diff --git a/CHANGELOG.md b/CHANGELOG.md
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+## 0.1 [2021.08.29]
+* Backport the `Eq` and `Ord` instances for `BigNat`.
diff --git a/README.md b/README.md
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+# `ghc-bignum-orphans`
+[![Hackage](https://img.shields.io/hackage/v/ghc-bignum-orphans.svg)][Hackage: ghc-bignum-orphans]
+[![Hackage Dependencies](https://img.shields.io/hackage-deps/v/ghc-bignum-orphans.svg)](http://packdeps.haskellers.com/reverse/ghc-bignum-orphans)
+[![Haskell Programming Language](https://img.shields.io/badge/language-Haskell-blue.svg)][Haskell.org]
+[![BSD3 License](http://img.shields.io/badge/license-BSD3-brightgreen.svg)][tl;dr Legal: BSD3]
+[![Build Status](https://github.com/haskell-compat/ghc-bignum-orphans/workflows/Haskell-CI/badge.svg)](https://github.com/haskell-compat/ghc-bignum-orphans/actions?query=workflow%3AHaskell-CI)
+
+[Hackage: ghc-bignum-orphans]:
+  http://hackage.haskell.org/package/ghc-bignum-orphans
+  "ghc-bignum-orphans package on Hackage"
+[Haskell.org]:
+  http://www.haskell.org
+  "The Haskell Programming Language"
+[tl;dr Legal: BSD3]:
+  https://tldrlegal.com/license/bsd-3-clause-license-%28revised%29
+  "BSD 3-Clause License (Revised)"
+
+`ghc-bignum-orphans` defines orphan instances that mimic instances available in
+later versions of `ghc-bignum` to a wider (older) range of compilers.
+`ghc-bignum-orphans` does not export anything except the orphan instances themselves.
diff --git a/ghc-bignum-orphans.cabal b/ghc-bignum-orphans.cabal
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+cabal-version:      2.4
+name:               ghc-bignum-orphans
+version:            0.1
+synopsis:           Backwards-compatible orphan instances for ghc-bignum
+description:        @ghc-bignum-orphans@ defines orphan instances that mimic
+                    instances available in later versions of @ghc-bignum@ to a
+                    wider (older) range of compilers. @ghc-bignum-orphans@ does
+                    not export anything except the orphan instances themselves.
+homepage:           https://github.com/haskell-compat/ghc-bignum-orphans
+bug-reports:        https://github.com/haskell-compat/ghc-bignum-orphans/issues
+license:            BSD-3-Clause
+author:             Ryan Scott
+maintainer:         Ryan Scott <ryan.gl.scott@gmail.com>
+copyright:          (C) 2021 Ryan Scott
+category:           Compatibility
+extra-source-files: CHANGELOG.md, README.md
+tested-with:        GHC == 9.0.1
+                     || == 9.2.*
+
+source-repository head
+  type:               git
+  location:           https://github.com/haskell-compat/ghc-bignum-orphans
+
+library
+    exposed-modules:  GHC.Num.Orphans
+    build-depends:    base       >= 4.15 && < 5
+                    , ghc-bignum >= 1.0  && < 1.3
+    hs-source-dirs:   src
+    default-language: Haskell2010
+    ghc-options:      -Wall -Wcompat
diff --git a/src/GHC/Num/Orphans.hs b/src/GHC/Num/Orphans.hs
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+{-# LANGUAGE CPP #-}
+{-# LANGUAGE MagicHash #-}
+{-# OPTIONS_GHC -Wno-orphans #-}
+{-|
+Exports orphan instances that mimic instances available in later versions of
+@ghc-bignum@. To use them, simply @import GHC.Num.Orphans ()@.
+-}
+module GHC.Num.Orphans () where
+
+#if !(MIN_VERSION_ghc_bignum(1,1,0))
+import GHC.Num.BigNat
+#endif
+
+#if !(MIN_VERSION_ghc_bignum(1,1,0))
+instance Eq BigNat where
+   BN# a == BN# b = bigNatEq a b
+   BN# a /= BN# b = bigNatNe a b
+
+instance Ord BigNat where
+   (BN# a) `compare` (BN# b) = bigNatCompare a b
+   BN# a <  BN# b = bigNatLt a b
+   BN# a <= BN# b = bigNatLe a b
+   BN# a >  BN# b = bigNatGt a b
+   BN# a >= BN# b = bigNatGe a b
+#endif