diff --git a/.travis.yml b/.travis.yml
index 868e9a2..2550a73 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,7 +3,7 @@ os:
     - osx
     - linux
 julia:
-    - 0.6
+    - 0.7
     - nightly
 notifications:
     email: false
diff --git a/README.md b/README.md
index e44cca3..eac6839 100644
--- a/README.md
+++ b/README.md
@@ -39,7 +39,7 @@ JSON.print(io::IO, s::AbstractString)
 JSON.print(io::IO, s::Union{Integer, AbstractFloat})
 JSON.print(io::IO, n::Nothing)
 JSON.print(io::IO, b::Bool)
-JSON.print(io::IO, a::Associative)
+JSON.print(io::IO, a::AbstractDict)
 JSON.print(io::IO, v::AbstractVector)
 JSON.print{T, N}(io::IO, v::Array{T, N})
 ```
@@ -48,8 +48,8 @@ Writes a compact (no extra whitespace or indentation) JSON representation
 to the supplied IO.
 
 ```julia
-JSON.print(a::Associative, indent)
-JSON.print(io::IO, a::Associative, indent)
+JSON.print(a::AbstractDict, indent)
+JSON.print(io::IO, a::AbstractDict, indent)
 ```
 
 Writes a JSON representation with newlines, and indentation if specified. Non-zero `indent` will be applied recursively to nested elements.
diff --git a/REQUIRE b/REQUIRE
index d71c8f0..cdbb2dc 100644
--- a/REQUIRE
+++ b/REQUIRE
@@ -1,3 +1 @@
-julia 0.6
-Compat 0.61.0
-Nullables 0.0.1
+julia 0.7-alpha
diff --git a/appveyor.yml b/appveyor.yml
index fde4cb5..de914ec 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,7 +1,7 @@
 environment:
   matrix:
-  - JULIA_URL: "https://julialang-s3.julialang.org/bin/winnt/x86/0.6/julia-0.6-latest-win32.exe"
-  - JULIA_URL: "https://julialang-s3.julialang.org/bin/winnt/x64/0.6/julia-0.6-latest-win64.exe"
+  - JULIA_URL: "https://julialang-s3.julialang.org/bin/winnt/x86/0.7/julia-0.7-latest-win32.exe"
+  - JULIA_URL: "https://julialang-s3.julialang.org/bin/winnt/x64/0.7/julia-0.7-latest-win64.exe"
   - JULIA_URL: "https://julialangnightlies-s3.julialang.org/bin/winnt/x86/julia-latest-win32.exe"
   - JULIA_URL: "https://julialangnightlies-s3.julialang.org/bin/winnt/x64/julia-latest-win64.exe"
 
diff --git a/src/Common.jl b/src/Common.jl
index 0e85706..55b1fe5 100644
--- a/src/Common.jl
+++ b/src/Common.jl
@@ -3,10 +3,7 @@ Internal implementation detail.
 """
 module Common
 
-using Compat
-if VERSION >= v"0.7.0-DEV.2915"
-    using Unicode
-end
+using Unicode
 
 include("bytes.jl")
 include("errors.jl")
diff --git a/src/JSON.jl b/src/JSON.jl
index b5f9e5b..4e5a01e 100644
--- a/src/JSON.jl
+++ b/src/JSON.jl
@@ -2,8 +2,6 @@ __precompile__()
 
 module JSON
 
-using Compat
-
 export json # returns a compact (or indented) JSON representation as a string
 export JSONText # string wrapper to insert raw JSON into JSON output
 
diff --git a/src/Parser.jl b/src/Parser.jl
index ac6ef2d..147d675 100644
--- a/src/Parser.jl
+++ b/src/Parser.jl
@@ -1,8 +1,6 @@
 module Parser  # JSON
 
-using Compat
-using Compat.Mmap
-using Nullables
+using Mmap
 using ..Common
 
 """
@@ -312,8 +310,9 @@ byte before `to`. Bytes enclosed should all be ASCII characters.
 function float_from_bytes(bytes, from::Int, to::Int)
     # The ccall is not ideal (Base.tryparse would be better), but it actually
     # makes an 2× difference to performance
-    ccall(:jl_try_substrtod, Nullable{Float64},
+    hasvalue, val = ccall(:jl_try_substrtod, Tuple{Bool, Float64},
             (Ptr{UInt8}, Csize_t, Csize_t), bytes, from - 1, to - from + 1)
+    hasvalue ? val : nothing
 end
 
 """
@@ -350,7 +349,7 @@ function number_from_bytes(pc::ParserContext,
         int_from_bytes(pc, ps, bytes, from, to)
     else
         res = float_from_bytes(bytes, from, to)
-        isnull(res) ? _error(E_BAD_NUMBER, ps) : get(res)
+        res === nothing ? _error(E_BAD_NUMBER, ps) : res
     end
 end
 
diff --git a/src/Writer.jl b/src/Writer.jl
index 7335f5b..d60dcbd 100644
--- a/src/Writer.jl
+++ b/src/Writer.jl
@@ -1,15 +1,11 @@
 module Writer
 
-using Compat
-using Compat.Dates
-using Nullables
+using Dates
 using ..Common
 using ..Serializations: Serialization, StandardSerialization,
                         CommonSerialization
 
-if VERSION >= v"0.7.0-DEV.2915"
-    using Unicode
-end
+using Unicode
 
 
 """
@@ -268,14 +264,6 @@ end
 
 show_json(io::SC, ::CS, ::Nothing) = show_null(io)
 
-function show_json(io::SC, s::CS, a::Nullable)
-    if isnull(a)
-        Base.print(io, "null")
-    else
-        show_json(io, s, get(a))
-    end
-end
-
 function show_json(io::SC, s::CS, a::AbstractDict)
     begin_object(io)
     for kv in a
@@ -313,7 +301,7 @@ Serialize a multidimensional array to JSON in column-major format. That is,
 function show_json(io::SC, s::CS, A::AbstractArray{<:Any,n}) where n
     begin_array(io)
     newdims = ntuple(_ -> :, n - 1)
-    for j in Compat.axes(A, n)
+    for j in axes(A, n)
         show_element(io, s, view(A, newdims..., j))
     end
     end_array(io)
diff --git a/src/bytes.jl b/src/bytes.jl
index a5f2768..57b92a8 100644
--- a/src/bytes.jl
+++ b/src/bytes.jl
@@ -53,11 +53,7 @@ for c in 0x00:0xFF
     elseif haskey(REVERSE_ESCAPES, c)
         [BACKSLASH, REVERSE_ESCAPES[c]]
     elseif iscntrl(Char(c)) || !isprint(Char(c))
-        if VERSION < v"0.7.0-DEV.4446"
-            UInt8[BACKSLASH, LATIN_U, hex(c, 4)...]
-        else
-            UInt8[BACKSLASH, LATIN_U, string(c, base=16, pad=4)...]
-        end
+        UInt8[BACKSLASH, LATIN_U, string(c, base=16, pad=4)...]
     else
         [c]
     end
diff --git a/src/specialized.jl b/src/specialized.jl
index f796e4e..dee81ba 100644
--- a/src/specialized.jl
+++ b/src/specialized.jl
@@ -1,9 +1,5 @@
 function maxsize_buffer(maxsize::Int)
-    @static if VERSION < v"0.7.0-DEV.3734"
-        IOBuffer(maxsize)
-    else
-        IOBuffer(maxsize=maxsize)
-    end
+    IOBuffer(maxsize=maxsize)
 end
 
 # Specialized functions for increased performance when JSON is in-memory
diff --git a/test/REQUIRE b/test/REQUIRE
index 4878360..d0dacdd 100644
--- a/test/REQUIRE
+++ b/test/REQUIRE
@@ -1,4 +1,3 @@
 DataStructures
 FixedPointNumbers
 OffsetArrays
-Compat 0.37.0
diff --git a/test/async.jl b/test/async.jl
index 6ef44e7..1612a6e 100644
--- a/test/async.jl
+++ b/test/async.jl
@@ -1,8 +1,6 @@
 finished_async_tests = RemoteChannel()
 
-if VERSION >= v"0.7.0-DEV.4442"
-    using Sockets
-end
+using Sockets
 
 @async begin
     s = listen(7777)
diff --git a/test/lowering.jl b/test/lowering.jl
index bf52c4b..388cff1 100644
--- a/test/lowering.jl
+++ b/test/lowering.jl
@@ -1,8 +1,8 @@
 module TestLowering
 
 using JSON
-using Compat.Test
-using Compat.Dates
+using Test
+using Dates
 using FixedPointNumbers: Fixed
 
 @test JSON.json(Date(2016, 8, 3)) == "\"2016-08-03\""
diff --git a/test/parser/parsefile.jl b/test/parser/parsefile.jl
index 07cc589..f5b9f6c 100644
--- a/test/parser/parsefile.jl
+++ b/test/parser/parsefile.jl
@@ -1,7 +1,7 @@
 tmppath, io = mktemp()
 write(io, facebook)
 close(io)
-if Compat.Sys.iswindows()
+if Sys.iswindows()
     # don't use mmap on Windows, to avoid ERROR: unlink: operation not permitted (EPERM)
     @test haskey(JSON.parsefile(tmppath; use_mmap=false), "data")
 else
diff --git a/test/runtests.jl b/test/runtests.jl
index fb4d1a1..e732e5d 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -1,8 +1,7 @@
 using JSON
-using Compat.Test
-using Compat
-using Compat.Dates
-using Compat.Distributed: RemoteChannel
+using Test
+using Dates
+using Distributed: RemoteChannel
 using OffsetArrays
 
 import DataStructures
diff --git a/test/serializer.jl b/test/serializer.jl
index 24b0b2e..87927fe 100644
--- a/test/serializer.jl
+++ b/test/serializer.jl
@@ -1,7 +1,7 @@
 module TestSerializer
 
 using JSON
-using Compat.Test
+using Test
 
 # to define a new serialization behaviour, import these first
 import JSON.Serializations: CommonSerialization, StandardSerialization
diff --git a/test/standard-serializer.jl b/test/standard-serializer.jl
index 07e37ab..034bfc4 100644
--- a/test/standard-serializer.jl
+++ b/test/standard-serializer.jl
@@ -1,5 +1,3 @@
-using Nullables
-
 @testset "Symbol" begin
     symtest = Dict(:symbolarray => [:apple, :pear], :symbolsingleton => :hello)
     @test (JSON.json(symtest) == "{\"symbolarray\":[\"apple\",\"pear\"],\"symbolsingleton\":\"hello\"}"
@@ -11,10 +9,10 @@ end
     @test sprint(JSON.print, [Inf]) == "[null]"
 end
 
-@testset "Nullable" begin
-    @test sprint(JSON.print, [Nullable()]) == "[null]"
-    @test sprint(JSON.print, [Nullable{Int64}()]) == "[null]"
-    @test sprint(JSON.print, [Nullable{Int64}(Int64(1))]) == "[1]"
+@testset "Union{Nothing,T} (old Nullable)" begin
+    @test sprint(JSON.print, Union{Any,Nothing}[nothing]) == "[null]"
+    @test sprint(JSON.print, Union{Int64,Nothing}[nothing]) == "[null]"
+    @test sprint(JSON.print, Union{Int64,Nothing}[1]) == "[1]"
 end
 
 @testset "Char" begin