Content-Addressed Storage Needs More Than a Hash Key
Use content digests as chunk identifiers for dedupe and integrity with algorithm versioning, atomic writes, reference tracking, garbage collection, and untrusted-data revalidation.
uCopy Technical Blog
Clear explanations for connections that work in real life · Page 3
Practical uCopy guides to WebRTC, P2P file transfer, STUN and TURN, LAN discovery, resumable transfers, screen sharing, privacy, and security.
WebRTCP2P transferSTUN / TURNPrivacy & security
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Content-Defined Chunking: Reusing Data After a File Changes
Compare fixed chunks with rolling-hash content-defined chunks across inserted bytes, deduplication gain, CPU cost, digest indexes, and browser implementation tradeoffs.
CSP for Real-Time Web Apps Without Breaking WebRTC or Workers
Build CSP with nonces, strict-dynamic, connect-src, worker-src, and report-only rollout across signaling, analytics, Blob workers, and screen-sharing pages.
Hardening coturn Against Anonymous Relay and Unsafe Defaults
Configure long-term credentials, realm, fingerprint, stale nonce, peer restrictions, listener interfaces, and admin exposure to prevent open relay and internal access.
A Cross-Device Clipboard That Respects Permissions and Privacy
Design a clipboard handoff between computer and phone with browser permissions, receipts, separate queues, offline behavior, conflict handling, history cleanup, and safe analytics.
Stable Cursor Pagination Without Duplicates or Gaps During Changes
Paginate activity with immutable sort keys, unique tie-breakers, signed cursors, direction semantics, and clear behavior under equal timestamps, deletion, filters, and snapshots.
Propagating Deletion Across Databases, Caches, and Objects
Use deletion workflows, tombstones, idempotent consumers, and completion evidence across caches, search, objects, analytics, and downstream exports.
Reliable, Ordered, or Partially Reliable DataChannels by Message Type
Compare ordered delivery, maxRetransmits, and maxPacketLifeTime for chat, file control, bulk chunks, cursors, and transient real-time state.
Design Tokens for Dark Mode Instead of Color Inversion
Build themes from semantic colors, layered surfaces, borders, states, shadows, and system preference while handling contrast, charts, third-party UI, and theme flash.
Testing Timeouts and Backoff with a Deterministic Virtual Clock
Inject timers, current time, and scheduling queues into protocol code so heartbeats, leases, retry, deadlines, and resume can be tested by virtual advancement.
Device Identity Keys from Generation Through Revocation
Generate non-exportable browser keys, establish identity from signed public keys, and design storage, recovery, rotation, loss handling, and revocation propagation.
Device Trust Revocation Across UI, Sessions, and Existing Tokens
Design confirmation, immediate disconnect, capability-token invalidation, cross-device propagation, offline stale-device handling, and repair so users truly withdraw access.
Differential Privacy for Product Metrics and When Not to Use It
Choose counting queries, clipping, privacy budgets, and noise for high-level usage and network distribution while understanding small samples, repeated release, and debugging tradeoffs.
Transferring a Folder: Manifests, Path Safety, and Partial Recovery
Define a stable directory manifest covering empty folders, symlinks, duplicate names, path traversal, cross-platform characters, total-size approval, and per-file resume.
DNS Failover for Real-Time Services Beyond a Short TTL
Combine multiple addresses, health withdrawal, client re-resolution, regional fallback, and session recovery while accounting for caches, negative caching, and long-lived connections.
How NXDOMAIN, Timeout, and DNS Caches Break Real-Time Connections
Separate authoritative errors, resolver timeout, SERVFAIL, negative caching, DoH, and split-horizon behavior for signaling and TURN diagnostics.
Editorial Quality Gates Beyond Word Count and Keyword Density
Maintain a large technical library through topic uniqueness, factual density, actionable decisions, failure paths, verification, source freshness, and duplication checks.
Designing an Empty Local-Discovery State That Helps Users Succeed
Distinguish scanning, missing permission, unsupported network, no peer, and discovery failure with diagnostics, code-based fallback, and privacy explanation.
Controlling Main-Thread Long Tasks in Real-Time Web Apps
Use task slicing, workers, scheduling priority, and long-task telemetry so hashing, rendering, and compression cannot block heartbeats, signaling, or cancel actions.
Testing Exactly-Once Notification Effects over Duplicate Delivery
Use stable event IDs, atomic claims, and notification tags so at-least-once messages, Service Worker restarts, and multiple tabs yield one user-visible alert.
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