,04/03/1897,Democratic,New York
+25,William McKinley,http://en.wikipedia.org/wiki/William_McKinley,04/03/1897,14/09/1901,Republican,Ohio
+26,Theodore Roosevelt,http://en.wikipedia.org/wiki/Theodore_Roosevelt,14/09/1901,04/03/1909,Republican,New York
+27,William Howard Taft,http://en.wikipedia.org/wiki/William_Howard_Taft,04/03/1909,04/03/1913,Republican,Ohio
+28,Woodrow Wilson,http://en.wikipedia.org/wiki/Woodrow_Wilson,04/03/1913,04/03/1921,Democratic,New Jersey
+29,Warren G. Harding,http://en.wikipedia.org/wiki/Warren_G._Harding,04/03/1921,02/08/1923,Republican,Ohio
+30,Calvin Coolidge,http://en.wikipedia.org/wiki/Calvin_Coolidge,02/08/1923,04/03/1929,Republican,Massachusetts
+31,Herbert Hoover,http://en.wikipedia.org/wiki/Herbert_Hoover,04/03/1929,04/03/1933,Republican,Iowa
+32,Franklin D. Roosevelt,http://en.wikipedia.org/wiki/Franklin_D._Roosevelt,04/03/1933,12/04/1945,Democratic,New York
+33,Harry S. Truman,http://en.wikipedia.org/wiki/Harry_S._Truman,12/04/1945,20/01/1953,Democratic,Missouri
+34,Dwight D. Eisenhower,http://en.wikipedia.org/wiki/Dwight_D._Eisenhower,20/01/1953,20/01/1961,Republican,Texas
+35,John F. Kennedy,http://en.wikipedia.org/wiki/John_F._Kennedy,20/01/1961,22/11/1963,Democratic,Massachusetts
+36,Lyndon B. Johnson,http://en.wikipedia.org/wiki/Lyndon_B._Johnson,22/11/1963,20/01/1969,Democratic,Texas
+37,Richard Nixon,http://en.wikipedia.org/wiki/Richard_Nixon,20/01/1969,09/08/1974,Republican,California
+38,Gerald Ford,http://en.wikipedia.org/wiki/Gerald_Ford,09/08/1974,20/01/1977,Republican,Michigan
+39,Jimmy Carter,http://en.wikipedia.org/wiki/Jimmy_Carter,20/01/1977,20/01/1981,Democratic,Georgia
+40,Ronald Reagan,http://en.wikipedia.org/wiki/Ronald_Reagan,20/01/1981,20/01/1989,Republican,California
+41,George H. W. Bush,http://en.wikipedia.org/wiki/George_H._W._Bush,20/01/1989,20/01/1993,Republican,Texas
+42,Bill Clinton,http://en.wikipedia.org/wiki/Bill_Clinton,20/01/1993,20/01/2001,Democratic,Arkansas
+43,George W. Bush,http://en.wikipedia.org/wiki/George_W._Bush,20/01/2001,20/01/2009,Republican,Texas
+44,Barack Obama,http://en.wikipedia.org/wiki/Barack_Obama,20/01/2009,Incumbent,  Democratic  ,Illinois
diff --git a/cassava.cabal b/cassava.cabal
--- a/cassava.cabal
+++ b/cassava.cabal
@@ -1,5 +1,5 @@
 Name:                cassava
-Version:             0.4.5.0
+Version:             0.4.5.1
 Synopsis:            A CSV parsing and encoding library
 Description:
   A CSV parsing and encoding library optimized for ease of use and high
@@ -16,9 +16,10 @@
 Category:            Text, Web, CSV
 Build-type:          Simple
 Cabal-version:       >=1.10
-Extra-source-files:  examples/*.hs,
+Extra-source-files:  benchmarks/*.csv,
+                     examples/*.hs,
                      CHANGES.md
-Tested-with:         GHC ==8.0.1, GHC ==7.10.3, GHC ==7.8.4, GHC ==7.6.3
+Tested-with:         GHC ==8.0.1, GHC ==7.10.3, GHC ==7.8.4, GHC ==7.6.3, GHC ==7.4.2
 
 Library
   default-language: Haskell2010
@@ -39,6 +40,11 @@
     TypeOperators
     UndecidableInstances
 
+  if impl(ghc >= 8.0)
+    other-extensions:
+      DataKinds
+      PolyKinds
+
   Exposed-modules:
     Data.Csv
     Data.Csv.Builder
@@ -56,7 +62,7 @@
   Build-depends:
     array < 0.6,
     attoparsec >= 0.10.2 && < 0.14,
-    base >= 4.6 && < 5,
+    base >= 4.5 && < 5,
     blaze-builder < 0.5,
     bytestring < 0.11,
     containers < 0.6,
@@ -66,6 +72,10 @@
     unordered-containers < 0.3,
     vector < 0.12
 
+  -- GHC.Generics lived in `ghc-prim` for GHC 7.2 & GHC 7.4 only
+  if impl(ghc < 7.6)
+    build-depends: ghc-prim == 0.2.*
+
   ghc-options: -Wall -O2
 
 Test-suite unit-tests
@@ -75,7 +85,7 @@
   Main-is: UnitTests.hs
   Build-depends:
     attoparsec,
-    base >= 4.6,
+    base >= 4.5,
     bytestring,
     cassava,
     hashable < 1.3,
@@ -111,7 +121,7 @@
   Build-depends:
     array < 0.6,
     attoparsec >= 0.10.2 && < 0.14,
-    base >= 4.6 && < 5,
+    base >= 4.5 && < 5,
     blaze-builder < 0.5,
     bytestring < 0.11,
     containers < 0.6,
@@ -123,6 +133,10 @@
     text,
     unordered-containers < 0.3,
     vector < 0.12
+
+  -- GHC.Generics lived in `ghc-prim` for GHC 7.2 & GHC 7.4 only
+  if impl(ghc < 7.6)
+    build-depends: ghc-prim == 0.2.*
 
   ghc-options: -Wall -O2