diff --git a/.travis.yml b/.travis.yml
index abc5220..b52f862 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,8 +2,8 @@ language: julia
 os:
   - linux
 julia:
-  - 0.5
-  - 0.6
+  - 0.7
+  - 1.0
   - nightly
 notifications:
   email: false
diff --git a/REQUIRE b/REQUIRE
index a4c0f68..d0177bd 100644
--- a/REQUIRE
+++ b/REQUIRE
@@ -1,4 +1,4 @@
-julia 0.5
+julia 0.7
 Gtk
 GtkReactive 0.0.3
 Cairo 0.5.1
diff --git a/src/ProfileView.jl b/src/ProfileView.jl
index 7466e63..8946bfe 100644
--- a/src/ProfileView.jl
+++ b/src/ProfileView.jl
@@ -2,9 +2,10 @@ __precompile__()
 
 module ProfileView
 
+using Profile
 using Colors
 
-import Base: contains, isequal, show, mimewritable
+import Base: isequal, show
 
 include("tree.jl")
 include("pvtree.jl")
@@ -14,13 +15,13 @@ using .PVTree
 
 include("svgwriter.jl")
 
-immutable TagData
+struct TagData
     ip::UInt
     status::Int
 end
 const TAGNONE = TagData(UInt(0), -1)
 
-type ProfileData
+mutable struct ProfileData
     img
     lidict
     imgtags
@@ -33,32 +34,32 @@ const gccolor = colorant"red"
 const colors = distinguishable_colors(13, [bkg,fontcolor,gccolor],
                                       lchoices=Float64[65, 70, 75, 80],
                                       cchoices=Float64[0, 50, 60, 70],
-                                      hchoices=linspace(0, 330, 24))[4:end]
+                                      hchoices=range(0, stop=330, length=24))[4:end]
 
 function have_display()
-    !is_unix() && return true
-    is_apple() && return true
+    !Sys.isunix() && return true
+    Sys.isapple() && return true
     return haskey(ENV, "DISPLAY")
 end
 
 function __init__()
-    push!(LOAD_PATH, splitdir(@__FILE__)[1])
+    push!(LOAD_PATH, @__DIR__)
     if (isdefined(Main, :IJulia) && !isdefined(Main, :PROFILEVIEW_USEGTK)) || !have_display()
-        eval(Expr(:import, :ProfileViewSVG))
+        @eval import ProfileViewSVG
         @eval begin
             view(data = Profile.fetch(); C = false, lidict = nothing, colorgc = true, fontsize = 12, combine = true, pruned = []) = ProfileViewSVG.view(data; C=C, lidict=lidict, colorgc=colorgc, fontsize=fontsize, combine=combine, pruned=pruned)
         end
     else
-        eval(Expr(:import, :ProfileViewGtk))
+        @eval import ProfileViewGtk
         @eval begin
             view(data = Profile.fetch(); C = false, lidict = nothing, colorgc = true, fontsize = 12, combine = true, pruned = []) = ProfileViewGtk.view(data; C=C, lidict=lidict, colorgc=colorgc, fontsize=fontsize, combine=combine, pruned=pruned)
 
-            closeall() = ProfileViewGtk.closeall()
             @doc """
     closeall()
 
 Closes all windows opened by ProfileView.
-""" -> closeall
+"""
+            closeall() = ProfileViewGtk.closeall()
         end
     end
     pop!(LOAD_PATH)
@@ -70,7 +71,7 @@ function prepare(data; C = false, lidict = nothing, colorgc = true, combine = tr
 end
 
 function prepare_data(data, lidict)
-    bt, counts = Profile.tree_aggregate(data)
+    bt, counts = tree_aggregate(data)
     if isempty(counts)
         Profile.warning_empty()
         error("Nothing to view")
@@ -97,7 +98,7 @@ function prepare_data(data, lidict)
     # Do code address lookups on all unique instruction pointers
     uip = unique(vcat(bt...))
     if lidict == nothing
-        lkup = Vector{StackFrame}[Profile.lookup(ip) for ip in uip]
+        lkup = Vector{StackTraces.StackFrame}[Profile.lookup(ip) for ip in uip]
         lidict = Dict(zip(uip, lkup))
     else
         lkup = [lidict[ip] for ip in uip]
@@ -105,7 +106,7 @@ function prepare_data(data, lidict)
     bt, uip, counts, lidict, lkup
 end
 
-prepare_data(::Void, ::Void) = nothing, nothing, nothing, nothing, nothing
+prepare_data(::Nothing, ::Nothing) = nothing, nothing, nothing, nothing, nothing
 
 function prepare_image(bt, uip, counts, lidict, lkup, C, colorgc, combine,
                        pruned)
@@ -170,7 +171,7 @@ function svgwrite(filename::AbstractString; kwargs...)
 end
 
 
-mimewritable(::MIME"image/svg+xml", pd::ProfileData) = true
+Base.showable(::MIME"image/svg+xml", pd::ProfileData) = true
 
 function show(f::IO, ::MIME"image/svg+xml", pd::ProfileData)
     img = pd.img
@@ -267,7 +268,7 @@ function buildtags!(rowtags, parent, level)
     end
     t = rowtags[level]
     for c in parent
-        t[c.data.hspan] = TagData(c.data.ip, c.data.status)
+        t[c.data.hspan] .= Ref(TagData(c.data.ip, c.data.status))
         buildtags!(rowtags, c, level+1)
     end
 end
@@ -318,10 +319,10 @@ end
 
 function fillrow!(img, j, rng::UnitRange{Int}, colorindex, colorlen, regcolor, gccolor, status)
     if status > 0
-        img[rng,j] = gccolor
+        img[rng,j] .= gccolor
         return colorindex
     else
-        img[rng,j] = regcolor
+        img[rng,j] .= regcolor
         return mod1(colorindex+1, colorlen)
     end
 end
@@ -407,4 +408,27 @@ function pushpruned!(pruned_ips, pruned, lidict)
     end
 end
 
+## A tree representation
+# Identify and counts repetitions of all unique backtraces
+function tree_aggregate(data::Vector{UInt64})
+    iz = findall(iszero, data)  # find the breaks between backtraces
+    treecount = Dict{Vector{UInt64},Int}()
+    istart = 1
+    for iend in iz
+        tmp = data[iend - 1 : -1 : istart]
+        treecount[tmp] = get(treecount, tmp, 0) + 1
+        istart = iend + 1
+    end
+    bt = Vector{Vector{UInt64}}(undef, 0)
+    counts = Vector{Int}(undef, 0)
+    for (k, v) in treecount
+        if !isempty(k)
+            push!(bt, k)
+            push!(counts, v)
+        end
+    end
+    return (bt, counts)
+end
+
+
 end
diff --git a/src/ProfileViewGtk.jl b/src/ProfileViewGtk.jl
index 227c8a5..a90b31e 100644
--- a/src/ProfileViewGtk.jl
+++ b/src/ProfileViewGtk.jl
@@ -8,13 +8,13 @@ using Graphics
 
 using Gtk.GConstants.GdkModifierType: SHIFT, CONTROL, MOD1
 
-type ZoomCanvas
+mutable struct ZoomCanvas
     bb::BoundingBox  # in user-coordinates
     c::Canvas
 end
 
 function __init__()
-    eval(Expr(:import, :ProfileView))
+    @eval import ProfileView
 end
 
 function closeall()
@@ -24,13 +24,13 @@ function closeall()
     nothing
 end
 
-const window_wrefs = WeakKeyDict{Gtk.GtkWindowLeaf,Void}()
+const window_wrefs = WeakKeyDict{Gtk.GtkWindowLeaf,Nothing}()
 
 function view(data = Profile.fetch(); lidict=nothing, kwargs...)
     bt, uip, counts, lidict, lkup = ProfileView.prepare_data(data, lidict)
     # Display in a window
     c = canvas(UserUnit)
-    setproperty!(widget(c), :expand, true)
+    set_gtk_property!(widget(c), :expand, true)
     f = Frame(c)
     tb = Toolbar()
     bx = Box(:v)
@@ -40,8 +40,8 @@ function view(data = Profile.fetch(); lidict=nothing, kwargs...)
     tb_save_as = ToolButton("gtk-save-as")
     push!(tb, tb_open)
     push!(tb, tb_save_as)
-    signal_connect(open_cb, tb_open, "clicked", Void, (), false, (widget(c),kwargs))
-    signal_connect(save_as_cb, tb_save_as, "clicked", Void, (), false, (widget(c),data,lidict,kwargs))
+    signal_connect(open_cb, tb_open, "clicked", Nothing, (), false, (widget(c),kwargs))
+    signal_connect(save_as_cb, tb_save_as, "clicked", Nothing, (), false, (widget(c),data,lidict,kwargs))
     win = Window(bx, "Profile")
     GtkReactive.gc_preserve(win, c)
     # Register the window with closeall
@@ -57,17 +57,17 @@ function view(data = Profile.fetch(); lidict=nothing, kwargs...)
     # Ctrl-w and Ctrl-q destroy the window
     signal_connect(win, "key-press-event") do w, evt
         if evt.state == CONTROL && (evt.keyval == UInt('q') || evt.keyval == UInt('w'))
-            @schedule destroy(w)
+            @async destroy(w)
             nothing
         end
     end
 
-    showall(win)
+    Gtk.showall(win)
 end
 
 function viewprof(c, bt, uip, counts, lidict, lkup; C = false, colorgc = true, fontsize = 12, combine = true, pruned=[])
     img, lidict, imgtags = ProfileView.prepare_image(bt, uip, counts, lidict, lkup, C, colorgc, combine, pruned)
-    img24 = UInt32[reinterpret(UInt32, convert(RGB24, img[i,j])) for i = 1:size(img,1), j = size(img,2):-1:1]'
+    img24 = Matrix(UInt32[reinterpret(UInt32, convert(RGB24, img[i,j])) for i = 1:size(img,1), j = size(img,2):-1:1]')
     fv = XY(0.0..size(img24,2), 0.0..size(img24,1))
     zr = Signal(ZoomRegion(fv, fv))
     sigrb = init_zoom_rubberband(c, zr)
diff --git a/src/ProfileViewSVG.jl b/src/ProfileViewSVG.jl
index e8c8e07..cb9b498 100644
--- a/src/ProfileViewSVG.jl
+++ b/src/ProfileViewSVG.jl
@@ -3,7 +3,7 @@ __precompile__()
 module ProfileViewSVG
 
 function __init__()
-    eval(Expr(:import, :ProfileView))
+    @eval import ProfileView
 end
 
 function view(data = Profile.fetch(); C = false, lidict = nothing, colorgc = true, fontsize = 12, combine = true, pruned = true)
diff --git a/src/pvtree.jl b/src/pvtree.jl
index 7a60cae..d48b257 100644
--- a/src/pvtree.jl
+++ b/src/pvtree.jl
@@ -5,7 +5,7 @@ using ..Tree
 export PVData, buildgraph!, prunegraph!
 
 # ProfileView data we need attached to each node of the graph:
-type PVData
+mutable struct PVData
     ip::UInt           # the instruction pointer
     hspan::UnitRange{Int} # horizontal span (used as the x-axis in display)
     status::Int        # nonzero for special handling, (e.g., gc events)
@@ -37,9 +37,9 @@ function buildgraph!(parent::Node, bt::Vector{Vector{UInt}}, counts::Vector{Int}
         end
     end
     ngroups = length(dorder)
-    group = Vector{Vector{Int}}(ngroups)  # indices in bt that have the same sortorder
-    n = Array{Int}(ngroups)              # aggregated counts for this group
-    order = Array{Int}(ngroups)
+    group = Vector{Vector{Int}}(undef, ngroups)  # indices in bt that have the same sortorder
+    n = Array{Int}(undef, ngroups)              # aggregated counts for this group
+    order = Array{Int}(undef, ngroups)
     i = 1
     for (key, v) in dorder
         order[i] = key
diff --git a/src/svgwriter.jl b/src/svgwriter.jl
index e6e115d..fed5f0d 100644
--- a/src/svgwriter.jl
+++ b/src/svgwriter.jl
@@ -1,5 +1,5 @@
-const snapsvgjs = joinpath(dirname(@__FILE__), "..", "templates", "snap.svg-min.js")
-const viewerjs = joinpath(dirname(@__FILE__), "viewer.js")
+const snapsvgjs = joinpath(@__DIR__, "..", "templates", "snap.svg-min.js")
+const viewerjs = joinpath(@__DIR__, "viewer.js")
 
 function escape_script(js::AbstractString)
     return replace(js, "]]", "] ]")
diff --git a/src/tree.jl b/src/tree.jl
index ea8da73..d1f23ae 100644
--- a/src/tree.jl
+++ b/src/tree.jl
@@ -1,6 +1,6 @@
 module Tree
 
-import Base: start, done, next, show
+import Base: iterate, show
 
 export Node,
     addchild,
@@ -16,14 +16,14 @@ export Node,
 #     Any missing links (e.g., "c" does not have a sibling) link back to itself (c.sibling == c)
 # With this organization, no arrays need to be allocated.
 
-type Node{T}
+mutable struct Node{T}
     data::T
     parent::Node{T}
     child::Node{T}
     sibling::Node{T}
     
     # Constructor for the root of the tree
-    function (::Type{Node{T}}){T}(data::T)
+    function Node{T}(data) where T
         n = new{T}(data)
         n.parent = n
         n.child = n
@@ -31,15 +31,15 @@ type Node{T}
         n
     end
     # Constructor for all others
-    function (::Type{Node{T}}){T}(data::T, parent::Node)
+    function Node{T}(data, parent::Node) where T
         n = new{T}(data, parent)
         n.child = n
         n.sibling = n
         n
     end
 end
-Node{T}(data::T) = Node{T}(data)
-Node{T}(data::T, parent::Node{T}) = Node{T}(data, parent)
+Node(data::T) where {T} = Node{T}(data)
+Node(data, parent::Node{T}) where {T} = Node{T}(data, parent)
 
 function lastsibling(sib::Node)
     newsib = sib.sibling
@@ -50,7 +50,7 @@ function lastsibling(sib::Node)
     sib
 end
 
-function addsibling{T}(oldersib::Node{T}, data::T)
+function addsibling(oldersib::Node{T}, data) where T
     if oldersib.sibling != oldersib
         error("Truncation of sibling list")
     end
@@ -59,7 +59,7 @@ function addsibling{T}(oldersib::Node{T}, data::T)
     youngersib
 end
 
-function addchild{T}(parent::Node{T}, data::T)
+function addchild(parent::Node{T}, data) where T
     newc = Node(data, parent)
     prevc = parent.child
     if prevc == parent
@@ -80,9 +80,10 @@ show(io::IO, n::Node) = print(io, n.data)
 # for c in parent
 #     # do something
 # end
-start(n::Node) = n.child
-done(n::Node, state::Node) = n == state
-next(n::Node, state::Node) = state, state == state.sibling ? n : state.sibling
+function iterate(n::Node, state = n.child)
+    n == state && return nothing
+    return state, state == state.sibling ? n : state.sibling
+end
 
 function showedges(io::IO, parent::Node, printfunc = identity)
     str = printfunc(parent.data)
diff --git a/test/test.jl b/test/test.jl
index efc9b5a..222d9fc 100644
--- a/test/test.jl
+++ b/test/test.jl
@@ -1,13 +1,13 @@
+using Profile
 using ProfileView
 
 function profile_test(n)
     for i = 1:n
         A = randn(100,100,20)
         m = maximum(A)
-        Afft = fft(A)
-        Am = mapslices(sum, A, 2)
+        Am = mapslices(sum, A, dims = 2)
         B = A[:,:,5]
-        Bsort = mapslices(sort, B, 1)
+        Bsort = mapslices(sort, B, dims = 1)
         b = rand(100)
         C = B.*b
     end
diff --git a/test/tree.jl b/test/tree.jl
index c84f70e..5d1e40d 100644
--- a/test/tree.jl
+++ b/test/tree.jl
@@ -3,7 +3,7 @@ root = Tree.Node(0)
 @assert Tree.isleaf(root)
 nchildren = 0
 for c in root
-    nchildren += 1
+    global nchildren += 1
 end
 @assert nchildren == 0
 c1 = Tree.addchild(root, 1)
@@ -17,7 +17,7 @@ c22 = Tree.addchild(c2, 5)
 nchildren = 0
 for c in root
     @assert !Tree.isroot(c)
-    nchildren += 1
+    global nchildren += 1
 end
 @assert nchildren == 3
 @assert Tree.isleaf(c1)
@@ -30,5 +30,6 @@ end
 children2 = [c21,c22]
 i = 0
 for c in c2
+    global i
     @assert c == children2[i+=1]
 end