diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index c74f759..effd47f 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -63,6 +63,8 @@ run `go mod tidy` to minimize such changes.
 
 - use `./internal/fsx.OpenFile` when you need to open a file
 
+- use `./internal/iox.ReadAllContext` instead of `ioutil.ReadAll`
+
 ## Code testing requirements
 
 Make sure all tests pass with `go test -race ./...` run from the
diff --git a/cmd/ooniprobe/internal/database/database.go b/cmd/ooniprobe/internal/database/database.go
index 9b59047..2589a8c 100644
--- a/cmd/ooniprobe/internal/database/database.go
+++ b/cmd/ooniprobe/internal/database/database.go
@@ -1,11 +1,12 @@
 package database
 
 import (
+	"context"
 	"database/sql"
 	"embed"
-	"io/ioutil"
 
 	"github.com/apex/log"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	migrate "github.com/rubenv/sql-migrate"
 	"upper.io/db.v3/lib/sqlbuilder"
 	"upper.io/db.v3/sqlite"
@@ -19,7 +20,7 @@ func readAsset(path string) ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
-	return ioutil.ReadAll(filep)
+	return iox.ReadAllContext(context.Background(), filep)
 }
 
 func readAssetDir(path string) ([]string, error) {
diff --git a/internal/cmd/jafar/badproxy/badproxy.go b/internal/cmd/jafar/badproxy/badproxy.go
index e3060c0..2eebb3f 100644
--- a/internal/cmd/jafar/badproxy/badproxy.go
+++ b/internal/cmd/jafar/badproxy/badproxy.go
@@ -6,16 +6,17 @@
 package badproxy
 
 import (
+	"context"
 	"crypto/rsa"
 	"crypto/tls"
 	"crypto/x509"
 	"io"
-	"io/ioutil"
 	"net"
 	"strings"
 	"time"
 
 	"github.com/google/martian/v3/mitm"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 // CensoringProxy is a proxy that does not behave correctly.
@@ -56,7 +57,7 @@ func (p *CensoringProxy) serve(conn net.Conn) {
 	} else {
 		const maxread = 1 << 17
 		reader := io.LimitReader(conn, maxread)
-		ioutil.ReadAll(reader)
+		iox.ReadAllContext(context.Background(), reader)
 	}
 	conn.Close()
 }
diff --git a/internal/cmd/jafar/httpproxy/httpproxy_test.go b/internal/cmd/jafar/httpproxy/httpproxy_test.go
index 8318ade..a701ce1 100644
--- a/internal/cmd/jafar/httpproxy/httpproxy_test.go
+++ b/internal/cmd/jafar/httpproxy/httpproxy_test.go
@@ -3,12 +3,12 @@ package httpproxy
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"testing"
 
 	"github.com/ooni/probe-cli/v3/internal/cmd/jafar/uncensored"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestPass(t *testing.T) {
@@ -89,7 +89,7 @@ func checkrequest(
 		t.Fatal("unexpected value of status code")
 	}
 	t.Log(resp)
-	values, _ := resp.Header["Via"]
+	values := resp.Header["Via"]
 	var foundProduct bool
 	for _, value := range values {
 		if value == product {
@@ -102,7 +102,7 @@ func checkrequest(
 	if !foundProduct && expectVia {
 		t.Fatal("Via header not found")
 	}
-	proxiedData, err := ioutil.ReadAll(resp.Body)
+	proxiedData, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -120,7 +120,7 @@ func checkbody(t *testing.T, proxiedData []byte, host string) {
 		t.Fatal("unexpected status code")
 	}
 	defer resp.Body.Close()
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/cmd/jafar/uncensored/uncensored_test.go b/internal/cmd/jafar/uncensored/uncensored_test.go
index b58c055..731318c 100644
--- a/internal/cmd/jafar/uncensored/uncensored_test.go
+++ b/internal/cmd/jafar/uncensored/uncensored_test.go
@@ -3,10 +3,11 @@ package uncensored
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"testing"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestGood(t *testing.T) {
@@ -55,7 +56,7 @@ func TestGood(t *testing.T) {
 	if resp.StatusCode != 200 {
 		t.Fatal("invalid status-code")
 	}
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/cmd/oohelper/internal/client.go b/internal/cmd/oohelper/internal/client.go
index 74d665f..468b284 100644
--- a/internal/cmd/oohelper/internal/client.go
+++ b/internal/cmd/oohelper/internal/client.go
@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
@@ -15,6 +14,7 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine/experiment/webconnectivity"
 	"github.com/ooni/probe-cli/v3/internal/engine/httpheader"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/runtimex"
 	"github.com/ooni/probe-cli/v3/internal/version"
 )
@@ -126,7 +126,7 @@ func (oo OOClient) Do(ctx context.Context, config OOConfig) (*CtrlResponse, erro
 	if resp.StatusCode != 200 {
 		return nil, ErrHTTPStatusCode
 	}
-	data, err = ioutil.ReadAll(resp.Body)
+	data, err = iox.ReadAllContext(ctx, resp.Body)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/cmd/oohelper/internal/fake_test.go b/internal/cmd/oohelper/internal/fake_test.go
index 13bcdb9..df7987b 100644
--- a/internal/cmd/oohelper/internal/fake_test.go
+++ b/internal/cmd/oohelper/internal/fake_test.go
@@ -3,13 +3,13 @@ package internal
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"time"
 
 	"github.com/ooni/probe-cli/v3/internal/atomicx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeResolver struct {
@@ -63,7 +63,7 @@ func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return txp.Func(req)
 	}
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/cmd/oohelperd/internal/fake_test.go b/internal/cmd/oohelperd/internal/fake_test.go
index 95abe2c..46c2654 100644
--- a/internal/cmd/oohelperd/internal/fake_test.go
+++ b/internal/cmd/oohelperd/internal/fake_test.go
@@ -3,13 +3,13 @@ package internal
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"time"
 
 	"github.com/ooni/probe-cli/v3/internal/atomicx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeResolver struct {
@@ -63,7 +63,7 @@ func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return txp.Func(req)
 	}
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/cmd/oohelperd/internal/http.go b/internal/cmd/oohelperd/internal/http.go
index 3985c44..3f25bf8 100644
--- a/internal/cmd/oohelperd/internal/http.go
+++ b/internal/cmd/oohelperd/internal/http.go
@@ -3,12 +3,12 @@ package internal
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"strings"
 	"sync"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/experiment/webconnectivity"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 // CtrlHTTPResponse is the result of the HTTP check performed by
@@ -56,7 +56,7 @@ func HTTPDo(ctx context.Context, config *HTTPConfig) {
 		headers[k] = resp.Header.Get(k)
 	}
 	reader := &io.LimitedReader{R: resp.Body, N: config.MaxAcceptableBody}
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	config.Out <- CtrlHTTPResponse{
 		BodyLength: int64(len(data)),
 		Failure:    newfailure(err),
diff --git a/internal/cmd/oohelperd/internal/internal.go b/internal/cmd/oohelperd/internal/internal.go
index 35adad6..0bf5b44 100644
--- a/internal/cmd/oohelperd/internal/internal.go
+++ b/internal/cmd/oohelperd/internal/internal.go
@@ -4,10 +4,10 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/netx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/version"
 )
 
@@ -32,7 +32,7 @@ func (h Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		return
 	}
 	reader := &io.LimitedReader{R: req.Body, N: h.MaxAcceptableBody}
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(req.Context(), reader)
 	if err != nil {
 		w.WriteHeader(400)
 		return
@@ -42,12 +42,7 @@ func (h Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		w.WriteHeader(400)
 		return
 	}
-	measureConfig := MeasureConfig{
-		Client:            h.Client,
-		Dialer:            h.Dialer,
-		MaxAcceptableBody: h.MaxAcceptableBody,
-		Resolver:          h.Resolver,
-	}
+	measureConfig := MeasureConfig(h)
 	cresp, err := Measure(req.Context(), measureConfig, &creq)
 	if err != nil {
 		w.WriteHeader(400)
diff --git a/internal/cmd/oohelperd/internal/internal_test.go b/internal/cmd/oohelperd/internal/internal_test.go
index 1064f24..34cdffd 100644
--- a/internal/cmd/oohelperd/internal/internal_test.go
+++ b/internal/cmd/oohelperd/internal/internal_test.go
@@ -1,9 +1,9 @@
 package internal_test
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/http/httptest"
@@ -12,6 +12,7 @@ import (
 
 	"github.com/ooni/probe-cli/v3/internal/cmd/oohelperd/internal"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/resolver"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 const simplerequest = `{
@@ -126,7 +127,7 @@ func TestWorkingAsIntended(t *testing.T) {
 			if v := resp.Header.Get("content-type"); v != expect.respContentType {
 				t.Fatalf("unexpected content-type: %s", v)
 			}
-			data, err := ioutil.ReadAll(resp.Body)
+			data, err := iox.ReadAllContext(context.Background(), resp.Body)
 			if err != nil {
 				t.Fatal(err)
 			}
diff --git a/internal/engine/experiment/dash/collect.go b/internal/engine/experiment/dash/collect.go
index 9e15dcc..641e222 100644
--- a/internal/engine/experiment/dash/collect.go
+++ b/internal/engine/experiment/dash/collect.go
@@ -16,7 +16,7 @@ type collectDeps interface {
 	JSONMarshal(v interface{}) ([]byte, error)
 	Logger() model.Logger
 	NewHTTPRequest(method string, url string, body io.Reader) (*http.Request, error)
-	ReadAll(r io.Reader) ([]byte, error)
+	ReadAllContext(ctx context.Context, r io.Reader) ([]byte, error)
 	Scheme() string
 	UserAgent() string
 }
@@ -47,7 +47,7 @@ func collect(ctx context.Context, fqdn, authorization string,
 		return errHTTPRequestFailed
 	}
 	defer resp.Body.Close()
-	data, err = deps.ReadAll(resp.Body)
+	data, err = deps.ReadAllContext(ctx, resp.Body)
 	if err != nil {
 		return err
 	}
diff --git a/internal/engine/experiment/dash/dash.go b/internal/engine/experiment/dash/dash.go
index 5b285bd..08313b3 100644
--- a/internal/engine/experiment/dash/dash.go
+++ b/internal/engine/experiment/dash/dash.go
@@ -9,7 +9,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"runtime"
 	"time"
@@ -20,6 +19,7 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/errorx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/trace"
 	"github.com/ooni/probe-cli/v3/internal/humanize"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 const (
@@ -86,8 +86,8 @@ func (r runner) NewHTTPRequest(meth, url string, body io.Reader) (*http.Request,
 	return http.NewRequest(meth, url, body)
 }
 
-func (r runner) ReadAll(reader io.Reader) ([]byte, error) {
-	return ioutil.ReadAll(reader)
+func (r runner) ReadAllContext(ctx context.Context, reader io.Reader) ([]byte, error) {
+	return iox.ReadAllContext(ctx, reader)
 }
 
 func (r runner) Scheme() string {
@@ -179,7 +179,7 @@ func (r runner) measure(
 		current.ConnectTime = connectTime
 		r.tk.ReceiverData = append(r.tk.ReceiverData, current)
 		total += current.Received
-		avgspeed := 8 * float64(total) / time.Now().Sub(begin).Seconds()
+		avgspeed := 8 * float64(total) / time.Since(begin).Seconds()
 		percentage := float64(current.Iteration) / float64(numIterations)
 		message := fmt.Sprintf("streaming: speed: %s", humanize.SI(avgspeed, "bit/s"))
 		r.callbacks.OnProgress(percentage, message)
diff --git a/internal/engine/experiment/dash/download.go b/internal/engine/experiment/dash/download.go
index 1d860d2..02574d7 100644
--- a/internal/engine/experiment/dash/download.go
+++ b/internal/engine/experiment/dash/download.go
@@ -12,7 +12,7 @@ import (
 type downloadDeps interface {
 	HTTPClient() *http.Client
 	NewHTTPRequest(method string, url string, body io.Reader) (*http.Request, error)
-	ReadAll(r io.Reader) ([]byte, error)
+	ReadAllContext(ctx context.Context, r io.Reader) ([]byte, error)
 	Scheme() string
 	UserAgent() string
 }
@@ -57,7 +57,7 @@ func download(ctx context.Context, config downloadConfig) (downloadResult, error
 		return result, errHTTPRequestFailed
 	}
 	defer resp.Body.Close()
-	data, err := config.deps.ReadAll(resp.Body)
+	data, err := config.deps.ReadAllContext(ctx, resp.Body)
 	if err != nil {
 		return result, err
 	}
@@ -66,7 +66,7 @@ func download(ctx context.Context, config downloadConfig) (downloadResult, error
 	// turns out that Neubot and MK do the same. So, we do what they do. At
 	// the same time, we are currently not able to include the overhead that
 	// is caused by HTTP headers etc. So, we're a bit less precise.
-	result.elapsed = time.Now().Sub(savedTicks).Seconds()
+	result.elapsed = time.Since(savedTicks).Seconds()
 	result.received = int64(len(data))
 	result.requestTicks = savedTicks.Sub(config.begin).Seconds()
 	result.timestamp = time.Now().Unix()
diff --git a/internal/engine/experiment/dash/fake_test.go b/internal/engine/experiment/dash/fake_test.go
index baa9b5c..7f35618 100644
--- a/internal/engine/experiment/dash/fake_test.go
+++ b/internal/engine/experiment/dash/fake_test.go
@@ -1,6 +1,7 @@
 package dash
 
 import (
+	"context"
 	"io"
 	"net/http"
 	"time"
@@ -36,7 +37,7 @@ func (d FakeDeps) NewHTTPRequest(
 	return d.newHTTPRequestResult, d.newHTTPRequestErr
 }
 
-func (d FakeDeps) ReadAll(r io.Reader) ([]byte, error) {
+func (d FakeDeps) ReadAllContext(ctx context.Context, r io.Reader) ([]byte, error) {
 	return d.readAllResult, d.readAllErr
 }
 
diff --git a/internal/engine/experiment/dash/negotiate.go b/internal/engine/experiment/dash/negotiate.go
index 71968c4..1464099 100644
--- a/internal/engine/experiment/dash/negotiate.go
+++ b/internal/engine/experiment/dash/negotiate.go
@@ -16,7 +16,7 @@ type negotiateDeps interface {
 	JSONMarshal(v interface{}) ([]byte, error)
 	Logger() model.Logger
 	NewHTTPRequest(method string, url string, body io.Reader) (*http.Request, error)
-	ReadAll(r io.Reader) ([]byte, error)
+	ReadAllContext(ctx context.Context, r io.Reader) ([]byte, error)
 	Scheme() string
 	UserAgent() string
 }
@@ -48,7 +48,7 @@ func negotiate(
 		return negotiateResp, errHTTPRequestFailed
 	}
 	defer resp.Body.Close()
-	data, err = deps.ReadAll(resp.Body)
+	data, err = deps.ReadAllContext(ctx, resp.Body)
 	if err != nil {
 		return negotiateResp, err
 	}
diff --git a/internal/engine/experiment/dash/spec.go b/internal/engine/experiment/dash/spec.go
index b689b69..6b3060e 100644
--- a/internal/engine/experiment/dash/spec.go
+++ b/internal/engine/experiment/dash/spec.go
@@ -1,12 +1,6 @@
 package dash
 
 const (
-	// currentServerSchemaVersion is the version of the server schema that
-	// will be adopted by this implementation. Version 3 is the one that is
-	// Neubot uses. We needed to bump the version because Web100 is not on
-	// M-Lab anymore and hence we need to make a breaking change.
-	currentServerSchemaVersion = 4
-
 	// negotiatePath is the URL path used to negotiate
 	negotiatePath = "/negotiate/dash"
 
diff --git a/internal/engine/experiment/hhfm/fake_test.go b/internal/engine/experiment/hhfm/fake_test.go
index 3138c97..ee0c7b8 100644
--- a/internal/engine/experiment/hhfm/fake_test.go
+++ b/internal/engine/experiment/hhfm/fake_test.go
@@ -2,10 +2,11 @@ package hhfm_test
 
 import (
 	"context"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeDialer struct {
@@ -30,7 +31,7 @@ func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return txp.Func(req)
 	}
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/engine/experiment/hhfm/hhfm.go b/internal/engine/experiment/hhfm/hhfm.go
index a2eee07..d6b69e0 100644
--- a/internal/engine/experiment/hhfm/hhfm.go
+++ b/internal/engine/experiment/hhfm/hhfm.go
@@ -9,7 +9,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"sort"
@@ -21,6 +20,7 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/archival"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/dialer"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/errorx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/randx"
 )
 
@@ -198,7 +198,7 @@ func transact(txp Transport, req *http.Request,
 		return nil, nil, urlgetter.ErrHTTPRequestFailed
 	}
 	callbacks.OnProgress(0.75, "reading response body...")
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(req.Context(), resp.Body)
 	callbacks.OnProgress(1.00, fmt.Sprintf("got reseponse body... %+v", err))
 	if err != nil {
 		return nil, nil, err
diff --git a/internal/engine/experiment/ndt7/download.go b/internal/engine/experiment/ndt7/download.go
index 5adc0bb..447cde2 100644
--- a/internal/engine/experiment/ndt7/download.go
+++ b/internal/engine/experiment/ndt7/download.go
@@ -2,11 +2,12 @@ package ndt7
 
 import (
 	"context"
+	"errors"
 	"io"
-	"io/ioutil"
 	"time"
 
 	"github.com/gorilla/websocket"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type downloadManager struct {
@@ -33,6 +34,30 @@ func newDownloadManager(
 }
 
 func (mgr downloadManager) run(ctx context.Context) error {
+	return mgr.reduceErr(mgr.doRun(ctx))
+}
+
+// reduceErr treats as non-errors the errors caused by the context
+// so that we can focus instead on network errors.
+//
+// This function was introduced by https://github.com/ooni/probe-cli/pull/379
+// since before such a PR we did not see context interrupting
+// errors when we were reading messages. Since before such a PR
+// we used to return `nil` on context errors, this function is
+// here to keep the previous behavior by filtering the error
+// returned when reading messages, given that now reading messages
+// can fail midway because we use iox.ReadAllContext.
+func (mgr downloadManager) reduceErr(err error) error {
+	if errors.Is(err, context.Canceled) {
+		return nil
+	}
+	if errors.Is(err, context.DeadlineExceeded) {
+		return nil
+	}
+	return err
+}
+
+func (mgr downloadManager) doRun(ctx context.Context) error {
 	var total int64
 	start := time.Now()
 	if err := mgr.conn.SetReadDeadline(start.Add(mgr.maxRuntime)); err != nil {
@@ -47,7 +72,7 @@ func (mgr downloadManager) run(ctx context.Context) error {
 			return err
 		}
 		if kind == websocket.TextMessage {
-			data, err := ioutil.ReadAll(reader)
+			data, err := iox.ReadAllContext(ctx, reader)
 			if err != nil {
 				return err
 			}
@@ -57,7 +82,7 @@ func (mgr downloadManager) run(ctx context.Context) error {
 			}
 			continue
 		}
-		n, err := io.Copy(ioutil.Discard, reader)
+		n, err := io.Copy(io.Discard, reader)
 		if err != nil {
 			return err
 		}
diff --git a/internal/engine/experiment/ndt7/download_test.go b/internal/engine/experiment/ndt7/download_test.go
index bc393a3..fb3b1ed 100644
--- a/internal/engine/experiment/ndt7/download_test.go
+++ b/internal/engine/experiment/ndt7/download_test.go
@@ -143,3 +143,20 @@ type goodJSONReader struct{}
 func (r *goodJSONReader) Read(p []byte) (int, error) {
 	return copy(p, []byte(`{}`)), io.EOF
 }
+
+func TestDownloadReduceErr(t *testing.T) {
+	mgr := downloadManager{}
+	if mgr.reduceErr(context.Canceled) != nil {
+		t.Fatal("reduceErr not working as intended for context.Canceled")
+	}
+	if mgr.reduceErr(context.DeadlineExceeded) != nil {
+		t.Fatal("reduceErr not working as intended for context.DeadlineExceeded")
+	}
+	if mgr.reduceErr(nil) != nil {
+		t.Fatal("reduceErr not working as intended for nil")
+	}
+	expected := errors.New("mocked error")
+	if mgr.reduceErr(expected) != expected {
+		t.Fatal("reduceErr not working as intended for other errors")
+	}
+}
diff --git a/internal/engine/geolocate/fake_test.go b/internal/engine/geolocate/fake_test.go
index 93978c5..93c8589 100644
--- a/internal/engine/geolocate/fake_test.go
+++ b/internal/engine/geolocate/fake_test.go
@@ -1,9 +1,10 @@
 package geolocate
 
 import (
-	"io/ioutil"
 	"net/http"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeTransport struct {
@@ -14,7 +15,7 @@ type FakeTransport struct {
 func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 	time.Sleep(10 * time.Microsecond)
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/engine/httpx/fake_test.go b/internal/engine/httpx/fake_test.go
index 2ae6cfd..a5c94ea 100644
--- a/internal/engine/httpx/fake_test.go
+++ b/internal/engine/httpx/fake_test.go
@@ -1,9 +1,10 @@
 package httpx
 
 import (
-	"io/ioutil"
 	"net/http"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeTransport struct {
@@ -18,7 +19,7 @@ func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return txp.Func(req)
 	}
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/engine/httpx/jsonapi.go b/internal/engine/httpx/jsonapi.go
index 1d4dcae..0845295 100644
--- a/internal/engine/httpx/jsonapi.go
+++ b/internal/engine/httpx/jsonapi.go
@@ -7,9 +7,10 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 // Logger is the definition of Logger used by this package.
@@ -100,7 +101,7 @@ func (c Client) Do(request *http.Request) ([]byte, error) {
 	if response.StatusCode >= 400 {
 		return nil, fmt.Errorf("httpx: request failed: %s", response.Status)
 	}
-	return ioutil.ReadAll(response.Body)
+	return iox.ReadAllContext(request.Context(), response.Body)
 }
 
 // DoJSON performs the provided request and unmarshals the JSON response body
diff --git a/internal/engine/internal/mlablocate/mlablocate.go b/internal/engine/internal/mlablocate/mlablocate.go
index c8591c6..6574ae7 100644
--- a/internal/engine/internal/mlablocate/mlablocate.go
+++ b/internal/engine/internal/mlablocate/mlablocate.go
@@ -6,11 +6,11 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/model"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 // Client is a locate.measurementlab.net client.
@@ -63,7 +63,7 @@ func (c *Client) Query(ctx context.Context, tool string) (Result, error) {
 	if resp.StatusCode != 200 {
 		return Result{}, fmt.Errorf("mlablocate: non-200 status code: %d", resp.StatusCode)
 	}
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(ctx, resp.Body)
 	if err != nil {
 		return Result{}, err
 	}
diff --git a/internal/engine/internal/mlablocatev2/fake_test.go b/internal/engine/internal/mlablocatev2/fake_test.go
index 0fc63ac..c0228d8 100644
--- a/internal/engine/internal/mlablocatev2/fake_test.go
+++ b/internal/engine/internal/mlablocatev2/fake_test.go
@@ -1,9 +1,10 @@
 package mlablocatev2
 
 import (
-	"io/ioutil"
 	"net/http"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeTransport struct {
@@ -18,7 +19,7 @@ func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return txp.Func(req)
 	}
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/engine/internal/mlablocatev2/mlablocatev2.go b/internal/engine/internal/mlablocatev2/mlablocatev2.go
index cda8cf2..36777d3 100644
--- a/internal/engine/internal/mlablocatev2/mlablocatev2.go
+++ b/internal/engine/internal/mlablocatev2/mlablocatev2.go
@@ -6,12 +6,12 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"regexp"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/model"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 const (
@@ -102,7 +102,7 @@ func (c Client) query(ctx context.Context, path string) (resultRecord, error) {
 	if resp.StatusCode != 200 {
 		return resultRecord{}, fmt.Errorf("%w: %d", ErrRequestFailed, resp.StatusCode)
 	}
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(ctx, resp.Body)
 	if err != nil {
 		return resultRecord{}, err
 	}
diff --git a/internal/engine/legacy/netx/dialer.go b/internal/engine/legacy/netx/dialer.go
index 56721f0..ec3ff93 100644
--- a/internal/engine/legacy/netx/dialer.go
+++ b/internal/engine/legacy/netx/dialer.go
@@ -135,7 +135,7 @@ func (d *Dialer) SetCABundle(path string) error {
 		return err
 	}
 	pool := x509.NewCertPool()
-	if pool.AppendCertsFromPEM(cert) == false {
+	if !pool.AppendCertsFromPEM(cert) {
 		return errors.New("AppendCertsFromPEM failed")
 	}
 	d.TLSConfig.RootCAs = pool
diff --git a/internal/engine/legacy/netx/http_test.go b/internal/engine/legacy/netx/http_test.go
index 4e8551c..52794ca 100644
--- a/internal/engine/legacy/netx/http_test.go
+++ b/internal/engine/legacy/netx/http_test.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"crypto/x509"
 	"errors"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/http/httptest"
@@ -15,6 +14,7 @@ import (
 
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/errorx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func dowithclient(t *testing.T, client *netx.HTTPClient) {
@@ -24,7 +24,7 @@ func dowithclient(t *testing.T, client *netx.HTTPClient) {
 		t.Fatal(err)
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -126,7 +126,7 @@ func httpProxyTestMain(t *testing.T, client *http.Client, expect int) {
 		t.Fatal(err)
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/legacy/netx/oldhttptransport/bodytracer.go b/internal/engine/legacy/netx/oldhttptransport/bodytracer.go
index ed46c64..8d39628 100644
--- a/internal/engine/legacy/netx/oldhttptransport/bodytracer.go
+++ b/internal/engine/legacy/netx/oldhttptransport/bodytracer.go
@@ -63,7 +63,7 @@ func (bw *bodyWrapper) Read(b []byte) (n int, err error) {
 			// bytes read (0 <= n <= len(p)) and any error encountered."
 			Data:                   b[:n],
 			Error:                  err,
-			DurationSinceBeginning: time.Now().Sub(bw.root.Beginning),
+			DurationSinceBeginning: time.Since(bw.root.Beginning),
 			TransactionID:          bw.tid,
 		},
 	})
@@ -74,7 +74,7 @@ func (bw *bodyWrapper) Close() (err error) {
 	err = bw.ReadCloser.Close()
 	bw.root.Handler.OnMeasurement(modelx.Measurement{
 		HTTPResponseDone: &modelx.HTTPResponseDoneEvent{
-			DurationSinceBeginning: time.Now().Sub(bw.root.Beginning),
+			DurationSinceBeginning: time.Since(bw.root.Beginning),
 			TransactionID:          bw.tid,
 		},
 	})
diff --git a/internal/engine/legacy/netx/oldhttptransport/bodytracer_test.go b/internal/engine/legacy/netx/oldhttptransport/bodytracer_test.go
index 8d8e2c0..a33d71b 100644
--- a/internal/engine/legacy/netx/oldhttptransport/bodytracer_test.go
+++ b/internal/engine/legacy/netx/oldhttptransport/bodytracer_test.go
@@ -1,9 +1,11 @@
 package oldhttptransport
 
 import (
-	"io/ioutil"
+	"context"
 	"net/http"
 	"testing"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestBodyTracerSuccess(t *testing.T) {
@@ -15,7 +17,7 @@ func TestBodyTracerSuccess(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/legacy/netx/oldhttptransport/httptransport_test.go b/internal/engine/legacy/netx/oldhttptransport/httptransport_test.go
index b1c06ae..835dc3d 100644
--- a/internal/engine/legacy/netx/oldhttptransport/httptransport_test.go
+++ b/internal/engine/legacy/netx/oldhttptransport/httptransport_test.go
@@ -1,9 +1,11 @@
 package oldhttptransport
 
 import (
-	"io/ioutil"
+	"context"
 	"net/http"
 	"testing"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestGood(t *testing.T) {
@@ -15,7 +17,7 @@ func TestGood(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/legacy/netx/oldhttptransport/tracetripper.go b/internal/engine/legacy/netx/oldhttptransport/tracetripper.go
index baad6dd..ff88aa6 100644
--- a/internal/engine/legacy/netx/oldhttptransport/tracetripper.go
+++ b/internal/engine/legacy/netx/oldhttptransport/tracetripper.go
@@ -2,9 +2,9 @@ package oldhttptransport
 
 import (
 	"bytes"
+	"context"
 	"crypto/tls"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptrace"
 	"sync"
@@ -16,21 +16,22 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx/modelx"
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx/transactionid"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/errorx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 // TraceTripper performs single HTTP transactions.
 type TraceTripper struct {
-	readAllErrs  *atomicx.Int64
-	readAll      func(r io.Reader) ([]byte, error)
-	roundTripper http.RoundTripper
+	readAllErrs    *atomicx.Int64
+	readAllContext func(ctx context.Context, r io.Reader) ([]byte, error)
+	roundTripper   http.RoundTripper
 }
 
 // NewTraceTripper creates a new Transport.
 func NewTraceTripper(roundTripper http.RoundTripper) *TraceTripper {
 	return &TraceTripper{
-		readAllErrs:  &atomicx.Int64{},
-		readAll:      ioutil.ReadAll,
-		roundTripper: roundTripper,
+		readAllErrs:    &atomicx.Int64{},
+		readAllContext: iox.ReadAllContext,
+		roundTripper:   roundTripper,
 	}
 }
 
@@ -57,10 +58,10 @@ func (c *readCloseWrapper) Close() error {
 }
 
 func readSnap(
-	source *io.ReadCloser, limit int64,
-	readAll func(r io.Reader) ([]byte, error),
+	ctx context.Context, source *io.ReadCloser, limit int64,
+	readAllContext func(ctx context.Context, r io.Reader) ([]byte, error),
 ) (data []byte, err error) {
-	data, err = readAll(io.LimitReader(*source, limit))
+	data, err = readAllContext(ctx, io.LimitReader(*source, limit))
 	if err == nil {
 		*source = newReadCloseWrapper(
 			io.MultiReader(bytes.NewReader(data), *source),
@@ -79,7 +80,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 	root.Handler.OnMeasurement(modelx.Measurement{
 		HTTPRoundTripStart: &modelx.HTTPRoundTripStartEvent{
 			DialID:                 dialid.ContextDialID(req.Context()),
-			DurationSinceBeginning: time.Now().Sub(root.Beginning),
+			DurationSinceBeginning: time.Since(root.Beginning),
 			Method:                 req.Method,
 			TransactionID:          tid,
 			URL:                    req.URL.String(),
@@ -98,7 +99,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 
 	// Save a snapshot of the request body
 	if req.Body != nil {
-		requestBody, err = readSnap(&req.Body, snapSize, t.readAll)
+		requestBody, err = readSnap(req.Context(), &req.Body, snapSize, t.readAllContext)
 		if err != nil {
 			return nil, err
 		}
@@ -114,7 +115,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 			// configured in the http.Transport
 			root.Handler.OnMeasurement(modelx.Measurement{
 				TLSHandshakeStart: &modelx.TLSHandshakeStartEvent{
-					DurationSinceBeginning: time.Now().Sub(root.Beginning),
+					DurationSinceBeginning: time.Since(root.Beginning),
 					TransactionID:          tid,
 				},
 			})
@@ -127,7 +128,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 				Operation:     errorx.TLSHandshakeOperation,
 				TransactionID: tid,
 			}.MaybeBuild()
-			durationSinceBeginning := time.Now().Sub(root.Beginning)
+			durationSinceBeginning := time.Since(root.Beginning)
 			// Event emitted by net/http when DialTLS is not
 			// configured in the http.Transport
 			root.Handler.OnMeasurement(modelx.Measurement{
@@ -149,7 +150,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 						info.Conn.LocalAddr().Network(),
 						info.Conn.LocalAddr().String(),
 					),
-					DurationSinceBeginning: time.Now().Sub(root.Beginning),
+					DurationSinceBeginning: time.Since(root.Beginning),
 					TransactionID:          tid,
 				},
 			})
@@ -165,7 +166,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 			requestHeadersMu.Unlock()
 			root.Handler.OnMeasurement(modelx.Measurement{
 				HTTPRequestHeader: &modelx.HTTPRequestHeaderEvent{
-					DurationSinceBeginning: time.Now().Sub(root.Beginning),
+					DurationSinceBeginning: time.Since(root.Beginning),
 					Key:                    key,
 					TransactionID:          tid,
 					Value:                  values,
@@ -175,7 +176,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 		WroteHeaders: func() {
 			root.Handler.OnMeasurement(modelx.Measurement{
 				HTTPRequestHeadersDone: &modelx.HTTPRequestHeadersDoneEvent{
-					DurationSinceBeginning: time.Now().Sub(root.Beginning),
+					DurationSinceBeginning: time.Since(root.Beginning),
 					Headers:                requestHeaders, // [*]
 					Method:                 req.Method,     // [*]
 					TransactionID:          tid,
@@ -193,7 +194,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 			}.MaybeBuild()
 			root.Handler.OnMeasurement(modelx.Measurement{
 				HTTPRequestDone: &modelx.HTTPRequestDoneEvent{
-					DurationSinceBeginning: time.Now().Sub(root.Beginning),
+					DurationSinceBeginning: time.Since(root.Beginning),
 					Error:                  err,
 					TransactionID:          tid,
 				},
@@ -202,7 +203,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 		GotFirstResponseByte: func() {
 			root.Handler.OnMeasurement(modelx.Measurement{
 				HTTPResponseStart: &modelx.HTTPResponseStartEvent{
-					DurationSinceBeginning: time.Now().Sub(root.Beginning),
+					DurationSinceBeginning: time.Since(root.Beginning),
 					TransactionID:          tid,
 				},
 			})
@@ -233,7 +234,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 	// [*] Require less event joining work by providing info that
 	// makes this event alone actionable for OONI
 	event := &modelx.HTTPRoundTripDoneEvent{
-		DurationSinceBeginning: time.Now().Sub(root.Beginning),
+		DurationSinceBeginning: time.Since(root.Beginning),
 		Error:                  err,
 		RequestBodySnap:        requestBody,
 		RequestHeaders:         requestHeaders,   // [*]
@@ -248,7 +249,7 @@ func (t *TraceTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 		event.ResponseProto = resp.Proto
 		// Save a snapshot of the response body
 		var data []byte
-		data, err = readSnap(&resp.Body, snapSize, t.readAll)
+		data, err = readSnap(req.Context(), &resp.Body, snapSize, t.readAllContext)
 		if err != nil {
 			t.readAllErrs.Add(1)
 			resp = nil // this is how net/http likes it
diff --git a/internal/engine/legacy/netx/oldhttptransport/tracetripper_test.go b/internal/engine/legacy/netx/oldhttptransport/tracetripper_test.go
index f53e4ab..990bc4a 100644
--- a/internal/engine/legacy/netx/oldhttptransport/tracetripper_test.go
+++ b/internal/engine/legacy/netx/oldhttptransport/tracetripper_test.go
@@ -5,7 +5,6 @@ import (
 	"context"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptrace"
 	"sync"
@@ -14,6 +13,7 @@ import (
 
 	"github.com/miekg/dns"
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx/modelx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestTraceTripperSuccess(t *testing.T) {
@@ -25,7 +25,7 @@ func TestTraceTripperSuccess(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -47,7 +47,7 @@ func (h *roundTripHandler) OnMeasurement(m modelx.Measurement) {
 
 func TestTraceTripperReadAllFailure(t *testing.T) {
 	transport := NewTraceTripper(http.DefaultTransport)
-	transport.readAll = func(r io.Reader) ([]byte, error) {
+	transport.readAllContext = func(ctx context.Context, r io.Reader) ([]byte, error) {
 		return nil, io.EOF
 	}
 	client := &http.Client{Transport: transport}
@@ -156,7 +156,7 @@ func TestTraceTripperWithCorrectSnaps(t *testing.T) {
 
 	// Read the whole response body, parse it as valid DNS
 	// reply and verify we obtained what we expected
-	replyData, err := ioutil.ReadAll(resp.Body)
+	replyData, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -230,7 +230,7 @@ func TestTraceTripperWithReadAllFailingForBody(t *testing.T) {
 	// use such transport to configure an ordinary client
 	transport := NewTraceTripper(http.DefaultTransport)
 	errorMocked := errors.New("mocked error")
-	transport.readAll = func(r io.Reader) ([]byte, error) {
+	transport.readAllContext = func(ctx context.Context, r io.Reader) ([]byte, error) {
 		return nil, errorMocked
 	}
 	const snapSize = 15
diff --git a/internal/engine/legacy/netx/oldhttptransport/transactioner_test.go b/internal/engine/legacy/netx/oldhttptransport/transactioner_test.go
index 1eb9cc0..d7804fe 100644
--- a/internal/engine/legacy/netx/oldhttptransport/transactioner_test.go
+++ b/internal/engine/legacy/netx/oldhttptransport/transactioner_test.go
@@ -1,11 +1,12 @@
 package oldhttptransport
 
 import (
-	"io/ioutil"
+	"context"
 	"net/http"
 	"testing"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx/transactionid"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type transactionerCheckTransactionID struct {
@@ -33,7 +34,7 @@ func TestTransactionerSuccess(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/legacy/netxlogger/netxlogger_test.go b/internal/engine/legacy/netxlogger/netxlogger_test.go
index 00dd38b..3bf64ba 100644
--- a/internal/engine/legacy/netxlogger/netxlogger_test.go
+++ b/internal/engine/legacy/netxlogger/netxlogger_test.go
@@ -1,7 +1,7 @@
 package netxlogger
 
 import (
-	"io/ioutil"
+	"context"
 	"net/http"
 	"testing"
 	"time"
@@ -10,6 +10,7 @@ import (
 	"github.com/apex/log/handlers/discard"
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx"
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx/modelx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestGood(t *testing.T) {
@@ -32,7 +33,7 @@ func TestGood(t *testing.T) {
 		t.Fatal("expected non-nil resp here")
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/legacy/oonitemplates/oonitemplates.go b/internal/engine/legacy/oonitemplates/oonitemplates.go
index cb7ba09..3be2291 100644
--- a/internal/engine/legacy/oonitemplates/oonitemplates.go
+++ b/internal/engine/legacy/oonitemplates/oonitemplates.go
@@ -24,6 +24,7 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx"
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx/handlers"
 	"github.com/ooni/probe-cli/v3/internal/engine/legacy/netx/modelx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/runtimex"
 	"gitlab.com/yawning/obfs4.git/transports"
 	obfs4base "gitlab.com/yawning/obfs4.git/transports/base"
@@ -90,7 +91,7 @@ func (m *connmapper) scramble(cid int64) int64 {
 	// See https://stackoverflow.com/a/38140573/4354461
 	m.mu.Lock()
 	defer m.mu.Unlock()
-	if value, found := m.table[cid]; found == true {
+	if value, found := m.table[cid]; found {
 		return value
 	}
 	var factor int64 = 1
@@ -366,7 +367,7 @@ func HTTPDo(
 				config.MaxResponseBodySnapSize,
 			),
 		)
-		data, err := ioutil.ReadAll(reader)
+		data, err := iox.ReadAllContext(ctx, reader)
 		mu.Lock()
 		results.BodySnap, results.Error = data, err
 		mu.Unlock()
diff --git a/internal/engine/legacy/oonitemplates/oonitemplates_test.go b/internal/engine/legacy/oonitemplates/oonitemplates_test.go
index 683ab96..ae78760 100644
--- a/internal/engine/legacy/oonitemplates/oonitemplates_test.go
+++ b/internal/engine/legacy/oonitemplates/oonitemplates_test.go
@@ -377,7 +377,7 @@ type faketransport struct {
 }
 
 func (txp *faketransport) Name() string {
-	return txp.Name()
+	return txp.txp.Name()
 }
 
 func (txp *faketransport) ClientFactory(stateDir string) (obfs4base.ClientFactory, error) {
@@ -385,7 +385,7 @@ func (txp *faketransport) ClientFactory(stateDir string) (obfs4base.ClientFactor
 }
 
 func (txp *faketransport) ServerFactory(stateDir string, args *goptlib.Args) (obfs4base.ServerFactory, error) {
-	return txp.ServerFactory(stateDir, args)
+	return txp.txp.ServerFactory(stateDir, args)
 }
 
 func TestConnmapper(t *testing.T) {
diff --git a/internal/engine/netx/fake_test.go b/internal/engine/netx/fake_test.go
index 2c3b464..ba3f816 100644
--- a/internal/engine/netx/fake_test.go
+++ b/internal/engine/netx/fake_test.go
@@ -2,10 +2,11 @@ package netx
 
 import (
 	"context"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeDialer struct {
@@ -30,7 +31,7 @@ func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return txp.Func(req)
 	}
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/engine/netx/httptransport/bytecounter_test.go b/internal/engine/netx/httptransport/bytecounter_test.go
index dd5005f..a4a7713 100644
--- a/internal/engine/netx/httptransport/bytecounter_test.go
+++ b/internal/engine/netx/httptransport/bytecounter_test.go
@@ -1,6 +1,7 @@
 package httptransport_test
 
 import (
+	"context"
 	"errors"
 	"io"
 	"io/ioutil"
@@ -10,6 +11,7 @@ import (
 
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/bytecounter"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/httptransport"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestByteCounterFailure(t *testing.T) {
@@ -68,7 +70,7 @@ func TestByteCounterSuccess(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -104,7 +106,7 @@ func TestByteCounterSuccessWithEOF(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/netx/httptransport/fake_test.go b/internal/engine/netx/httptransport/fake_test.go
index 4f2a25b..e5bbb0f 100644
--- a/internal/engine/netx/httptransport/fake_test.go
+++ b/internal/engine/netx/httptransport/fake_test.go
@@ -2,10 +2,11 @@ package httptransport
 
 import (
 	"context"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeDialer struct {
@@ -30,7 +31,7 @@ func (txp FakeTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return txp.Func(req)
 	}
 	if req.Body != nil {
-		ioutil.ReadAll(req.Body)
+		iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if txp.Err != nil {
diff --git a/internal/engine/netx/httptransport/logging_test.go b/internal/engine/netx/httptransport/logging_test.go
index c9c8a16..ae632f5 100644
--- a/internal/engine/netx/httptransport/logging_test.go
+++ b/internal/engine/netx/httptransport/logging_test.go
@@ -1,6 +1,7 @@
 package httptransport_test
 
 import (
+	"context"
 	"errors"
 	"io"
 	"io/ioutil"
@@ -11,6 +12,7 @@ import (
 
 	"github.com/apex/log"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/httptransport"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestLoggingFailure(t *testing.T) {
@@ -72,6 +74,6 @@ func TestLoggingSuccess(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	ioutil.ReadAll(resp.Body)
+	iox.ReadAllContext(context.Background(), resp.Body)
 	resp.Body.Close()
 }
diff --git a/internal/engine/netx/httptransport/saver.go b/internal/engine/netx/httptransport/saver.go
index f75bfdb..c94d4df 100644
--- a/internal/engine/netx/httptransport/saver.go
+++ b/internal/engine/netx/httptransport/saver.go
@@ -2,14 +2,15 @@ package httptransport
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptrace"
 	"time"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/trace"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 // SaverPerformanceHTTPTransport is a RoundTripper that saves
@@ -109,7 +110,7 @@ func (txp SaverBodyHTTPTransport) RoundTrip(req *http.Request) (*http.Response,
 		snapsize = txp.SnapshotSize
 	}
 	if req.Body != nil {
-		data, err := saverSnapRead(req.Body, snapsize)
+		data, err := saverSnapRead(req.Context(), req.Body, snapsize)
 		if err != nil {
 			return nil, err
 		}
@@ -125,7 +126,7 @@ func (txp SaverBodyHTTPTransport) RoundTrip(req *http.Request) (*http.Response,
 	if err != nil {
 		return nil, err
 	}
-	data, err := saverSnapRead(resp.Body, snapsize)
+	data, err := saverSnapRead(req.Context(), resp.Body, snapsize)
 	err = ignoreExpectedEOF(err, resp)
 	if err != nil {
 		resp.Body.Close()
@@ -157,8 +158,8 @@ func ignoreExpectedEOF(err error, resp *http.Response) error {
 	return err
 }
 
-func saverSnapRead(r io.ReadCloser, snapsize int) ([]byte, error) {
-	return ioutil.ReadAll(io.LimitReader(r, int64(snapsize)))
+func saverSnapRead(ctx context.Context, r io.ReadCloser, snapsize int) ([]byte, error) {
+	return iox.ReadAllContext(ctx, io.LimitReader(r, int64(snapsize)))
 }
 
 func saverCompose(data []byte, r io.ReadCloser) io.ReadCloser {
diff --git a/internal/engine/netx/httptransport/saver_test.go b/internal/engine/netx/httptransport/saver_test.go
index 8846107..fd484a0 100644
--- a/internal/engine/netx/httptransport/saver_test.go
+++ b/internal/engine/netx/httptransport/saver_test.go
@@ -1,6 +1,7 @@
 package httptransport_test
 
 import (
+	"context"
 	"errors"
 	"io/ioutil"
 	"net/http"
@@ -10,6 +11,7 @@ import (
 
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/httptransport"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/trace"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestSaverPerformanceNoMultipleEvents(t *testing.T) {
@@ -245,7 +247,7 @@ func TestSaverBodySuccess(t *testing.T) {
 	txp := httptransport.SaverBodyHTTPTransport{
 		RoundTripper: httptransport.FakeTransport{
 			Func: func(req *http.Request) (*http.Response, error) {
-				data, err := ioutil.ReadAll(req.Body)
+				data, err := iox.ReadAllContext(context.Background(), req.Body)
 				if err != nil {
 					t.Fatal(err)
 				}
@@ -274,7 +276,7 @@ func TestSaverBodySuccess(t *testing.T) {
 		t.Fatal("unexpected status code")
 	}
 	defer resp.Body.Close()
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/netx/integration_test.go b/internal/engine/netx/integration_test.go
index 0b7db6d..9f3bb37 100644
--- a/internal/engine/netx/integration_test.go
+++ b/internal/engine/netx/integration_test.go
@@ -3,7 +3,6 @@ package netx_test
 import (
 	"context"
 	"errors"
-	"io/ioutil"
 	"net/http"
 	"testing"
 
@@ -12,6 +11,7 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/bytecounter"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/errorx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/trace"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestSuccess(t *testing.T) {
@@ -38,7 +38,7 @@ func TestSuccess(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if _, err = ioutil.ReadAll(resp.Body); err != nil {
+	if _, err = iox.ReadAllContext(context.Background(), resp.Body); err != nil {
 		t.Fatal(err)
 	}
 	if err = resp.Body.Close(); err != nil {
diff --git a/internal/engine/netx/resolver/dnsoverhttps.go b/internal/engine/netx/resolver/dnsoverhttps.go
index 8041024..e0686b1 100644
--- a/internal/engine/netx/resolver/dnsoverhttps.go
+++ b/internal/engine/netx/resolver/dnsoverhttps.go
@@ -4,11 +4,11 @@ import (
 	"bytes"
 	"context"
 	"errors"
-	"io/ioutil"
 	"net/http"
 	"time"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/httpheader"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 // DNSOverHTTPS is a DNS over HTTPS RoundTripper. Requests are submitted over
@@ -56,7 +56,7 @@ func (t DNSOverHTTPS) RoundTrip(ctx context.Context, query []byte) ([]byte, erro
 	if resp.Header.Get("content-type") != "application/dns-message" {
 		return nil, errors.New("doh: invalid content-type")
 	}
-	return ioutil.ReadAll(resp.Body)
+	return iox.ReadAllContext(ctx, resp.Body)
 }
 
 // RequiresPadding returns true for DoH according to RFC8467
diff --git a/internal/engine/netx/tlsx/certifi.go b/internal/engine/netx/tlsx/certifi.go
index 23b4ed7..1af3da1 100644
--- a/internal/engine/netx/tlsx/certifi.go
+++ b/internal/engine/netx/tlsx/certifi.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-06-08 14:36:18.474117 +0200 CEST m=+0.459588210
+// 2021-06-15 10:55:55.638897 +0200 CEST m=+4.257631084
 // https://curl.haxx.se/ca/cacert.pem
 
 package tlsx
diff --git a/internal/engine/netx/tlsx/generate.go b/internal/engine/netx/tlsx/generate.go
index b9ae011..154b93e 100644
--- a/internal/engine/netx/tlsx/generate.go
+++ b/internal/engine/netx/tlsx/generate.go
@@ -12,14 +12,16 @@
 package main
 
 import (
+	"context"
 	"crypto/x509"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
 	"strings"
 	"text/template"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 var tmpl = template.Must(template.New("").Parse(`// Code generated by go generate; DO NOT EDIT.
@@ -50,7 +52,7 @@ func main() {
 	}
 	defer resp.Body.Close()
 
-	bundle, err := ioutil.ReadAll(resp.Body)
+	bundle, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/internal/engine/probeservices/collector_test.go b/internal/engine/probeservices/collector_test.go
index c95b6dd..ed0dceb 100644
--- a/internal/engine/probeservices/collector_test.go
+++ b/internal/engine/probeservices/collector_test.go
@@ -15,6 +15,7 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"github.com/ooni/probe-cli/v3/internal/engine/model"
 	"github.com/ooni/probe-cli/v3/internal/engine/probeservices"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type fakeTestKeys struct {
@@ -233,7 +234,7 @@ func TestEndToEnd(t *testing.T) {
 				return
 			}
 			if r.RequestURI == "/report/_id" {
-				data, err := ioutil.ReadAll(r.Body)
+				data, err := iox.ReadAllContext(r.Context(), r.Body)
 				if err != nil {
 					panic(err)
 				}
diff --git a/internal/engine/probeservices/probeservices_test.go b/internal/engine/probeservices/probeservices_test.go
index fdb9123..3ea93d3 100644
--- a/internal/engine/probeservices/probeservices_test.go
+++ b/internal/engine/probeservices/probeservices_test.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"regexp"
 	"strings"
@@ -17,6 +16,7 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine/model"
 	"github.com/ooni/probe-cli/v3/internal/engine/probeservices"
 	"github.com/ooni/probe-cli/v3/internal/engine/probeservices/testorchestra"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func newclient() *probeservices.Client {
@@ -165,7 +165,7 @@ func TestCloudfront(t *testing.T) {
 	if resp.StatusCode != 200 {
 		t.Fatal("unexpected status code")
 	}
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(req.Context(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/engine/session_psiphon.go b/internal/engine/session_psiphon.go
index a6ee33e..050e264 100644
--- a/internal/engine/session_psiphon.go
+++ b/internal/engine/session_psiphon.go
@@ -6,9 +6,9 @@ import (
 	"bytes"
 	"context"
 	_ "embed"
-	"io/ioutil"
 
 	"filippo.io/age"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 //go:embed psiphon-config.json.age
@@ -34,7 +34,7 @@ func (s *sessionTunnelEarlySession) FetchPsiphonConfig(ctx context.Context) ([]b
 	if err != nil {
 		return nil, err
 	}
-	return ioutil.ReadAll(output)
+	return iox.ReadAllContext(ctx, output)
 }
 
 // FetchPsiphonConfig decrypts psiphonConfigJSONAge using
diff --git a/internal/iox/example_test.go b/internal/iox/example_test.go
new file mode 100644
index 0000000..3c3abc4
--- /dev/null
+++ b/internal/iox/example_test.go
@@ -0,0 +1,21 @@
+package iox_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"strings"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
+)
+
+func ExampleReadAllContext() {
+	r := strings.NewReader("deadbeef")
+	ctx := context.Background()
+	out, err := iox.ReadAllContext(ctx, r)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("%d\n", len(out))
+	// Output: 8
+}
diff --git a/internal/iox/iox.go b/internal/iox/iox.go
new file mode 100644
index 0000000..f083d53
--- /dev/null
+++ b/internal/iox/iox.go
@@ -0,0 +1,47 @@
+// Package iox contains io extensions.
+package iox
+
+import (
+	"context"
+	"io"
+)
+
+// ReadAllContext reads the whole reader r in a
+// background goroutine. This function will return
+// earlier if the context is cancelled. In which case
+// we will continue reading from r in the background
+// goroutine, and we will discard the result. To stop
+// the long-running goroutine, you need to close the
+// connection bound to the r reader, if possible.
+func ReadAllContext(ctx context.Context, r io.Reader) ([]byte, error) {
+	datach, errch := make(chan []byte, 1), make(chan error, 1) // buffers
+	go func() {
+		data, err := io.ReadAll(r)
+		if err != nil {
+			errch <- err
+			return
+		}
+		datach <- data
+	}()
+	select {
+	case data := <-datach:
+		return data, nil
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	case err := <-errch:
+		return nil, err
+	}
+}
+
+// MockableReader allows to mock any io.Reader.
+type MockableReader struct {
+	MockRead func(b []byte) (int, error)
+}
+
+// MockableReader implements an io.Reader.
+var _ io.Reader = &MockableReader{}
+
+// Read implements io.Reader.Read.
+func (r *MockableReader) Read(b []byte) (int, error) {
+	return r.MockRead(b)
+}
diff --git a/internal/iox/iox_test.go b/internal/iox/iox_test.go
new file mode 100644
index 0000000..ccd2d0b
--- /dev/null
+++ b/internal/iox/iox_test.go
@@ -0,0 +1,70 @@
+package iox
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestReadAllContextCommonCase(t *testing.T) {
+	r := strings.NewReader("deadbeef")
+	ctx := context.Background()
+	out, err := ReadAllContext(ctx, r)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(out) != 8 {
+		t.Fatal("not the expected number of bytes")
+	}
+}
+
+func TestReadAllContextWithError(t *testing.T) {
+	expected := errors.New("mocked error")
+	r := &MockableReader{
+		MockRead: func(b []byte) (int, error) {
+			return 0, expected
+		},
+	}
+	ctx := context.Background()
+	out, err := ReadAllContext(ctx, r)
+	if !errors.Is(err, expected) {
+		t.Fatal("not the error we expected", err)
+	}
+	if len(out) != 0 {
+		t.Fatal("not the expected number of bytes")
+	}
+}
+
+func TestReadAllContextWithCancelledContext(t *testing.T) {
+	r := strings.NewReader("deadbeef")
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel() // fail immediately
+	out, err := ReadAllContext(ctx, r)
+	if !errors.Is(err, context.Canceled) {
+		t.Fatal("not the error we expected", err)
+	}
+	if len(out) != 0 {
+		t.Fatal("not the expected number of bytes")
+	}
+}
+
+func TestReadAllContextWithErrorAndCancelledContext(t *testing.T) {
+	expected := errors.New("mocked error")
+	r := &MockableReader{
+		MockRead: func(b []byte) (int, error) {
+			time.Sleep(time.Millisecond)
+			return 0, expected
+		},
+	}
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel() // fail immediately
+	out, err := ReadAllContext(ctx, r)
+	if !errors.Is(err, context.Canceled) {
+		t.Fatal("not the error we expected", err)
+	}
+	if len(out) != 0 {
+		t.Fatal("not the expected number of bytes")
+	}
+}
diff --git a/internal/ooapi/apis.go b/internal/ooapi/apis.go
index dfe60c9..bb76b32 100644
--- a/internal/ooapi/apis.go
+++ b/internal/ooapi/apis.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:00.422051399 +0200 CEST m=+0.000129449
+// 2021-06-15 10:55:55.967236 +0200 CEST m=+0.000374501
 
 package ooapi
 
@@ -59,7 +59,8 @@ func (api *simpleCheckReportIDAPI) Call(ctx context.Context, req *apimodel.Check
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleCheckInAPI implements the CheckIn API.
@@ -109,7 +110,8 @@ func (api *simpleCheckInAPI) Call(ctx context.Context, req *apimodel.CheckInRequ
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleLoginAPI implements the Login API.
@@ -159,7 +161,8 @@ func (api *simpleLoginAPI) Call(ctx context.Context, req *apimodel.LoginRequest)
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleMeasurementMetaAPI implements the MeasurementMeta API.
@@ -209,7 +212,8 @@ func (api *simpleMeasurementMetaAPI) Call(ctx context.Context, req *apimodel.Mea
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleRegisterAPI implements the Register API.
@@ -259,7 +263,8 @@ func (api *simpleRegisterAPI) Call(ctx context.Context, req *apimodel.RegisterRe
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleTestHelpersAPI implements the TestHelpers API.
@@ -309,7 +314,8 @@ func (api *simpleTestHelpersAPI) Call(ctx context.Context, req *apimodel.TestHel
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simplePsiphonConfigAPI implements the PsiphonConfig API.
@@ -377,7 +383,8 @@ func (api *simplePsiphonConfigAPI) Call(ctx context.Context, req *apimodel.Psiph
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleTorTargetsAPI implements the TorTargets API.
@@ -445,7 +452,8 @@ func (api *simpleTorTargetsAPI) Call(ctx context.Context, req *apimodel.TorTarge
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleURLsAPI implements the URLs API.
@@ -495,7 +503,8 @@ func (api *simpleURLsAPI) Call(ctx context.Context, req *apimodel.URLsRequest) (
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleOpenReportAPI implements the OpenReport API.
@@ -545,7 +554,8 @@ func (api *simpleOpenReportAPI) Call(ctx context.Context, req *apimodel.OpenRepo
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
 
 // simpleSubmitMeasurementAPI implements the SubmitMeasurement API.
@@ -603,5 +613,6 @@ func (api *simpleSubmitMeasurementAPI) Call(ctx context.Context, req *apimodel.S
 	if api.UserAgent != "" {
 		httpReq.Header.Add("User-Agent", api.UserAgent)
 	}
-	return api.newResponse(api.httpClient().Do(httpReq))
+	httpResp, err := api.httpClient().Do(httpReq)
+	return api.newResponse(ctx, httpResp, err)
 }
diff --git a/internal/ooapi/apis_test.go b/internal/ooapi/apis_test.go
index 6171074..acc52bb 100644
--- a/internal/ooapi/apis_test.go
+++ b/internal/ooapi/apis_test.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:01.254917327 +0200 CEST m=+0.000217025
+// 2021-06-15 10:55:56.308361 +0200 CEST m=+0.000215751
 
 package ooapi
 
@@ -9,7 +9,6 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -18,6 +17,7 @@ import (
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/ooapi/apimodel"
 )
 
@@ -177,7 +177,7 @@ func (h *handleCheckReportID) ServeHTTP(w http.ResponseWriter, r *http.Request)
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -440,7 +440,7 @@ func (h *handleCheckIn) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -685,7 +685,7 @@ func (h *handleLogin) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -912,7 +912,7 @@ func (h *handleMeasurementMeta) ServeHTTP(w http.ResponseWriter, r *http.Request
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -1175,7 +1175,7 @@ func (h *handleRegister) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -1402,7 +1402,7 @@ func (h *handleTestHelpers) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -1671,7 +1671,7 @@ func (h *handlePsiphonConfig) ServeHTTP(w http.ResponseWriter, r *http.Request)
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -1942,7 +1942,7 @@ func (h *handleTorTargets) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -2192,7 +2192,7 @@ func (h *handleURLs) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -2437,7 +2437,7 @@ func (h *handleOpenReport) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -2682,7 +2682,7 @@ func (h *handleSubmitMeasurement) ServeHTTP(w http.ResponseWriter, r *http.Reque
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
diff --git a/internal/ooapi/caching.go b/internal/ooapi/caching.go
index 640cdcc..cf05d5c 100644
--- a/internal/ooapi/caching.go
+++ b/internal/ooapi/caching.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:01.869492095 +0200 CEST m=+0.000168945
+// 2021-06-15 10:55:56.587245 +0200 CEST m=+0.000218959
 
 package ooapi
 
diff --git a/internal/ooapi/caching_test.go b/internal/ooapi/caching_test.go
index 0c6c1c7..e5085d6 100644
--- a/internal/ooapi/caching_test.go
+++ b/internal/ooapi/caching_test.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:02.497717446 +0200 CEST m=+0.000113904
+// 2021-06-15 10:55:56.851681 +0200 CEST m=+0.000186126
 
 package ooapi
 
diff --git a/internal/ooapi/callers.go b/internal/ooapi/callers.go
index 87a9fe8..7a4ae4c 100644
--- a/internal/ooapi/callers.go
+++ b/internal/ooapi/callers.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:03.02266641 +0200 CEST m=+0.000097757
+// 2021-06-15 10:55:57.174427 +0200 CEST m=+0.000217876
 
 package ooapi
 
diff --git a/internal/ooapi/clientcall.go b/internal/ooapi/clientcall.go
index 6e094ea..60dddd6 100644
--- a/internal/ooapi/clientcall.go
+++ b/internal/ooapi/clientcall.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:03.586305848 +0200 CEST m=+0.000123000
+// 2021-06-15 10:55:57.445485 +0200 CEST m=+0.000219751
 
 package ooapi
 
diff --git a/internal/ooapi/clientcall_test.go b/internal/ooapi/clientcall_test.go
index 438b655..fa0210f 100644
--- a/internal/ooapi/clientcall_test.go
+++ b/internal/ooapi/clientcall_test.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:04.198485035 +0200 CEST m=+0.000114145
+// 2021-06-15 10:55:57.708833 +0200 CEST m=+0.000193418
 
 package ooapi
 
@@ -8,7 +8,6 @@ package ooapi
 import (
 	"context"
 	"encoding/json"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -16,6 +15,7 @@ import (
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/kvstore"
 	"github.com/ooni/probe-cli/v3/internal/ooapi/apimodel"
 )
@@ -42,7 +42,7 @@ func (h *handleClientCallCheckReportID) ServeHTTP(w http.ResponseWriter, r *http
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -135,7 +135,7 @@ func (h *handleClientCallCheckIn) ServeHTTP(w http.ResponseWriter, r *http.Reque
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -227,7 +227,7 @@ func (h *handleClientCallMeasurementMeta) ServeHTTP(w http.ResponseWriter, r *ht
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -320,7 +320,7 @@ func (h *handleClientCallTestHelpers) ServeHTTP(w http.ResponseWriter, r *http.R
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -435,7 +435,7 @@ func (h *handleClientCallPsiphonConfig) ServeHTTP(w http.ResponseWriter, r *http
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -550,7 +550,7 @@ func (h *handleClientCallTorTargets) ServeHTTP(w http.ResponseWriter, r *http.Re
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -643,7 +643,7 @@ func (h *handleClientCallURLs) ServeHTTP(w http.ResponseWriter, r *http.Request)
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -736,7 +736,7 @@ func (h *handleClientCallOpenReport) ServeHTTP(w http.ResponseWriter, r *http.Re
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
@@ -828,7 +828,7 @@ func (h *handleClientCallSubmitMeasurement) ServeHTTP(w http.ResponseWriter, r *
 	}
 	h.count++
 	if r.Body != nil {
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := iox.ReadAllContext(r.Context(), r.Body)
 		if err != nil {
 			w.WriteHeader(400)
 			return
diff --git a/internal/ooapi/cloners.go b/internal/ooapi/cloners.go
index e058269..2eced32 100644
--- a/internal/ooapi/cloners.go
+++ b/internal/ooapi/cloners.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:04.793154609 +0200 CEST m=+0.000108739
+// 2021-06-15 10:55:57.987741 +0200 CEST m=+0.000211126
 
 package ooapi
 
diff --git a/internal/ooapi/fake_test.go b/internal/ooapi/fake_test.go
index 9b0b708..9738d6c 100644
--- a/internal/ooapi/fake_test.go
+++ b/internal/ooapi/fake_test.go
@@ -3,9 +3,10 @@ package ooapi
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"time"
+
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 type FakeCodec struct {
@@ -30,7 +31,7 @@ type FakeHTTPClient struct {
 func (c *FakeHTTPClient) Do(req *http.Request) (*http.Response, error) {
 	time.Sleep(10 * time.Microsecond)
 	if req.Body != nil {
-		_, _ = ioutil.ReadAll(req.Body)
+		_, _ = iox.ReadAllContext(req.Context(), req.Body)
 		req.Body.Close()
 	}
 	if c.Err != nil {
diff --git a/internal/ooapi/fakeapi_test.go b/internal/ooapi/fakeapi_test.go
index 12d2e14..7b040e6 100644
--- a/internal/ooapi/fakeapi_test.go
+++ b/internal/ooapi/fakeapi_test.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:05.331414434 +0200 CEST m=+0.000124504
+// 2021-06-15 10:55:58.234786 +0200 CEST m=+0.000218167
 
 package ooapi
 
diff --git a/internal/ooapi/internal/generator/apis.go b/internal/ooapi/internal/generator/apis.go
index 1d15cda..cbaedd9 100644
--- a/internal/ooapi/internal/generator/apis.go
+++ b/internal/ooapi/internal/generator/apis.go
@@ -156,7 +156,8 @@ func (d *Descriptor) genNewAPI(sb *strings.Builder) {
 	fmt.Fprint(sb, "\tif api.UserAgent != \"\" {\n")
 	fmt.Fprint(sb, "\t\thttpReq.Header.Add(\"User-Agent\", api.UserAgent)\n")
 	fmt.Fprint(sb, "\t}\n")
-	fmt.Fprint(sb, "\treturn api.newResponse(api.httpClient().Do(httpReq))\n")
+	fmt.Fprint(sb, "\thttpResp, err := api.httpClient().Do(httpReq)\n")
+	fmt.Fprint(sb, "\treturn api.newResponse(ctx, httpResp, err)\n")
 	fmt.Fprint(sb, "}\n\n")
 }
 
diff --git a/internal/ooapi/internal/generator/apistest.go b/internal/ooapi/internal/generator/apistest.go
index feeb7c8..02dba5b 100644
--- a/internal/ooapi/internal/generator/apistest.go
+++ b/internal/ooapi/internal/generator/apistest.go
@@ -231,7 +231,7 @@ func (d *Descriptor) genTestRoundTrip(sb *strings.Builder) {
 	fmt.Fprint(sb, "\t}\n")
 	fmt.Fprint(sb, "\th.count++\n")
 	fmt.Fprint(sb, "\tif r.Body != nil {\n")
-	fmt.Fprint(sb, "\t\tdata, err := ioutil.ReadAll(r.Body)\n")
+	fmt.Fprint(sb, "\t\tdata, err := iox.ReadAllContext(r.Context(), r.Body)\n")
 	fmt.Fprint(sb, "\t\tif err != nil {\n")
 	fmt.Fprintf(sb, "\t\t\tw.WriteHeader(400)\n")
 	fmt.Fprintf(sb, "\t\t\treturn\n")
@@ -443,7 +443,6 @@ func GenAPIsTestGo(file string) {
 	fmt.Fprint(&sb, "\t\"context\"\n")
 	fmt.Fprint(&sb, "\t\"encoding/json\"\n")
 	fmt.Fprint(&sb, "\t\"errors\"\n")
-	fmt.Fprint(&sb, "\t\"io/ioutil\"\n")
 	fmt.Fprint(&sb, "\t\"net/http/httptest\"\n")
 	fmt.Fprint(&sb, "\t\"net/http\"\n")
 	fmt.Fprint(&sb, "\t\"net/url\"\n")
@@ -452,6 +451,7 @@ func GenAPIsTestGo(file string) {
 	fmt.Fprint(&sb, "\t\"sync\"\n")
 	fmt.Fprint(&sb, "\n")
 	fmt.Fprint(&sb, "\t\"github.com/google/go-cmp/cmp\"\n")
+	fmt.Fprint(&sb, "\t\"github.com/ooni/probe-cli/v3/internal/iox\"\n")
 	fmt.Fprint(&sb, "\t\"github.com/ooni/probe-cli/v3/internal/ooapi/apimodel\"\n")
 	fmt.Fprint(&sb, ")\n")
 	for _, desc := range Descriptors {
diff --git a/internal/ooapi/internal/generator/clientcalltest.go b/internal/ooapi/internal/generator/clientcalltest.go
index 0443d80..01fa47c 100644
--- a/internal/ooapi/internal/generator/clientcalltest.go
+++ b/internal/ooapi/internal/generator/clientcalltest.go
@@ -57,7 +57,7 @@ func (d *Descriptor) genTestClientCallRoundTrip(sb *strings.Builder) {
 	fmt.Fprint(sb, "\t}\n")
 	fmt.Fprint(sb, "\th.count++\n")
 	fmt.Fprint(sb, "\tif r.Body != nil {\n")
-	fmt.Fprint(sb, "\t\tdata, err := ioutil.ReadAll(r.Body)\n")
+	fmt.Fprint(sb, "\t\tdata, err := iox.ReadAllContext(r.Context(), r.Body)\n")
 	fmt.Fprint(sb, "\t\tif err != nil {\n")
 	fmt.Fprintf(sb, "\t\t\tw.WriteHeader(400)\n")
 	fmt.Fprintf(sb, "\t\t\treturn\n")
@@ -161,7 +161,6 @@ func GenClientCallTestGo(file string) {
 	fmt.Fprint(&sb, "import (\n")
 	fmt.Fprint(&sb, "\t\"context\"\n")
 	fmt.Fprint(&sb, "\t\"encoding/json\"\n")
-	fmt.Fprint(&sb, "\t\"io/ioutil\"\n")
 	fmt.Fprint(&sb, "\t\"net/http/httptest\"\n")
 	fmt.Fprint(&sb, "\t\"net/http\"\n")
 	fmt.Fprint(&sb, "\t\"net/url\"\n")
@@ -169,6 +168,7 @@ func GenClientCallTestGo(file string) {
 	fmt.Fprint(&sb, "\t\"sync\"\n")
 	fmt.Fprint(&sb, "\n")
 	fmt.Fprint(&sb, "\t\"github.com/google/go-cmp/cmp\"\n")
+	fmt.Fprint(&sb, "\t\"github.com/ooni/probe-cli/v3/internal/iox\"\n")
 	fmt.Fprint(&sb, "\t\"github.com/ooni/probe-cli/v3/internal/kvstore\"\n")
 	fmt.Fprint(&sb, "\t\"github.com/ooni/probe-cli/v3/internal/ooapi/apimodel\"\n")
 	fmt.Fprint(&sb, ")\n")
diff --git a/internal/ooapi/internal/generator/responses.go b/internal/ooapi/internal/generator/responses.go
index da81013..3a7ad30 100644
--- a/internal/ooapi/internal/generator/responses.go
+++ b/internal/ooapi/internal/generator/responses.go
@@ -9,7 +9,7 @@ import (
 
 func (d *Descriptor) genNewResponse(sb *strings.Builder) {
 	fmt.Fprintf(sb,
-		"func (api *%s) newResponse(resp *http.Response, err error) (%s, error) {\n",
+		"func (api *%s) newResponse(ctx context.Context, resp *http.Response, err error) (%s, error) {\n",
 		d.APIStructName(), d.ResponseTypeName())
 
 	fmt.Fprint(sb, "\tif err != nil {\n")
@@ -23,7 +23,7 @@ func (d *Descriptor) genNewResponse(sb *strings.Builder) {
 	fmt.Fprint(sb, "\t}\n")
 	fmt.Fprint(sb, "\tdefer resp.Body.Close()\n")
 	fmt.Fprint(sb, "\treader := io.LimitReader(resp.Body, 4<<20)\n")
-	fmt.Fprint(sb, "\tdata, err := ioutil.ReadAll(reader)\n")
+	fmt.Fprint(sb, "\tdata, err := iox.ReadAllContext(ctx, reader)\n")
 	fmt.Fprint(sb, "\tif err != nil {\n")
 	fmt.Fprint(sb, "\t\treturn nil, err\n")
 	fmt.Fprint(sb, "\t}\n")
@@ -67,10 +67,11 @@ func GenResponsesGo(file string) {
 	fmt.Fprint(&sb, "package ooapi\n\n")
 	fmt.Fprintf(&sb, "//go:generate go run ./internal/generator -file %s\n\n", file)
 	fmt.Fprint(&sb, "import (\n")
+	fmt.Fprint(&sb, "\t\"context\"\n")
 	fmt.Fprint(&sb, "\t\"io\"\n")
-	fmt.Fprint(&sb, "\t\"io/ioutil\"\n")
 	fmt.Fprint(&sb, "\t\"net/http\"\n")
 	fmt.Fprint(&sb, "\n")
+	fmt.Fprint(&sb, "\t\"github.com/ooni/probe-cli/v3/internal/iox\"\n")
 	fmt.Fprint(&sb, "\t\"github.com/ooni/probe-cli/v3/internal/ooapi/apimodel\"\n")
 	fmt.Fprint(&sb, ")\n\n")
 	for _, desc := range Descriptors {
diff --git a/internal/ooapi/login.go b/internal/ooapi/login.go
index 2c52aca..f629eec 100644
--- a/internal/ooapi/login.go
+++ b/internal/ooapi/login.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:06.213159282 +0200 CEST m=+0.000104135
+// 2021-06-15 10:55:58.487888 +0200 CEST m=+0.000221710
 
 package ooapi
 
diff --git a/internal/ooapi/login_test.go b/internal/ooapi/login_test.go
index 8131618..037a4e7 100644
--- a/internal/ooapi/login_test.go
+++ b/internal/ooapi/login_test.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:06.893164862 +0200 CEST m=+0.000136881
+// 2021-06-15 10:55:58.755431 +0200 CEST m=+0.000217917
 
 package ooapi
 
diff --git a/internal/ooapi/loginhandler_test.go b/internal/ooapi/loginhandler_test.go
index 3ceac37..51242a9 100644
--- a/internal/ooapi/loginhandler_test.go
+++ b/internal/ooapi/loginhandler_test.go
@@ -2,7 +2,6 @@ package ooapi
 
 import (
 	"encoding/json"
-	"io/ioutil"
 	"net/http"
 	"strings"
 	"sync"
@@ -10,6 +9,7 @@ import (
 	"time"
 
 	"github.com/ooni/probe-cli/v3/internal/atomicx"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/ooapi/apimodel"
 )
 
@@ -72,7 +72,7 @@ func (lh *LoginHandler) register(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(400)
 		return
 	}
-	data, err := ioutil.ReadAll(r.Body)
+	data, err := iox.ReadAllContext(r.Context(), r.Body)
 	if err != nil {
 		w.WriteHeader(400)
 		return
@@ -113,7 +113,7 @@ func (lh *LoginHandler) login(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(400)
 		return
 	}
-	data, err := ioutil.ReadAll(r.Body)
+	data, err := iox.ReadAllContext(r.Context(), r.Body)
 	if err != nil {
 		w.WriteHeader(400)
 		return
diff --git a/internal/ooapi/requests.go b/internal/ooapi/requests.go
index 7f23cdb..4e2ff33 100644
--- a/internal/ooapi/requests.go
+++ b/internal/ooapi/requests.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:07.590481334 +0200 CEST m=+0.000085230
+// 2021-06-15 10:55:59.020364 +0200 CEST m=+0.000217085
 
 package ooapi
 
diff --git a/internal/ooapi/responses.go b/internal/ooapi/responses.go
index da6078c..4401eb9 100644
--- a/internal/ooapi/responses.go
+++ b/internal/ooapi/responses.go
@@ -1,19 +1,20 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:08.237841277 +0200 CEST m=+0.000121556
+// 2021-06-15 10:55:59.329509 +0200 CEST m=+0.000220043
 
 package ooapi
 
 //go:generate go run ./internal/generator -file responses.go
 
 import (
+	"context"
 	"io"
-	"io/ioutil"
 	"net/http"
 
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/ooapi/apimodel"
 )
 
-func (api *simpleCheckReportIDAPI) newResponse(resp *http.Response, err error) (*apimodel.CheckReportIDResponse, error) {
+func (api *simpleCheckReportIDAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.CheckReportIDResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -25,7 +26,7 @@ func (api *simpleCheckReportIDAPI) newResponse(resp *http.Response, err error) (
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -36,7 +37,7 @@ func (api *simpleCheckReportIDAPI) newResponse(resp *http.Response, err error) (
 	return out, nil
 }
 
-func (api *simpleCheckInAPI) newResponse(resp *http.Response, err error) (*apimodel.CheckInResponse, error) {
+func (api *simpleCheckInAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.CheckInResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -48,7 +49,7 @@ func (api *simpleCheckInAPI) newResponse(resp *http.Response, err error) (*apimo
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -59,7 +60,7 @@ func (api *simpleCheckInAPI) newResponse(resp *http.Response, err error) (*apimo
 	return out, nil
 }
 
-func (api *simpleLoginAPI) newResponse(resp *http.Response, err error) (*apimodel.LoginResponse, error) {
+func (api *simpleLoginAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.LoginResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -71,7 +72,7 @@ func (api *simpleLoginAPI) newResponse(resp *http.Response, err error) (*apimode
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -82,7 +83,7 @@ func (api *simpleLoginAPI) newResponse(resp *http.Response, err error) (*apimode
 	return out, nil
 }
 
-func (api *simpleMeasurementMetaAPI) newResponse(resp *http.Response, err error) (*apimodel.MeasurementMetaResponse, error) {
+func (api *simpleMeasurementMetaAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.MeasurementMetaResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -94,7 +95,7 @@ func (api *simpleMeasurementMetaAPI) newResponse(resp *http.Response, err error)
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -105,7 +106,7 @@ func (api *simpleMeasurementMetaAPI) newResponse(resp *http.Response, err error)
 	return out, nil
 }
 
-func (api *simpleRegisterAPI) newResponse(resp *http.Response, err error) (*apimodel.RegisterResponse, error) {
+func (api *simpleRegisterAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.RegisterResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -117,7 +118,7 @@ func (api *simpleRegisterAPI) newResponse(resp *http.Response, err error) (*apim
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -128,7 +129,7 @@ func (api *simpleRegisterAPI) newResponse(resp *http.Response, err error) (*apim
 	return out, nil
 }
 
-func (api *simpleTestHelpersAPI) newResponse(resp *http.Response, err error) (apimodel.TestHelpersResponse, error) {
+func (api *simpleTestHelpersAPI) newResponse(ctx context.Context, resp *http.Response, err error) (apimodel.TestHelpersResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -140,7 +141,7 @@ func (api *simpleTestHelpersAPI) newResponse(resp *http.Response, err error) (ap
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -154,7 +155,7 @@ func (api *simpleTestHelpersAPI) newResponse(resp *http.Response, err error) (ap
 	return out, nil
 }
 
-func (api *simplePsiphonConfigAPI) newResponse(resp *http.Response, err error) (apimodel.PsiphonConfigResponse, error) {
+func (api *simplePsiphonConfigAPI) newResponse(ctx context.Context, resp *http.Response, err error) (apimodel.PsiphonConfigResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -166,7 +167,7 @@ func (api *simplePsiphonConfigAPI) newResponse(resp *http.Response, err error) (
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -180,7 +181,7 @@ func (api *simplePsiphonConfigAPI) newResponse(resp *http.Response, err error) (
 	return out, nil
 }
 
-func (api *simpleTorTargetsAPI) newResponse(resp *http.Response, err error) (apimodel.TorTargetsResponse, error) {
+func (api *simpleTorTargetsAPI) newResponse(ctx context.Context, resp *http.Response, err error) (apimodel.TorTargetsResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -192,7 +193,7 @@ func (api *simpleTorTargetsAPI) newResponse(resp *http.Response, err error) (api
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -206,7 +207,7 @@ func (api *simpleTorTargetsAPI) newResponse(resp *http.Response, err error) (api
 	return out, nil
 }
 
-func (api *simpleURLsAPI) newResponse(resp *http.Response, err error) (*apimodel.URLsResponse, error) {
+func (api *simpleURLsAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.URLsResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -218,7 +219,7 @@ func (api *simpleURLsAPI) newResponse(resp *http.Response, err error) (*apimodel
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -229,7 +230,7 @@ func (api *simpleURLsAPI) newResponse(resp *http.Response, err error) (*apimodel
 	return out, nil
 }
 
-func (api *simpleOpenReportAPI) newResponse(resp *http.Response, err error) (*apimodel.OpenReportResponse, error) {
+func (api *simpleOpenReportAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.OpenReportResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -241,7 +242,7 @@ func (api *simpleOpenReportAPI) newResponse(resp *http.Response, err error) (*ap
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
@@ -252,7 +253,7 @@ func (api *simpleOpenReportAPI) newResponse(resp *http.Response, err error) (*ap
 	return out, nil
 }
 
-func (api *simpleSubmitMeasurementAPI) newResponse(resp *http.Response, err error) (*apimodel.SubmitMeasurementResponse, error) {
+func (api *simpleSubmitMeasurementAPI) newResponse(ctx context.Context, resp *http.Response, err error) (*apimodel.SubmitMeasurementResponse, error) {
 	if err != nil {
 		return nil, err
 	}
@@ -264,7 +265,7 @@ func (api *simpleSubmitMeasurementAPI) newResponse(resp *http.Response, err erro
 	}
 	defer resp.Body.Close()
 	reader := io.LimitReader(resp.Body, 4<<20)
-	data, err := ioutil.ReadAll(reader)
+	data, err := iox.ReadAllContext(ctx, reader)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/ooapi/swagger_test.go b/internal/ooapi/swagger_test.go
index c44a93e..5539e5e 100644
--- a/internal/ooapi/swagger_test.go
+++ b/internal/ooapi/swagger_test.go
@@ -1,5 +1,5 @@
 // Code generated by go generate; DO NOT EDIT.
-// 2021-05-12 09:15:08.888123159 +0200 CEST m=+0.000883704
+// 2021-06-15 10:55:59.636856 +0200 CEST m=+0.000624459
 
 package ooapi
 
@@ -9,7 +9,7 @@ const swagger = `{
     "swagger": "2.0",
     "info": {
         "title": "OONI API specification",
-        "version": "0.20210512.5071508"
+        "version": "0.20210615.6085559"
     },
     "host": "api.ooni.io",
     "basePath": "/",
diff --git a/internal/ooapi/swaggerdiff_test.go b/internal/ooapi/swaggerdiff_test.go
index d805223..31ea27c 100644
--- a/internal/ooapi/swaggerdiff_test.go
+++ b/internal/ooapi/swaggerdiff_test.go
@@ -1,9 +1,9 @@
 package ooapi
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"sort"
@@ -13,6 +13,7 @@ import (
 	"github.com/hexops/gotextdiff"
 	"github.com/hexops/gotextdiff/myers"
 	"github.com/hexops/gotextdiff/span"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 	"github.com/ooni/probe-cli/v3/internal/ooapi/internal/openapi"
 )
 
@@ -36,7 +37,7 @@ func getServerModel(serverURL string) *openapi.Swagger {
 		log.Fatal(err)
 	}
 	defer resp.Body.Close()
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/internal/ptx/ptx_test.go b/internal/ptx/ptx_test.go
index c7ef744..64f5bc6 100644
--- a/internal/ptx/ptx_test.go
+++ b/internal/ptx/ptx_test.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
@@ -15,6 +14,7 @@ import (
 	"github.com/apex/log"
 	"github.com/ooni/probe-cli/v3/internal/atomicx"
 	"github.com/ooni/probe-cli/v3/internal/engine/netx/mockablex"
+	"github.com/ooni/probe-cli/v3/internal/iox"
 )
 
 func TestListenerLoggerWorks(t *testing.T) {
@@ -57,7 +57,7 @@ func TestListenerWorksWithFakeDialer(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	data, err := ioutil.ReadAll(resp.Body)
+	data, err := iox.ReadAllContext(context.Background(), resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}