diff --git a/src/API.jl b/src/API.jl
index 17e6c3b45f..be226e53a4 100644
--- a/src/API.jl
+++ b/src/API.jl
@@ -1273,15 +1273,15 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
         end
     end
 
-    stderr_outputs = Dict{Base.PkgId,String}()
+    std_outputs = Dict{Base.PkgId,String}()
     taskwaiting = Set{Base.PkgId}()
     pkgspidlocked = Dict{Base.PkgId,String}()
 
-    function monitor_stderr(pkg, iob)
+    function monitor_std(pkg, pipe)
         try
-            while isopen(iob)
-                str = readline(iob)
-                stderr_outputs[pkg] = get(stderr_outputs, pkg, "") * str * "\n"
+            while !eof(pipe)
+                str = readline(pipe, keep=true)
+                std_outputs[pkg] = string(get(std_outputs, pkg, ""), str)
                 if !in(pkg, taskwaiting) && occursin("waiting for IO to finish", str)
                     !fancyprint && lock(print_lock) do
                         println(io, pkg.name, color_string(" Waiting for background task / IO / timer.", Base.warn_color()))
@@ -1290,7 +1290,7 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
                 end
                 if !fancyprint && in(pkg, taskwaiting)
                     lock(print_lock) do
-                        println(io, str)
+                        print(io, str)
                     end
                 end
             end
@@ -1428,8 +1428,8 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
                     is_direct_dep = pkg in direct_deps
 
                     # stderr monitoring
-                    iob = Base.BufferStream()
-                    t_monitor = @async monitor_stderr(pkg, iob)
+                    std_pipe = Base.link_pipe!(Pipe(); reader_supports_async=true, writer_supports_async=true)
+                    t_monitor = @async monitor_std(pkg, std_pipe)
 
                     _name = haskey(exts, pkg) ? string(exts[pkg], " → ", pkg.name) : pkg.name
                     name = is_direct_dep ? _name : string(color_string(_name, :light_black))
@@ -1449,8 +1449,8 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
                         # a functionally identical package cache (except for preferences, which may differ)
                         t = @elapsed ret = maybe_cachefile_lock(io, print_lock, fancyprint, pkg, pkgspidlocked) do
                             Logging.with_logger(Logging.NullLogger()) do
-                                # capture stderr, send stdout to devnull, don't skip loaded modules
-                                Base.compilecache(pkg, sourcepath, iob, devnull, false)
+                                # The false here means we ignore loaded modules, so precompile for a fresh session
+                                Base.compilecache(pkg, sourcepath, std_pipe, std_pipe, false)
                             end
                         end
                         t_str = timing ? string(lpad(round(t * 1e3, digits = 1), 9), " ms") : ""
@@ -1469,11 +1469,11 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
                         end
                         loaded && (n_loaded += 1)
                     catch err
-                        close(iob)
+                        close(std_pipe.in) # close pipe to end the std output monitor
                         wait(t_monitor)
                         if err isa ErrorException || (err isa ArgumentError && startswith(err.msg, "Invalid header in cache file"))
-                            failed_deps[pkg] = (strict || is_direct_dep) ? string(sprint(showerror, err), "\n", get(stderr_outputs, pkg, "")) : ""
-                            delete!(stderr_outputs, pkg) # so it's not shown as warnings, given error report
+                            failed_deps[pkg] = (strict || is_direct_dep) ? string(sprint(showerror, err), "\n", strip(get(std_outputs, pkg, ""))) : ""
+                            delete!(std_outputs, pkg) # so it's not shown as warnings, given error report
                             !fancyprint && lock(print_lock) do
                                 println(io, timing ? " "^9 : "", color_string("  ✗ ", Base.error_color()), name)
                             end
@@ -1483,6 +1483,8 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
                             rethrow()
                         end
                     finally
+                        isopen(std_pipe.in) && close(std_pipe.in) # close pipe to end the std output monitor
+                        wait(t_monitor)
                         Base.release(parallel_limiter)
                     end
                 else
@@ -1515,7 +1517,7 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
     quick_exit = !all(istaskdone, tasks) || interrupted # if some not finished internal error is likely
     seconds_elapsed = round(Int, (time_ns() - time_start) / 1e9)
     ndeps = count(values(was_recompiled))
-    if ndeps > 0 || !isempty(failed_deps) || (quick_exit && !isempty(stderr_outputs))
+    if ndeps > 0 || !isempty(failed_deps) || (quick_exit && !isempty(std_outputs))
         str = sprint() do iostr
             if !quick_exit
                 plural = ndeps == 1 ? "y" : "ies"
@@ -1545,12 +1547,12 @@ function precompile(ctx::Context, pkgs::Vector{PackageSpec}; internal_call::Bool
             end
             # show any stderr output, even if Pkg.precompile has been interrupted (quick_exit=true), given user may be
             # interrupting a hanging precompile job with stderr output. julia#48371
-            filter!(kv -> !isempty(strip(last(kv))), stderr_outputs) # remove empty output
-            if !isempty(stderr_outputs)
-                plural1 = length(stderr_outputs) == 1 ? "y" : "ies"
-                plural2 = length(stderr_outputs) == 1 ? "" : "s"
-                print(iostr, "\n  ", color_string("$(length(stderr_outputs))", Base.warn_color()), " dependenc$(plural1) had output during precompilation:")
-                for (pkgid, err) in stderr_outputs
+            filter!(kv -> !isempty(strip(last(kv))), std_outputs) # remove empty output
+            if !isempty(std_outputs)
+                plural1 = length(std_outputs) == 1 ? "y" : "ies"
+                plural2 = length(std_outputs) == 1 ? "" : "s"
+                print(iostr, "\n  ", color_string("$(length(std_outputs))", Base.warn_color()), " dependenc$(plural1) had output during precompilation:")
+                for (pkgid, err) in std_outputs
                     err = join(split(strip(err), "\n"), color_string("\n│  ", Base.warn_color()))
                     print(iostr, color_string("\n┌ ", Base.warn_color()), pkgid, color_string("\n│  ", Base.warn_color()), err, color_string("\n└  ", Base.warn_color()))
                 end