What to Consider When Building a Desktop Recorder for Windows and macOS
A desktop meeting recorder runs directly on the user's computer and captures the meeting's audio and video. Here's what to consider when building one for both Windows and macOS.
A desktop meeting recorder is a popular way to capture meetings without adding a bot to the call. It runs directly on the user’s computer and captures the meeting’s audio and video.
How difficult it is to build one depends heavily on the approach you take.
With something like a desktop recording SDK, you can probably get a basic prototype running on both macOS and Windows in less than an hour because most of the recording infrastructure is already handled for you. If you build directly with native or cross-platform APIs, you need separate capture implementations for Windows and macOS, along with fallback paths for different OS versions.
The path you choose determines whether building a desktop recorder is a quick integration or a major engineering project. Let’s walk through some of the parts that tend to get tricky.
1. System-audio capture works differently on Windows and macOS
Windows and macOS take very different approaches to capturing audio playing through the computer.
On Windows, WASAPI loopback capture can record the complete audio mix playing through an output device. macOS uses a different set of tools, including ScreenCaptureKit and Core Audio process taps. The right capture method depends on the macOS version the user is running.
The version gap is significant: ScreenCaptureKit was introduced in macOS 12.3, while Core Audio process taps require macOS 14.2 or later. Users on unsupported versions need an alternative capture method.
A production recorder therefore needs to detect the user’s platform and operating-system version before selecting the appropriate capture path. This means maintaining separate implementations for Windows and macOS, along with fallback methods for older macOS versions.
2. Separating system and microphone audio requires different capture paths
On both Windows and macOS, you will usually want to keep the local microphone separate from the outgoing meeting audio. Keeping them separate lets you adjust each track independently, use the meeting audio as a reference for echo cancellation, and more reliably distinguish the local user from remote participants in the transcript.
The two operating systems provide these tracks in different ways. On Windows, you might combine microphone capture with WASAPI loopback or process-specific audio capture. On macOS, the approach depends on the OS version and may involve ScreenCaptureKit, Core Audio process taps, AVFoundation, or a combination of them.
Separate tracks also need to stay synchronized. When they come from different devices or capture pipelines, they may not share the same clock. Apple’s own guidance says that audio devices without hardware synchronization require drift correction, or resampling, to compensate for timing differences. Without similar correction in your recorder, the microphone and meeting audio can gradually move out of alignment during a long call.
3. Audio-device switching needs to work on both Windows and macOS
Users changing audio devices mid-meeting is easy to overlook during local testing, since you are probably using the same microphone for every recording. But real users are less predictable: their AirPods can run out of battery or switch from headphones to speakers halfway through a meeting.
Windows and macOS expose device changes through different APIs, so each platform needs its own detection and recovery logic. Otherwise, the recorder may miss everything said after the device switch. It needs to detect the new device, move capture to it, and continue recording with as little interruption as possible.
4. Windows and macOS have different permissions flow
Permissions are another area where the two platforms behave differently.
On macOS, your recorder may need access to the microphone, screen and system audio, and accessibility features, depending on its functionality. These capabilities are managed separately, so approving one does not automatically grant access to the others. Windows is generally less prompt-heavy for traditional desktop apps.
The possible permission states add up quickly. If your implementation depends on four independently controlled permissions, there are up to 16 combinations of approvals and denials. Differences between OS versions add another layer, since the available permissions and the way users grant them can change.
Your app needs to check the current permission state on each operating system, and also anticipate when someone denies access or changes a permission later. For example, it might record audio without video when screen access is denied or require the user to start recording manually when accessibility access is unavailable.
5. Meeting window detection varies across operating systems and apps
Finding the right meeting window sounds straightforward until you look at a real user’s desktop. They might have several Chrome windows open, or have their meeting window in a picture-in-picture format.
The challenge comes from the fact that the underlying capture APIs identify screens, applications, and windows, not meetings. For example, Apple’s ScreenCaptureKit can capture a specific window, but it cannot tell whether that window contains a meeting. If the user switches from Google Meet to another tab in the same browser window, ScreenCaptureKit will continue capturing the window and may record the wrong content unless you add meeting-aware detection logic.
A desktop meeting recorder therefore needs meeting-aware logic that can identify the meeting application, determine which windows belong to it, and update the capture target when the meeting moves. That logic needs separate testing on Windows and macOS because each platform exposes different window identifiers and metadata.
6. Reducing strain on user’s device across macOS and Windows
Desktop recording can use more resources than you might expect. Your app may be capturing and encoding several media tracks, writing them to disk, and uploading them while Zoom or Teams competes for the same CPU, GPU, memory, and network capacity.
Performance varies across Intel Macs, Apple silicon, and Windows hardware. Your recorder may need to adjust its resolution, frame rate, bitrate, and buffering based on the device. It should also use hardware encoding when available and fall back to lighter settings when necessary. Ideally, users should barely notice that it is running. This is why you may need to use different hardware encoders or performance settings on each platform.
7. Recordings need to survive interruptions on all operating systems
During a long meeting, something will eventually go wrong. The app may crash, the laptop may sleep, or the internet may drop. Windows and macOS handle lifecycle and recovery events differently, so each platform needs its own logic.
In production, interruptions are almost inevitable. The goal is not to prevent every failure, but to design the recording system so each one results in as little lost media as possible.
8. Supporting both macOS and Windows makes the testing scope expand
Supporting Windows and macOS does not create just two configurations. Each operating system has multiple versions, hardware types, capture APIs, permission states, browsers, meeting apps, and audio devices.
Before long, the combination of things you need to test looks something like:
Operating system x version × meeting platform × browser or native app × hardware × audio device
Testing needs to cover the combinations your users actually have, including older hardware, denied permissions, device changes, unstable networks, and long meetings. Supporting both Windows and macOS means continuing that work as the operating systems, browsers, and meeting applications change.
How to build a desktop recorder for Windows and macOS in under an hour
The challenges above are only some of what goes into getting a desktop meeting recorder ready for production. If you do not want to build and maintain all of that infrastructure yourself, Recall.ai’s Desktop Recording SDK can help you get there much faster.
We got a prototype running quickly with audio and video recordings and speaker-labeled transcripts. It was easy to see how much engineering work the Desktop Recording SDK could save and fit into an existing product.
It also works across Windows and macOS, so teams do not have to manage all the platform-specific capture paths described above. They can spend more time building useful features with meeting data and less time maintaining the recording infrastructure underneath them.